[0001] This invention relates generally to the display of images, and more particularly
to apparatus for displaying images, and the control of such apparatus.
[0002] An example of the image displays known in the art is given by GB-A-1 226 343, which
also describes an apparatus for image and time duration preselection, complete with
a circuit diagram.
[0003] In accordance with the present invention there is provided a control apparatus for
use with image display means which, in use, sequentially displays images of a selected
group from a plurality of groups of images, said control apparatus comprising processing
means responsive to first control signals to cause said image display means to display
a next image of said selected group of images, and responsive to second control signals
to cause a succeeding group of images to become said selected group, wherein said
second control signals are generated by timer means at predetermined times of the
day.
[0004] In accordance with the present invention there is also provided an image display
apparatus comprising image display means, and control means for controlling said image
display means, said image display means, in use, sequentially displaying images of
a selected group from a plurality of groups of images, said control means comprising
processing means responsive to a first control signal to cause said image display
means to display a next image of said selected group of images, and responsive to
a second control signal to cause a succeeding group of images to become said selected
group, wherein said second control signals are generated by timer means at predetermined
times of the day.
[0005] Preferably said sequence or group of images comprises a number of images joined to
form a length of images coiled, in use, in overlapping fashion upon at least one of
first and second spools. Preferably said groups of images are joined sequentially
to form a length of images such that the last image of one group of images is joined
to the first image of the next group.
[0006] Preferably, when said image display means displays the next image of said sequence
or groups of images, said second spool is rotated so as to coil a portion of said
length of images upon said second spool.
[0007] The image display means may comprise:
motion means for effecting movement of the images into a display area in which
one of said images is displayed, said motion means including at least one electric
motor, and the control means may control said at least one motor to effect said movement
in response to the control signals and motion signals from said at least one motor.
Said motion signals may comprise back emf signals or pulse counting signals, which
indicate movement of said images.
[0008] In a preferred embodiment of the invention the images are contained on a length of
display material which, in use, is coiled upon at least one of first and second cylindrical
spools having generally parallel axes, such that one of the first and second spools
may be rotationally driven to wind a portion of the display material upon the spool
so as to move said image into a display area of the apparatus located between the
two spools. The images contained on the display material may be displayed sequentially,
one by one, whilst the display material is being wound upon the second spool, and
subsequently rewound upon the first spool for the images to again be displayed. The
display material containing a particular sequencies of images may thus be unwound
and rewound upon the first and second spools continuously over the whole or a portion
of the day.
[0009] Preferred embodiments of the present invention will hereinafter be described, by
way of example only, with reference to the accompanying drawings, wherein:
Figure 1 is a block diagram of a preferred display apparatus according to the present
invention;
Figure 2 shows scrolling apparatus of the image display means of a first embodiment;
Figure 3 shows control means of the first embodiment;
Figure 4 is a flow chart of the operation of the control means of Figure 3;
Figure 5 is a modified operational flow chart of the control means of Figure 3;
Figure 6 shows a cut away plan view of the image display apparatus of the first embodiment;
Figure 7 shows a cross-sectional view of the image display apparatus through Section
A-A of Figure 6;
Figure 8 is a truth table for the control means of the scrolling apparatus of the
first embodiment;
Figure 9 shows scrolling apparatus of the image display means of a second embodiment;
Figure 10 shows a cross-sectional view of the image display apparatus in accordance
with the second embodiment;
Figure 11 shows a side view of a tractor feed device for use in the second embodiment;
Figure 12 shows an end view of the tractor feed device of Figure 11;
Figure 13 shows an example of a length of the image display medium, in accordance
with the second embodiment;
Figure 14 is a schematic diagram of the image display apparatus of the second embodiment;
Figure 15 is a schematic diagram of the sound reproduction means of the second embodiment;
Figure 16 shows an example of an internal control panel of the second embodiment;
Figure 17 shows an auxiliary internal control panel of the second embodiment;
Figure 18 shows a main operational flow chart of the control means of the second embodiment
of the present invention;
Figure 19 shows a flow chart for detection of a jammed condition of the scrolling
apparatus;
Figure 20 shows a flow chart of an image group selection routine.
Figure 21 shows a coiled length of display material;
Figure 22 shows a scrolling apparatus;
Figure 23 shows a display material formed from sectional lengths;
Figure 24 shows a cutaway section of the display material of Figure 23, whilst coiled
on a spool;
Figure 25 is a plan view of a tool useful for aligning adjacent sections of display
material prior to interconnection thereof;
Figure 26 is a cross-sectional view of the tool of Figure 25, through 6-6;
Figure 27 is a plan view showing a join between adjacent sectional lengths of display
material;
Figure 28 is a plan view of a tool useful for aligning adjacent sections of display
material prior to interconnection thereof in the fashion showin in Figure 27;
Figure 29 shows a block diagram of image display apparatus according to a third embodiment;
Figure 30 is a programming flowchart for use in the third embodiment; and
Figure 31 is a flowchart of operation of a vicinity movement detector of the third
embodiment.
[0010] The preferred embodiments of the present invention relate to display apparatus useful
in such applications as advertising. The apparatus is relatively inexpensive and simple
in construction, in comparison with alternatives such as video displays. Figure 1
shows a block diagram of the display apparatus 2 comprising visual display means 8,
control means 4 and sound reproduction means 6. Both the visual display means 8 and
the sound reproduction means 6 are operatively connected to the control means 4 such
that the control means is able to control the visual display means and the sound reproduction
means in accordance with a predetermined procedure. In use, the sound reproduction
means 6 provides control signals to the control means 4 which are decoded by the control
means to control the visual display means 8.
[0011] The sound reproduction means 6 may be any common sound reproducing device such as
audio tape or cassette plav back apparatus or may be a digital voice recorder/playback
device. The first embodiment utilises magnetic audio cassette tape apparatus having
a magnetic audio tape which may be formed in a continuous loop. A second embodiment
utilises a digital audio recording and playback device, in use storing and retrieving
sounds digitally in semiconductor memory.
[0012] The image display apparatus 2, as described hereinafter, may comprise a free standing
structure or alternatively may be incorporated in a vending machine, such as a cigarette,
food or drink vending machine. The free standing structure may include a visual display
which is, for example, one and a half metres high and 500 cm wide for enhanced visual
impact. For a display apparatus incorporated in a vending machine, the size of the
display would be ordinarily chosen so as to be of similar dimensions to a static display
which normally exists in such machines. Alternatively, the apparatus may be installed
within a wall of a room such that the visual display faces the interior of the room
in a space which might ordinarily be occupied by an advertising poster or the likes.
The apparatus may, for example, find application in passenger areas of airport buildings,
and could be utilised to identify particular airlines at airport gate areas where
a plurality of airlines use a single gate during different times of the day.
[0013] Figure 2 shows scrolling apparatus 10 of the visual display means 8 of the first
embodiment. The scrolling apparatus 10 comprises upper and lower cylindrical spools
16, 18 upon which are wound a flexible elongate image display medium 24. The spools
16, 18 are arranged in a coplanar parallel orientation, and spaced sufficiently to
allow an image 23 to fit therebetween. The image display medium 24 is formed by piecing
together end-to-end, in sequence, a number of images 23 to be displayed by the display
apparatus. Each image 23 in the sequence may be a transparency tnough which light
is shone to display the image, or may be in the form of a poster. The images are laminated
with transparent plastic to provide protection and stability whilst maintaining flexibility,
and sequentially joined by means of flexible adhesive tape. The edge of one end of
the image display medium 24 is joined to the upper spool 16, and the other end joined
to the lower spool 18. At any one time most of the image display medium 24 is wound
upon one or both of the upper and lower spools 16, 18 in such a way that, in use,
a ponion of the image display medium 24 approximately the size of one image 23 is
held between the two spools at any particular time. The upper spool 16 is rotatably
supported at one end by upper bearing shaft 20, which engages with an upper bearing
carrier 19 (Figure 6), and at the other end is coupled to the rotatable shaft of upper
drive motor 12. Similarly, the lower spool 18 is rotatably supported at one end by
lower bearing shaft 22 and bearing carrier 21, and at the other end coupled to lower
drive motor 14.
[0014] Figures 6 and 7 show the mechanical arrangement of the image display means 8 of the
first embodiment. The upper and lower bearing shafts 20, 22 of the upper and lower
spools rotatably engage with the upper and lower bearing carriers 19, 21 which are
affixed to a chassis 138. The upper and lower drive motors 12, 14 are also affixed
to the chassis 138 such that when the upper drive motor is energised the upper spool
is rotated, and when the lower drive motor is energised the lower spool rotates. The
chassis 138 also supports cylindrical guide bars 144 (not shown in Figure 6), two
guide bars adjacent to each of the upper and lower spools, with each of the guide
bars having its axis parallel to the spools 16, 18. The image display medium 24 is
guided over a desired path from one of the upper and lower spools 16, 18 over two
guide bars 144 to a flat perspex light diffuser 146 (shown in Figure 7) located between
the two spools. The image display medium 24 passes over the surface of the diffuser
146 and over the guide bars to the spool at the other end of the chassis 138. The
apparatus is contained within a box enclosure 136 and cover 148 having a transparent
portion in a position corresponding to that of the diffuser 146. The size of the diffuser
146 and the transparent portion of the cover 148 correspond approximately to the size
of the image 23 to be displayed by the apparatus. The chassis 138 containing the scrolling
apparatus 10 is secured to a rear interior surface of the box enclosure 136 by means
of securing bolts 140. The visual display means also includes fluorescent lights 142
mounted on the rear interior surface of the box enclosure 136 to shine light through
the diffuser 146, the image 23 and the transparent portion of the cover 148 to thereby
display the image 23 currently adjacent the diffuser 146.
[0015] Each of the upper and lower bearing shafts 20, 22 may also be provided with a crank
socket 11 in one end thereof. As shown in Figure 7, the sockets 11 are provided at
the axial center of each bearing shaft 20, 22 in the end thereof which is distal to
that driven by motors 12, 14 respectively. The socket 11 may alternatively be provided
in a gear shaft which is coaxial with and geared to the bearing shaft 20, 22 or spool
16, 18. The sockets 11 are shaped so as to allow a co-operating complimentary crank
handle shaft (not shown) to be inserted therein, such that the crank handle may be
rotated manually to effect rotation of the bearing shaft 20, 22. Such a feature is
useful in the event of a power failure to the image display apparatus, or in the event
of a failure of one of the motors 12, 14 or the controlling circuitry as it enables
some degree of manual control over positioning of the images in the apparatus. To
facilitate easier use of this feature an aperture may be provided in the bos enclosure
136 adjacent each socket 11, to enable a crank handle shaft to be inserted therein
to engage the socket 11.
[0016] Each image 23 is also provided with a stop tab 13 (Figure 2) which cooperates with
an optical sensor 15 (Figure 6, 7) to provide an indication of the correct positioning
of the image 23. A stop tab 13 is positioned in one corner of each image 23 of the
image display medium 24, and the optical sensor 15 is located within the box enclosure
136 such that its sensing surface is adjacent the surface of the image display medium
24 wound on the lower spool 18. The stop tabs are positioned so that, when an image
23 is correctly aligned on the surface of the diffuse; 146, a stop tab 13 is immediately
adjacent the sensing surface of the optical sensor 15.
[0017] Figure 3 is a block diagram of the control system of the first embodiment. The operation
of the control system is coordinated by a control circuit 100 which receives inputs
76, 78, 80, 82, 84, 86 and 88 and provides outputs 90, 92, 94 and 96. The control
circuit 100 may comprise a fixed logic array or a micro controller/microprocessor
type device, however, in the first embodiment the control circuit 100 comprises an
electronically programmable logic device (EPLD).
[0018] Control system 31 receives left and right audio inputs 30, 32 which are summed and
input to an audio buffer amplifier 34. The output of amplifier 34 is fed to a dual
tone multi-frequency (DTMF) decoder 36 which provides four DTMF decoder inputs 76
to the control circuit 100. Control system 31 also receives an input 40 from the optical
sensor 15 which is fed to stop tab sensor 42 and then to buffer amplifier 44. The
output from amplifier 44 provides the stop tab sensor input 80 to control circuit
100.
[0019] A primary function of control system 31 is to synchronise the sequential display
of images on the visual display means 8 with pre-recorded portions of sound reproduced
by the sound reproduction means 6. The synchronisation is effected by means of control
signals which are also reproduced by the sound reproduction means 6. Hence, it is
possible to display an image with the visual display means 8 whilst playing corresponding
pre-recorded sounds such as music or speech relating to the image, and synchronise
the display of the next image in the sequence with the corresponding portion of pre-recorded
sound.
[0020] The control signals utilised in the first embodiment are in the form of DTMF signals,
commonly used in telephone signalling systems. The DTMF signals, which are pre-recorded
on one or both of the left and right audio channels of the sound reproduction means,
are decoded by the DTMF decoder 36 which provides a four bit digital code 76 to the
control circuit 100. Different DTMF codes from the sound reproduction means 6 may
correspond to instructions such as advance to the next image, rewind to the beginning
of the image sequence, return to the previous image in the sequence, etc.
[0021] Control circuit 100 provides three outputs 92, 94, 96 to control the visual display
means 8. Motor drive output 96 is fed to motor drive amplifier 58 and from there to
input terminals of upper and lower relays 66 and 68. Upper motor select output 94
is fed through upper motor drive amplifier 60 to control the switching of upper relay
66. When the upper motor select output 94 is logical 1 the upper relay 66 is switched
such that the output from the motor drive amplifier 58 is connected to upper motor
input 70. When the upper motor select output 94 is not energised upper relay 66 is
switched such that upper motor input 70 is not energised but is electrically connected
to motor sensor 48 via terminal 71. Lower motor select output 92 controls the lower
relay 68 in similar fashion so that, when output 92 is at logic 1 motor drive amplifier
output 58 is connected to lower motor input 72, and when the output 92 is at logic
0 the lower motor input 72 is connected to the motor sensor 48.
[0022] During normal operation of the scrolling apparatus 10 three functions are ordinarily
utilised: scroll up, scroll down, and hold. The scroll up function is effected by
energising upper drive motor 12 whilst leaving lower drive motor 14 disconnected.
Figure 8 shows the logic states of outputs 92, 94 and 96, and the relative voltages
at upper and lower motor inputs 70 and 72. As is apparent from Figure 8, when logic
1 is asserted at motor drive output 96 a relative high voltage appears at the output
of the motor drive amplifier 58. When logical 0 is asserted at the motor drive output
96 the voltage which appears at the output of the motor drive amplifier 58 is a relative
low voltage. Thus, to move the image display medium 24 upwards in the scrolling apparatus
the scroll up function is selected by asserting logical 1 at outputs 94 and 96 and
asserting logical 0 at output 92. This has the effect of connecting the lower drive
motor 14 to the motor motion sensor 48 whilst applying the relative high voltage the
upper drive motor 12. Similarly the image display medium may be scrolled in the downward
direction using the scroll down function by applying logical 1 to output 92 and 96
and applying logical 0 to output 94. The hold function is utilised when an image 23
is positioned correctly for viewing on the scrolling apparatus, to apply a small tension
to the image display medium and hold the image in the correct position. This is accomplished
by applying a relative low voltage to both the upper and lower drive motor input 70,
72 simultaneously. Figure 8 shows the logic conditions at outputs 92. 94 and 96 necessary
to accomplish this function.
[0023] Control circuit 100 is also provided with a motor motion sensor input 82. During
motion of the image display medium 24 within the scrolling apparatus 10, only one
of the upper and lower drive motors is energised at any particular time. However,
since the upper and lower drive motors are rotatably coupled to each other by means
of the image display medium 24 wound upon the upper and lower spools 16, 18, when
one of the drive motors is energised to wind the image display medium upon its spool
the other drive motor also rotates by virtue of the image display medium unwinding.
Thus, motion of the image display medium 24 may be sensed by examining the back emf
produced by the rotation of the motor which is not energised. This back emf signal
46 may be easily detected by motor sensor 48 by means of relay terminals 71 and 73.
The motor motion sensor signal is amplified by a buffer amplifier 50 and fed to the
control circuit 100 as the motor motion sensor input 82.
[0024] The display apparatus of the first embodiment may also be controlled manually by
switching an automatic/manual switch 54 to its manual position. With switch 54 in
the manual position the scrolling apparatus 10 is no longer controlled in accordance
with DTMF signals from the sound reproduction means. With the switch in the manual
position the logic signal indicating that the next image in the sequence should be
displayed is provided in accordance with a manual delay selector 38 and manual delay
timer 52. The manual delay selector 38 may be in the form of a thumb wheel switch
which provides a manual delay selector input 78 to the control circuit 100. When the
value of manual timer input 84 from the manual delay timer 52 reaches the value of
the manual delay selector input 78 the control circuit 100 initiates movement of the
image display medium to display the next image 23 in the sequence of images.
[0025] Figure 4 shows a simplified flow chart 102 of the operation of control system 31
under normal conditions. The procedure of flow chart 102 requires that the pre-recorded
sounds and control signals reproduced by the sound reproduction means 6 playable in
repeatable fashion. The pre-recorded sounds are recorded in sequence corresponding
to the sequence of images to be displayed, followed by pre-recorded sounds in reverse
sequence. Only three different control signals are required to be reproduced by the
sound reproduction means. One control signal is required to initiate movement of the
scrolling apparatus to display the next image 23 in the sequence, and another control
signal is required to instruct the control system 31 to display the previous image
in the sequence. The final control signal forces the scrolling apparatus to rewind.
These control signals are pre-recorded together with the aforementioned sounds, at
appropriate points on the tape.
[0026] Steps 105 to 107 of procedure 102 ensure that the image display medium 24 is rewound
(ie. wound upon one spool only) such that the first image in the sequence of images
is displayed by the visual display means. This is accomplished by energising the lower
drive motor 14 whilst detecting the back emf of the upper drive motor 12. At steps
106 and 107 the motion of the spools 16, 18 and the image display medium 24 is sensed
using the detected back emf of the upper drive motor 12 via terminal 71 motor senor
48 and buffer amplifier 50. When the image display medium 24 is completely rewound
rotational movement of upper spool 16 and the shaft of upper drive motor 12 ceases,
and the back emf sensed at the motor motion sensor input 82 is reduced to zero. A
back emf of zero from the upper drive motor 12 while the lower drive motor 14 is still
energised is an indication that the image display medium 24 is completely rewound,
and this is the condition examined at step 107. At this time the forward scrolling
direction is set to the upward direction (step 107a) such that the image display medium
24 is progressively wound upon the upper spool 16. Steps 108 and 109 scroll the image
display medium 24 forward until a stop tab corresponding to the first image in the
sequence of images is sensed by the optical sensor 15. This ensures that the image
23 is displayed correctly aligned on the diffuser 140. At steps 110 and 111 the control
apparatus waits for a move pulse control signal from the sound reproduction means
via the audio buffer amplifier 34 and the DTMF audio decoder 36. When the move pulse
is received the scrolling apparatus scrolls the image display medium 24 in the required
direction to display the desired image 23 in the sequence of images. Steps 113 and
114 ensure that the image display medium is not at its end, and if it is not then
the desired image in the sequence is scrolled to alignment as indicated by the stop
tab (step 109). When the end of the sequence of images as been reached (step 114)
the control system 31 acts to reverse the scrolling direction such that the forward
direction of scrolling becomes the downward direction. At step 119 the control circuit
100 checks for a fault condition, and if a fault is detected an alarm condition output
90 is energised to sound a buzzer 74 via a buzzer drive amplifier 64 (Figure 3). An
example of such a fault condition is if more than five reverses of scrolling direction
are carried out within one minute. If no fault condition exists and no rewind tone
is received at step 119a then the procedure returns to step 108 whereupon the images
are again displayed, in reverse sequence order, in a manner similar to that described
above. If a rewind tone is received at step 119a then the procedure returns to step
105. Using an appropriate pre-recorded audio tape and procedure 102 the display apparatus
2 may operate continuously, alternately displaying the images in forward sequence
order and reverse sequence order, accompanied by the corresponding sounds from the
sound reproduction means.
[0027] Figure 5 shows a modified operating procedure 120 which is appropriate to be used
when control system 31 is placed in the manual mode by switch 54. At steps 122 to
124 the image display medium 24 is rewound on to the lower spool 18, as in procedure
102. During steps 125 to 131 the images 23 are displayed individually in sequence,
the next image in the sequence being displayed when a move pulse is received (steps
127 and 128). In this case, the move pulse control signal may be received from either
the audio tape via the DTMF audio decoder 36 or from the manual delay timer 52. When
the end of the sequence of images is reached, as indicated by the back emf of the
motor not being driven (steps 130 and 131), and no fault condition exists (step 133),
the procedure returns to step 122 where the image display medium 24 is again rewound
and the procedure repeated.
[0028] Figure 9 shows scrolling apparatus 10 of the visual display means 8 of a second embodiment
of the present invention, where reference numerals in common with Figure 2 denote
similar items. The scrolling apparatus 10 of the second embodiment differs from the
scrolling apparatus of the first embodiment in several respects. To aid in guiding
the image display medium 24 the scrolling apparatus 10 is provided with one or more
tractor feed devices 164 along each edge of the image display medium 24. The image
display medium is also provided with a corresponding series of guide holes 166 along
each of its edges. In use, as the image display medium 24 is scrolled from one of
spools 16, 18 to the other, the edge of the image display medium 24 passes through
the respective tractor feed device 164 wherein the guide holes 166 engage with guide
projections 172 of the tractor feed device. Figures 11 and 12 show side and end views
of a typical tractor feed device, as are commonly used in tractor paper feed computer
printers. A continuous flexible belt 180 is contained on cylindrical rotatable spools
(not shown) which are arranged in a coplanar parallel orientation, the belt being
provided with guide projections 172. The flexible belt 180 is rotatable around the
spools such that the guide projections 172 follow a path through a groove 176 formed
in an upper lid portion 178 of the tractor feed device 164. In use, the guide projections
172 engage the guide holes 166 of the image display medium 24 at one end of the tractor
feed device 164 so as to guide the edge of the image display medium 24 along the tractor
feed device 164 to the other end of the device. An arrangement such as this, with
one or more tractor feed devices along each edge of the image display medium 24 in
the scrolling apparatus 10 allows good tensioning of the image 23 as it passes between
spools 16 and 18.
[0029] Figure 10 shows a side cross-sectional view of the mechanical arrangement of the
image display means 8 of the second embodiment, where reference numerals in common
with Figure 7 denotes similar items. The apparatus operates essentially the same as
that described in relation to Figures 6 and 7, except in this embodiment cylindrical
guide bars 144 are not provided adjacent the upper and lower spools 16, 18. In this
embodiment the image display medium 24 passes from one spool 16, 18 directly over
perspex diffuser 146, provided in the space between spools 16 and 18, and onto the
other spool. The perspex diffuser 146 is provided in close proximity to the spools
16, 18 to allow the image display medium 24 to be guided easily over the diffuser
146 without the aid of guide bars.
[0030] Figure 13 shows a length of the image display medium 24 containing a sequence of
images 23, in accordance with the second embodiment of the present invention. The
second embodiment allows the images 23 of the image display medium 24 to be divided
into image groups 169. The image groups 169 are delimited by a start tab 170 located
in the lower left hand corner of an image 23 adjacent the first image 167 in a group
169, and an end tab 168 located in the upper right hand corner of the first image
167 in a group 169 adjacent the last image 171 in the previous group 169. The start
tabs 170 co-operate with optical start sensor 160 (Figure 9) to indicate the first
image 167 group of images 169. The end tabs 168 cooperate with an optical end sensor
162 (Figure 9) to indicate the last image 171 a group of images 169. When the first
image 167 of a group of images 169 is displayed by the scrolling apparatus (for example,
the image 170 is adjacent the diffuser 146 (Figure 10)) the start tab 170 is immediately
adjacent the optical start sensor 160. When the last image 171 of a group of images
169 is being displayed the end tab 168 is immediately adjacent the optical end sensor
162.
[0031] Figure 14 shows control means 401 provided in accordance with the second embodiment
of the present invention. The control means 401 comprises four major components: control
logic 403. an internal control panel 182, a sound recording and reproduction means
406 and a function select timer section 425. These four major sections are interconnected
to provide electrical control signals to the upper and lower drive motors 12, 14.
[0032] The controliing functions of the control means 401 are provided by the control logic
section 403. The control logic section 403 receives inputs from the internal control
panel 182 the sound reproduction means 406, the function timer section 425 and the
optical sensors 15, 160 and 162. Incoming signals from the start sensor 160, the stop
sensor 15 and the end sensor 162 are processed in the sensor input processing means
402, before being forwarded to the main logic control 400. The senor input processing
402 contains de-bounced op-amp stages to amplify and filter the signals from the sensors
15, 160 and 162. The sensor input processing also receives motor back emf signals
from the upper and lower drive motors 12, 14 via motor control section 404. The back
emf signals from the upper and lower drive motors are also filtered and amplified
and converted to a digital signal before being fed to the main logic control 400.
The main logic control 400 also receives input from the internal control panel 182
which provides user selectable option signals to the main logic control 400 to change
the manner in which the scrolling apparatus 10 is controlled by the control means
401. The main logic control 400 also receives input signals from the sound reproduction
means 406 and the function timer section 425.
[0033] The sound reproduction means 406, in the second embodiment of the present invention,
comprises a digital voice recorder and playback device 410 coupled to semiconductor
memory 408. Figure 15 shows a more detailed schematic diagram of the sound reproduction
means 406 in accordance with the second embodiment. Control inputs 442 are received
by a logic control section 436 from the main logic control 400. The logic control
436 performs decoding logic operations on the control inputs 442 in order to select
one of a plurality of memory banks 428 of the semiconductor memory 408. The logic
control 436 also provides control signals to a sound control means 430. When the sound
control means 430 is placed in record mode, a sound signal at an analog input 440
is amplified by an amplifier stage 434 and passed to the sound control means 430 where
it is converted into a digital signal. The digitised sound signal is then stored sequentially
in the memory bank 428 selected by the logic control 436 for retrieval at a later
time. Then, when the sound control means is instructed to reproduce the recorded sounds,
the stored data in selected memory bank 428 is retrieved sequentially via the digital
data/control bus by the sound control means 430. The retrieved digital data is converted
into an analog signal by a digital-to-analog converter, which signal is then amplified
and filtered by op-amp stage 432, the amplification of which may be varied by potention-meter
200. The amplified and filtered analog output 438 is then fed to a speaker 414 via
an on/off control relay 416.
[0034] The second embodiment utilises a single chip continuously variable slope delta-modulation
(CVSD) voice recorder (such as TMS 3477 from Texas Instruments) for use as sound control
means 430. Such a single chip voice recording/playback controller interfaces directly
with semiconductor memory 428 for ease of use and construction. The second embodiment
utilises four one-megabit semiconductor memory chips for the memory banks 428 of storage
memory 408, which allows approximately 1 minute 40 seconds of sound reproduction when
the sound control 430 is set to 32 kilohertz data sampling frequency.
[0035] Sounds and control signal tones are initially recorded on magnetic tape for use with
a tape player 412 (Figure 14). When the audio signal is to be stored in the digital
memory the tape player 412 is coupled to the analog input 440 and a record signal
is sent from the main logic control 400 to logic control 436 via the control input
442. Since the semiconductor memory banks 428 comprise volatile RAM memory a battery
backup electrical supply is provided in the sound reproduction means so that audio
signals stored in the memory 408 can be retained even if electrical power is switched
off to the rest of the control means 401. The memory banks 428 may be sequentially
pre-recorded with a single continuous audio signal, with logic control 436 automatically
switching from one memory bank to the next during record and playback of the audio
signal. Alternatively, the memory banks may be stored with up to four separate audio
signals, one in each of the memory banks 1 to 4. This can allow up to four different
audio voice messages to be pre-recorded and played back, each with its own pre-recorded
control signals. A further advantage of the digital audio storage technique is that,
unlike a normal magnetic tape sound reproduction device, no time is required to rewind
the audio message from the end back to the beginning. The digital sound reproduction
means is also much simpler in construction and more reliable than a mechanical sound
reproduction means such as a magnetic audio tape player.
[0036] The control means 401 (Figure 14) is also provided with a function timer section
425. This includes a daily on/off timer 424 and a group select timer 426. The daily
on/off timer 424 may be selectively programmed by the user, via the internal control
panel 182 and main logic control 400, to enable the display apparatus to be automatically
activated and deactivated at predetermined times during the day. For example, the
daily on/off timer may be pre-programmed to switch the apparatus on at 9 o'clock in
the morning and switch the apparatus off at 5 o'clock in the evening. The daily on/off
timer 424 contains a 24 hour electronic clock, memory to store switch-on and switch-off
times and a comparator stage to determine the switch-on and switch-off times by comparison
of the electronic clock output and the stored switch-on and switch-off times in the
provided memory. When the comparator within the daily on/off timer stage 424 indicates
correspondence between the electronic clock output and the stored switch-on time a
switch-on signal is sent to the main logic control 400. Similarly, when the comparator
determines correspondence between the pre-stored switch-off time and the electronic
clock output the timer 424 is use a switch-off signal to the main logic control 400.
When a switch-on signal is received by the main logic control 400 the control means
401 begins a procedure illustrated by the flow chart in Figure 18. When a switch-off
signal is received the main logic control 400 enters a reset state and waits for a
switch-on signal from the on/off timer 424.
[0037] The function timer section 425 also contains group select timer 426 which receives
an input of the electronic clock time from the daily on/off timer 424. The group select
timer 426 operates in a manner similar to the daily on/off timer 424 only, instead
of indicating times for apparatus to switch on and switch off, the group select timer
426 indicates times at which the apparatus should display different groups of images.
[0038] If the image display medium 24 comprises a number of image groups 169, and the sound
reproduction means 406 is pre-stored with a number of difference voice messages in
the memory banks 428, then the group select timer 426 may be programmed to instruct
the main logic control 400 to switch from one image group 169 and memory bank 428
to another image group and memory bank at a predetermined time. For example, if the
image display medium 24 is provided with four distinct image groups 169 and the sound
reproduction memory is pre-recorded with four separate voice messages, then the group
select timer 426 may be pre-stored with four 24 hour clock times at which the image
display apparatus is to switch from one image group 169 and voice message stored on
a memory bank 428 to the next image group and voice message.
[0039] The control means 401 also comprises a touch plate 422 which may be located on the
front of the box enclosure 136, adjacent to the transparent portion for image display.
The touch plate 422 is coupled to a touch switch circuit 420 such that, when a person
touches the touch plate 422, the touch switch circuit 420 senses a change of capacitance
in the touch plate 422 and energises a relay 416 which connects the speaker 414 to
the sound reproduction means 406. When the touch switch circuit 420 senses the change
in capacitance of the touch plate 422 the touch switch circuit 420 also issues a signal
to the main logic control 400 which initiates a preset voice timer. When the voice
timer expires the main logic control 400 issues a signal to the touch switch circuit
420 which then de-energises the speaker relay 416. Alternatively, instead of a timer,
a counter may be utilised to de-energise the speaker relay 416 after a predetermined
number of images have been advanced. The number of images which have been advanced
may be counted using the output of the optical stop sensor 15 as an indication of
the movement of images.
[0040] Figure 16 shows controls which may be available on an internal control panel 182
of the second embodiment. The internal control panel 182 includes a start push button
switch 186 which activates and deactivates the image display apparatus. A run led
188 indicates whether the sound reproduction means 406 is activated or deactivated.
The control panel also includes a record/play toggle switch 196 to control the sound
reproduction and record means 406 to switch between record and playback modes of the
digital voice recorder 410. Another toggle switch 194 enables the apparatus to be
controlled by either control signals from the sound reproduction means 406 or signals
from the delay timer 52 contained in the control logic section 403 of the control
means 401. A thumbwheel switch is coupled to the delay timer 52 to enable the user
to preset a time for which each image 23 will be displayed when the apparatus is in
timer mode. Another thumbwheel switch 190 enables the user to preset the voice counter
value for the number of images during which the relay switch 416 to the speaker 414
remains closed after the touch switch circuit 420 has been activated by the touch
plate 422. An input jack 198 is provided on the control panel 182 for connection of
the tape player 412 to allow pre-recorded audio signals to be transferred from the
tape player 412 to the digital sound reproduction means 406. An output level potentio-meter
200 of the control panel 182 allows adjustment of the level of the analog output 438
to the speaker 414. The control panel 182 is also provided with timer programming
control push buttons 206, week day indicators 204 and time clock display 202. The
controls 206 allow timer values to be entered for each day of the week, as indicated
by the week day indicators 204, for use in the daily on/off timer 424 and the group
select timer 426. A reset push button 208 is also provided which, when pressed, places
the control logic into a reset state, and rewinds the images to the physical beginning
of the image display medium 24.
[0041] An auxiliary control panel 184 contains three push buttons for use in loading images
23 onto the scrolling apparatus 10. A forward push button 210, when pressed, causes
the motor control 404 to provide a low voltage input to the lower drive motor 14.
Similarly a backward push button 212, when pressed, causes the upper drive motor 12
to be provided with a low voltage input. When the low voltage input is provided to
either the upper or lower drive motor 12, 14 the upper or lower spool 16, 18 is caused
to rotate slowly, thus slowly moving the image display medium 24 in one direction
or the other. Using this slow movement of the image display medium the joining portion
161 between two images 23 of the image display medium 24 may be accurately positioned
to allow one image 23 to be replaced by another image with the image display medium
still wound upon spools 16, 18. To change one image 23 for another, the joining portion
161 would ordinarily be advanced to a position between two tractor feed devices 164
such that the two images 23 adjoining the portion 161 are held in place by the tractor
feed devices 164. Whilst in this position the adhesive tape or "velcro" strips used
to join the images 23 may be removed and another image placed on the tractor feed
device guiding projections 172 to accurately align the new image with the adjoining
image. A release push button 214 is also provided on the auxiliary control panel 184
which acts to slowly drive the upper and lower drive motors 12 and 14 in opposite
directions to reduce the tension on the image display medium 24 to enable easy replacement
of images.
[0042] Figure 18 shows a flow chart 301 of the operation of control system 401 of the second
embodiment of the present invention. Throughout the flow chart the following shorthand
notation is utilised:
BOTSNS designates that a signal has been issued from the start sensor 160 indicating
that the first image in a group of images 169 is now displayed;
EOTSNS designates that a signal has issued from the end sensor 162 indicating that
the final image 171 in a group of images 169 is now displayed;
STPSNS designates that a signal has issued from the stop sensor 15 indicating that
the image 23 being displayed is correctly aligned;
UPWARDS designates a direction of movement of the image display medium wherein the
image display medium 24 is unwound from lower spool 18 and wound upon upper spool
16;
DOWNWARDS designates a direction of movement of the image display medium 24 wherein
it is unwound from upper spool 16 and wound upon lower spool 18;
RUN designates a condition of the upper and lower drive motor inputs such that the
image display medium 24 is moved in the upwards or downwards direction;
STRT VOICE designates that the sound reproduction means 406 has begun producing audio
output signals; and
TONE designates a control signal from the sound reproduction means 406 which is decoded
in a DTMF decoder contained in the main logic control 400.
[0043] The procedure of flow chart 301 begins at step 300 wherein the control means 401
is held in a reset state where both upper and lower motors are at rest. At step 302
the main logic control 400 issues a control signal to the motor control 404 which
acts to drive the lower motor 14 until the entire image display medium 24 is wound
upon lower spool 18. As in the first embodiment, when one of the upper and lower drive
motors are energised the back emf from the motor which is not energised may be used
as an indication of the movement of the image display medium 24. At step 304 the UPWARDS
direction is selected and during step 306 the image display 5 medium is moved in the
selected direction until the first image 167 in a group of images 169 is displayed.
At step 308 the control logic 403 determines which of the four pre-stored image groups
should currently be displayed and compares it with the image group which is selected
(initially group one). If the image group which should be displayed does not match
the selected image group step 310 acts to increment the selected image group and corresponding
memory bank 428 of the sound reproduction means 406. The image display medium 24 is
then advanced to the beginning of the next image group as indicated by BOTSNS and
the comparison of step 308 is repeated until the image group which is selected matches
the image group to be displayed. If the internal control panel 182 is set to timer
mode by toggle switch 194, step 312 directs the procedure to step 314 which acts to
initiate delay timer 52. When the delay timer expires step 316 directs the procedure
to advance the image display medium to the next image 23 in the group of images 169
(step 318). If the upwards direction is currently selected (step 320) and the end
of a image group is sensed (step 326) then the direction of movement of the image
display medium 24 is reversed at step 328. Similarly, if the downwards direction is
currently selected and the beginning of a image group is sensed (step 322) then the
direction is reversed so that the upwards direction becomes valid (step 324). The
procedure then returns to step 312 and begins again. If the voice mode has been selected
via toggle switch 194 of internal control panel 182 then step 330 acts to start the
sound reproduction means 406. By virtue of steps 306, 308 and 310, the memory bank
428 of the sound reproduction means 406 corresponds to the image group which is currently
displayed. When a control signal (TONE) is received (step 332) it is decoded by the
DTMF decoder and determined to be one of an up tone, a down tone or a rewind tone
(steps 334. 336 and 338). If none of these tones are recognised then the signal is
ignored (step 340) and the main logic control 400 waits for another tone to be received
at step 332. If the tone is an up tone (step 334) the upwards direction is selected
at step 342 and the image display medium 24 is advanced to the next image in the sequence
in the upwards direction (step 318). If the tone detected is a down tone (step 336)
then the downwards direction is selected at step 344 and the image display medium
24 is advanced to the next image in the sequence in the downwards direction (318).
If the 5 tone detected is a rewind tone (step 338) then the downwards direction is
also selected (step 346) and step 348 acts to advance the image display medium 24
until the beginning of the selected image group 169 is sensed (step 348). Steps 320
to 328 are then carried out as in the timer mode.
[0044] Using the procedure illustrated in flow chart 301 the images 23 in a group 169 can
be sequentially displayed in upwards sequence followed by downwards sequence continuously,
accompanied by corresponding voice messages from the sound reproduction means 406
which issues the appropriate up and down tones. When the images of the group 169 are
displayed in downwards sequence the tone issued from the pre-recorded audio signal
of the sound reproduction means 406 to move from the penultimate image to the final
image in the sequence (for example, the first image of the group) may be a rewind
tone instead of a down tone. This restores both the image group 169 to the first image
in the group and the voice message of the sound reproduction means to the beginning,
thus ensuring that the voice message and the image sequence are re-synchronised in
the event that an up or down tone was missed during the display of the sequence.
[0045] Figure 19 shows a flow chart 371 which is carried out by the main logic control 400
continuously during the operation of the control system 401. This procedure whether
the scrolling apparatus is in a jammed condition. If either or both of the upper and
lower motors 12, 14 are being driven (step 362) then a movement sensor is examined
to determine whether the image display medium 24 is in fact being moved (step 364).
The movement sensor may, as in the first embodiment, comprise the upper or lower motor
back emf, or may alternatively comprise a shaft encoder or pulse counter. A pulse
counter movement sensor may easily be incorporated in the second embodiment using
an optical sensor to sense movement of the guide holes 166 along one edge of the image
medium past a stationery light source. If movement is sensed at step 364 then a jam
timer is reset at step 374 and step 362 is repeated. If one of the upper and lower
drive motors 12, 14 are being driven and no movement is sensed from the movement sensor
(step 364) then the jam timer is examined to determined whether it has been previously
set (step 366). If the jam timer has not been set then step 372 acts to set the jam
timer and return the procedure to step 362. If the timer has been set (step 366) and
the time has expired (step 368) this indicates that one of the upper and lower drive
motors 12, 14 have been energised for a predetermined time without any movement of
the image display medium 24 taking place, thus indicating a jammed condition (step
370). If the jam timer has not expired (step 368) then the procedure is again returned
to step 362.
[0046] Figure 20 shows a flow chart of a procedure which may be carried out by the control
means 401 to change from one image group 169 to another image group. When the group
select timer 426 expires (step 360) the main logic control 400 determines if the current
group is the last of the preset image groups at step 352. If the current image group
169 is the last of the groups then step 354 acts to rewind the image display medium
24 to the beginning of the first of the image groups 169. Step 360 similarly acts
to set the control inputs 442 to logic control 436 of the sound reproduction means
406 to select the memory bank 428 corresponding to the first image group 169. If,
at step 352, the main logic control 400 determines that the current image group 169
is not the last of the preset image groups, then the upwards direction is selected
at step 356 and the image display medium 24 is advanced in the upwards direction until
the beginning of the next image group 169 is detected by the optical start sensor
and the optical stop sensor (step 358). Step 360 is then carried out to select the
next of the memory banks 428, corresponding to the new image group 169.
[0047] With reference to Figure 29, there is shown a third embodiment of the image display
apparatus. indicated by reference number 600. The basic operation of the third embodiment
of the image display apparatus is essentially the same as that described in relation
to the second embodiment, however including several added features. A visual display
means 604 comprises a pair of parallel spaced spools each driven by a respective electric
motor to enable a plurality of images joined end to end to form a length of image
display medium to be coiled and uncoiled upon the spools and displayed therebetween,
as described with reference to Figures 2, 9 & 10, for example. The electric motors
of the visual display means 604 are controlled by a centralised control means 602.
The control means 602 comprises a microprocessor or microcontroller having input and
output ports for receiving data and issuing control signals to and from the various
components coupled thereto, one of which is the visual display means 604, which receives
signals via control circuitry 610. The microprocessor or micro controller of the control
means 602 includes non volatile memory such as ROM or EPROM containing controlling
instructions for the micro processor or micro controller, and RAM for storing and
retrieving information relating to the operation of the image display apparatus.
[0048] The central control means 602 issues control signals to the electric motors of the
visual display means 604 by way of the control circuitry 610, which comprises, for
example, digital-to-analog converting circuitry and operational amplifiers, for changing
digital control signals from the control means 602 into appropriate analog signals
to drive or control the electric motors. Image movement and position sensors 606 derive
data from the movement and position of the images in the visual display means 604,
and forward such data to the central control means 602 by way of analog-to-digital
and decoding circuitry 612. The apparatus 600 also includes audio storage circuitry
608, such as the digital sound circuitry illustrated and described with reference
to Figure 15, which is controlled by signals from the control means 602, and which
outputs sound by way of a speaker 620. The audio storage circuitry 608 also outputs
sound signals to a DTMF decoder 614 which decodes the sound signals and issues data
to the control means 602 in the way previously described. A control panel 516 is also
included, comprising a multiple line alpha-numeric display 626, and a key pad 624.
The alpha-numeric display 626 allows the control means 602 to output information to
a user of the apparatus, such as menu options relating to the control of the apparatus
600, or prompt for information from the user to be entered by way of the key pad 624.
[0049] One of the menu options selectable from the key pad 624 is the option to place the
image display apparatus 600 into a remote control manual mode, which utilises an input
from a remote control 618. When in the remote control manual mode a signal issued
on remote line 618, by way of a wired push button switch, is received by the control
means 602, which causes the visual display means 604 to advance to the next image
in the sequence of images.
[0050] As in the second embodiment, the changing of the display of images in the visual
display means 604 may be controlled either by way of control signals derived from
the audio storage means 608, or by way of timing signals generated within the control
means 602. When the latter method is adopted in the third embodiment, the display
time for each of the individual images may be programmed individually, and flowchart
650 for this procedure is illustrated in Figure 30. The programming begins at step
652 and at step 654 the image display medium is rewound to its beginning. The first
image of the first group of images is then displayed at step 656. Whilst the first
image is being displayed the control means 602 utilises the alpha numeric display
626 to prompt a user to input a display time delay for the image currently displayed
(step 658), in response to which the user inputs a time delay in seconds by way of
the key pad 624. The delay time inputted at step 658 is stored by the control means
602 (step 660) in RAM memory, in a location thereof which is associated by the control
means 602 with the image currently on display. At step 662 the control means determines
whether the currently displayed image is the last image in the entire sequence of
images contained in the visual display means 604, and if the last image is detected
the procedure is terminated at step 664. If the last image is not detected at step
662 the next image in the sequence of images is displayed by the visual display means
604 (step 666). The control means 602 again prompts the user to input a display time
delay for the image displayed (step 668) and the delay time programmed by the user
is stored in memory at step 670. Thereafter the procedure returns to step 662 and
repeats steps 662 to 670 until each of the images in the sequence has been allocated
a display time delay. Once having been programmed in this manner, the control means
602 is then able to control the visual means 604 such that each image in the sequence
is displayed for an amount of time corresponding to that stored in the memory location
corresponding to that image.
[0051] One way in which the above procedure may be more easily facilitated is by providing
each image in the visual display means 604 with a label containing a unique barcode.
Such a barcode label may be provided on each image 23 (see Figure 2) in place of a
stop tab 13, positioned in a corner of the image 23. A barcode reader may then be
provided in a manner similar to optical sensor 15 (Figure 7), comprising a portion
of the image movement and position sensors 606. Barcode decoding circuitry (612) may
then be provided to receive signals from the barcode sensor to output the unique code
to the control means 602. In this way, the unique code derived from the barcode label
may be used by the control means 602 as an index to the memory location at which to
store the delay time for the corresponding image, during the programming procedure
650. The code may again be used during normal operation to retrieve the delay time
from the RAM memory.
[0052] The image display apparatus 600 is further provided with a vicinity movement sensor
622, which may be an ultrasonic or infared type detector of the type used in burglar
alarm detection systems. This feature allows the image display apparatus 600 to actively
operate only when movement of people is detected in the immediate vicinity of the
apparatus. By disabling movement of the images and de-energising the lights of the
visual display means 604 whilst no movement is detected in the vicinity of the apparatus
600, reduced power consumption and reduced wear and tear of both the apparatus and
the image display medium can be achieved. A procedural flow chart of operation of
the control means 602 utilising an input from the vicinity movement sensor 622 is
illustrated at 675 in Figure 31. At step 680 a movement timer is started, being initially
zero. As in all the timed functions in the third embodiment, the movement timer may
comprise an internal timer of the micro processor or micro controller of the control
means 602, or an elapsed time may be measured by way of an internal clock. If movement
is sensed by the detector 622 (step 684) the movement timer is reset at step 682,
and the procedure is returned to step 684 to examine for further movement in the vicinity.
If no movement is detected at step 684 the value of the movement timer is examined
(step 686) and if the timer value is greater than a pre-determined value (step 688)
the procedure continues to step 690. If the timer value is less than the preset value
the procedure returns to step 684 to determine any movement in the vicinity. Step
690 acts to pause the image delay timer such that no further movement of images takes
place, pauses the output of sound from the audio storage circuitry 608, and may de-energise
the illuminating lights of the visual display 604 if transparencies are displayed
such that the lights must be turned on to view the images. Having paused operation
of the visual display means 604, the control means 602 acts to monitor the movement
detector 622 (step 692), until some movement is detected. In this event, the lights
are again turned on, the sound is restarted and the image delay timer is also restarted
(step 694). Having returned to normal operation, the movement timer is reset (step
682) and the procedure returns to step 684.
[0053] With reference now to figures 21 to 28, a coiled display material 502 is shown particularly
in Figure 21, comprising generally a length of display material 508 coiled in overlapping
fashion upon a cylindrical spool 504. The display material may be, for example, a
length of transparencies formed from photographic film, posters, screen prints or
photographs. The edges 507 of the display material have disposed therealong lengths
of a spacing means 506. The spacing means 506 comprise generally flat elongate lengths
of a flexible material having a thickness indicated by t. The display material 508
is of elongate rectangular shape, and has elongate or side edges 507 with which an
edge 509 of the spacing means 506 is aligned.
[0054] In use, the display material 508 together with the spacing means 506 may be coiled
upon or uncoiled from the cylindrical spool 504 in the direction indicated by arrow
505 or 511 respectively. When the display material 508 and spacing means 506 are coiled
upon the spool 504 by rotation of the spool in the direction 505, subsequent lengths
of the display material 508 overlaps lengths of the material 508 previously coiled
upon the spool 504, creating layers of display material 508 around the spool 504.
Along the edges of the display material 508, where the spacing means 506 is disposed,
an inwardly facing surface 519 of the display material makes contact with, and is
coiled upon, an outwardly facing surface 521 of the respective underlying portion
of the spacing means 506. The spacing effect of the spacing means 506 at each edge
of the display material 508, whilst the material is coiled on the spool 504, prevents
the outwardly facing surface 517 of a particular layer of the coiled display material
508 from making contact with the inwardly facing surface of a subsequent layer of
the display material 508 when it is coiled thereupon. The narrow strips of the spacing
means 506 shown in Figure 21 are also sufficient to effect a gap between coiled layers
of the display material 508 in the portion of the display material which lies between
the spacing means 506 located at the edges of the elongate display material.
[0055] Figure 22 shows a side view of a portion of a display apparatus 510 where display
material in accordance with embodiments of the present invention may find use. Opposed
ends of the elongate display material 508 attach respectively to spaced and generally
parallel cylindrical spools 512, 514, whereupon portions of the display material 508
may be coiled on either or both of the spools 512, 514. This may be effected in such
a way that rotation of the spool 514 in a clockwise direction coils a portion of the
display material 508 and attached spacing means 506 on the spool 514. Such rotational
movement of this spool 514 causes the display material 508 in the region between spools
512 and 514 to move in a direction 518 towards the spool 514, and causes rotation
of the spool in an anticlockwise direction so as to uncoil a portion of the display
material 508 therefrom. Similarly, clockwise rotation of the spool 512 causes movement
of the display material 508 in a direction 516, then causes a portion of the display
material to be uncoiled from the spool 514 by clockwise rotation thereof. In this
way, an image formed on the portion of the display material 508 may be visible when
that portion is disposed in the region between the spools 512, 514, and next image
along the length of the display material 508 may be moved into the region between
the spools by rotation of the spools.
[0056] Figure 23 shows a length of display material 508 formed from sections 525 which are
joined end to end at joints 526. In this embodiment, the spacing means 506 is also
comprised of a plurality of sections along the edges of each section of display material
525. In this way, each section 525 of display material 508 may be provided with lengths
of the spacing means 506 along the edges thereof before being joined to other respective
sections 525. Alternatively, several joined sections 525 may be provided with a single
length of spacing means 506 along each edge thereof before being joined to another
series of similar joined section or sections.
[0057] Figure 24 shows a cutaway section two consecutive coils 530, 532 of a length of display
material 508, coiled upon a spool 504. The drawing particularly shows a length of
display material 508 provided with spacing means 506 having a thickness t, the portions
520, 522 of consecutive coils 530, 532 being separated by the spacing means 506 so
as to avoid damage to the surfaces of the display material 508 from contact therebetween.
[0058] The thickness t of the spacing means 506 may be in the range of a fraction of a millimetre
to several millimetres thick, and the thickness selected for the spacing means may
be somewhat dependant upon the width of the display material 508 to which it is to
be applied, since a thicker variety of spacing means 506 may be more effective in
separating the adjacent coils of a display material 508 having greater width. Each
length of the spacing means 506 may be constructed from a strip of a material such
as felt, rubber, foam rubber, plastic or, for example, the backing from a strip of
"velcro" material. The main criteria for selecting a material to be used for the spacing
means 506. is that it be flexible, of sufficient thickness to provide a gap between
adjacent coils of the display material, and that it be readily affixed to the particular
display material to be used. In that regard, the display material 508 may commonly
be constructed of a plastic film, such as may ordinarily be utilised as transparencies
for the display of images recorded thereon, or may be constructed from some other
flexible material such as cardboard or paper which has been laminated.
[0059] Referring now to Figures 25 and 26, there is shown a tool 540 which may be used to
accurately align adjacent sections 525 of a display material before the abutting joining
thereof. The tool comprises a rectangular backing plate 542 and two elongate clamping
members 544. The elongate clamping members 544 can be secured adjacent the longitudinal
edges of the backing plate 542 by means of threaded wing-nuts 546 which engage with
threaded bolts projecting from the top surface of the backing plate 542, and through
corresponding holes in the respective ends of the clamping members 544, there being
one bolt and wing-nut disposed at each end of each clamping member 544. The backing
plate 542 and clamping members 544 are constructed so as to be longer in their direction
of extent than the width of the sections 525 of the display material with which they
are to be used.
[0060] In use, two display material sections 525 are introduced into the tool 540, an cnd
of each section 525 being inserted between a respective clamping member 544 and the
backing plate 542, whilst the securing wing-nuts 546 are in a loosened position. Each
clamping member 544 is further provided with two aligning holes 548, which align with
corresponding holes in the backing plate 542 when the clamping member is secured by
the bolts and wing-nuts 546. The corners of the display material sections 525 are
also provided with aligning holes 548 which may be positioned to align with the corresponding
holes in the respective clamping member 544 and the backing plate 542. When a section
525 is so positioned, it may be held in alignment with the backing plate 542 and clamping
member 544 by means of dowel inserted in each hole 548. The holes 548 are so positioned
in the corners of the sections 525 and the tool 540 such that, when two display material
sections 525 are aligned by means of the holes 548, the end edges thereof abut along
a joining line 526. The sections 525 may then be clamped in position by tightening
the wing-nuts 546 on the clamping members 544, and the two sections 525 may be secured
together in their correct alignment by means of a length of adhesive tape 550.
[0061] The spacing means 506, being provided along the side edges of the display material
508, is effective to provide a gap between adjacent coiled layers of the display material
508, in the regions adjacent the side edges thereof. The gap between centre portions
of coiled layers of the display material 508, however, may be somewhat dependent upon
the stiffness of the coiled display material. In this regard, it has been found that
where the display material 508 comprises a plurality of sections 525 joined end-to-end
in abutting fashion, for example, with adhesive tape as hereinbefore described, the
lateral stiffness of the display material 508 may, in some instances, be somewhat
reduced in the region of the joint 526. This reduction in stiffness may be such as
to allow the display material 508 to bow or sag in a direction transverse to the axis
of the coiling spool, in the region of the joint 526, to such an extent that contact
is made between the display material in the centre portion of the region of the joint
526 and the centre portion of an adjacent coiled layer of display material 508.
[0062] Figure 27 shows a method of joining adjacent sections 560, 562 of display material
so as to avoid any difficulties which may be encountered with an abutting joint. In
this Figure, the adjacent sections 560, 562 are shown overlapping each other in a
region 570, an end portion of section 562 lying on top of an end portion of the section
560. Dashed lines 566 and 564 represent the end edges of the sections 560 and 562
respectively, whilst the region 570 lying therebetween is the region of overlap of
the two sections. The end edges 564, 566 are affixed to adjacent end portions of the
respective overlapping section 560, 562 by means of strips of flexible adhesive tape
568, in a manner similar to that hereinbefore described in relation to Figures 25
and 26.
[0063] The overlap 570 between the adjacent sections 560. 562 provides greater lateral stiffness
across the width of the display material 508 in the region of the joint 526, in comparison
to the abutting joint. The increased stiffness may be effective to eliminate the difficulties
of bowing or sagging of the display material in the centre portion in the regions
of the joints 526 between adjacent sections.
[0064] The overlapping joint between adjacent sections 560, 562 of the display material
508 described above, also enables the provision of a particularly simple aligning
and joining tool 540, as shown in Figure 28. The tool 540 is similar in construction
to that described in relation to Figures 25 and 26, however only one elongate clamping
member 544 is provided extending across the backing plate 542, centrally located with
respect to the longitudinal edges thereof. Aligning holes 548 are provided in the
corners of the adjacent sections 560, 562, such that alignment of the respective aligning
holes 548 of the adjacent sections places the adjacent sections 560, 562 in the necessary
relative positions to be joined by means of the strips of adhesive tape 568. This
alignment procedure may be effected by means of the tool 540 by alignment of the aligning
holes 548 of the sections 560, 562 with corresponding aligning holes 548 provided
in the clamping member 544 and backing plate 542. With the adjacent sections 560,
562 so positioned, being placed between the backing plate 542 and the clamping member
544 in its loosened position, the relative positioning may be secured by inserting
dowel sections in the aligning holes 548 of the clamping member 544 which extend through
the aligning holes 548 of both sections 560, 562 and the corresponding aligning holes
548 of the backing plate 542. The sections 560, 562 may then be clamped in position
by tightening the wing-nuts 546 on the clamping member 544, and the sections may then
be secured together in their correct alignment by applying lengths of adhesive tape
568 along the edges 564, 566.
[0065] It will appreciated from the foregoing description of the aligning tool 540 that
many varieties of securing means may be used in place of the bolts and wing nuts 546,
and that many different types of aligning means may also be used. For example, to
align the sections 525, there need not be provided aligning holes 548 into which a
dowel is inserted to secure alignment. Indeed, aligning marks may be merely provided
on both the display material section 525 and the holding member 544 or backing plate
542 with the holding member 544 being tightened against the backing plate 542 to hold
the section 525 in its correct alignment.
1. Control apparatus for use with image display means (10) which, in use, sequentially
displays images (23) of a selected group from a plurality of groups (169) of images,
said control apparatus comprising processing means (403) responsive to first control
signals to cause said image display means (10) to display a next image of said selected
group of images, and responsive to second control signals to cause a succeeding group
of images to become said selected group, wherein said second control signals are generated
by timer means (52, 425) at predetermined times of the day.
2. Control apparatus according to claim 1, wherein said first control signals are generated
at predetermined intervals by said timer means (52, 425).
3. Control apparatus according to claim 2, wherein a said predetermined interval is preselectable
for each image.
4. Control apparatus according to claim 1, including a sensing means (15) which, in use,
senses marker means (13) associated with each image (23) of a said group of images
(169) and generates a corresponding positioning signal.
5. Control apparatus according to claim 4, wherein said sensing means (15) comprises
an optical sensor, and said marker means comprises a reflective tab provided on each
image, or at least one hole provided adjacent a displayed portion of each image.
6. Control apparatus according to claim 3, including sensing means which in use senses
marker means associated with each image of a said group of images, said marker means
comprising coding means, wherein said sensing means generates a coding signal corresponding
to said coding means.
7. Control apparatus according to claim 6, wherein the coding means of at least each
image (23) in a said group of images (169) is unique to that image, and said codling
signal serves to identify a said image by way of said unique coding means, and wherein
said predetermined interval for each image is selected on the basis of said coding
signal.
8. Control apparatus according to claim 7, wherein said coding means comprises a barcode
and said sensing means (15) comprises a barcode reader.
9. Image display apparatus comprising image display means (10), and control means (401)
for controlling said image display means, said image display means, in use, sequentially
displaying images (23) of a selected group from a plurality of groups (169) of images,
said control means comprising processing means (400, 402) responsive to a first control
signal to cause said image display means (10) to display a next image of said selected
group of images, and responsive to a second control signal to cause a succeeding group
of images to become said selected group, wherein said second control signals are generated
by timer means (425) at predetermined times of the day.
10. Image display apparatus according to claim 9, wherein said first control signals are
generated by timer means (52) at predetermined intervals.
11. Image display apparatus according to claim 10, wherein a said predetermined interval
is preselectable for each image.
12. Image display apparatus according to claim 9, wherein each said group (169) of images
comprises a number of images (23) joined to form a length of images coiled, in use,
in overlapping fashion upon at least one of first (16) and second (18) spools, said
groups of images being joined sequentially to form a length of images such that the
last image of one such group of images is joined to the first image of the next group.
13. Image display apparatus according to claim 12, wherein said image display means (10)
includes motion means (12, 14), for effecting movement of an image (23) from the selected
group of images into a display area in which the image is, in use, displayed, said
motion means (12, 14) being controlled by said control means (401) in accordance with
said first control signals to rotate said second spool (18) when a said first control
signal is received by said control means, so as to coil a portion of said length of
images (24) upon said second spool (18) to move the next image in said selected group
of images into the display area.
14. Image display apparatus according to claim 13, including sensing means (15) which,
in use, senses marker means (13) associated with each image (23) in the selected group
of images and generates corresponding stop signals which are indicative of the position
of an image from the selected group of images in the display area, and wherein the
control means (401) controls said motion means (12, 14) in accordance with said stop
signals.
15. Image display apparatus according to claim 14, wherein said sensing means comprises
an optical sensor, and said marker means (13) comprises a reflective tab provided
on each image, or at least one hole provided adjacent the displayed portion of each
image.
16. Image display apparatus according to claim 11, wherein each image (23) in a said group
of images (169) is provided with coding means (13), and said apparatus includes sensing
means which in use generates a coding signal corresponding to said coding means, wherein
the coding means (13) of at least each image in a said group (169) of images is unique
to that image, and said coding signal serves to identify a said image by way of said
unique coding means, and wherein said predetermined interval for each image is selected
on the basis of said coding signal.
17. Image display apparatus according to claim 16, wherein said coding means (13) comprises
a barcode and said sensing means (15) comprises a barcode reader.
18. Image display apparatus according to claim 16, wherein said control means (401) is
responsive to a third control signal to cause the image display means (10) to display
the first image (167) in the selected group (169) of images, wherein said third control
signal is generated by comparing means (400) when said coding signal corresponds to
a predetermined signal.
19. Image display apparatus according to claim 14, wherein said control means (401) is
responsive to a third control signal to cause the image display means (10) to display
the first image (167) in the selected group (169) of images, further including counting
means (400) which in use receives said stop signals from said sensing means (15),
counts the number of said stop signals generated, and generates said third control
signal when said number of stop signs counted reaches a predetermined value.
1. Steuereinrichtung zur Verwendung mit einem Bildanzeigemittel (10), das in Gebrauch
aufeinanderfolgend Bilder (23) aus einer, aus mehreren Bildergruppen (169) ausgewählten
Gruppe anzeigt, wobei die Steuereinrichtung wenigstens ein Verarbeitungsmittel (403)
aufweist, das auf erste Steuersignale reagiert, um das Bildanzeigemittel (10) zu veranlassen,
ein nächstes Bild der ausgewählten Bildergruppe anzuzeigen, und das auf zweite Steuersignale
reagiert, um eine nachfolgende Bildergruppe zu veranlassen, als Gruppe ausgewählt
zu werden, wobei die zweiten Steuersignale durch wenigstens ein Zeitgebermittel (52,
425) zu vorbestimmten Tageszeiten erzeugt werden.
2. Steuereinrichtung nach Anspruch 1, bei der die ersten Steuersignale durch das Zeitgebermittel
(52, 425) in vorbestimmten Intervallen erzeugt werden.
3. Steuereinrichtung nach Anspruch 2, bei der das vorbestimmte Intervall für jedes Bild
vorauswählbar ist.
4. Steuereinrichtung nach Anspruch 1, mit einem Sensormittel (15), das in Gebrauch Markierungsmittel
(13) erfasst, die jedem Bild (23) der Bildergruppe (169) zugeordnet sind, und das
ein entsprechendes Positionierungssignal erzeugt.
5. Steuereinrichtung nach Anspruch 4, bei der das Sensormittel (15) einen optischen Sensor
aufweist und bei der das Markierungsmittel einen reflektierenden Vorsprung, der an
jedem Bild vorgesehen ist, oder wenigstens ein Loch aufweist, dass einem angezeigten
Abschnitt jedes Bilds benachbart angeordnet ist.
6. Steuereinrichtung nach Anspruch 3, mit einem Sensormittel, das in Betrieb Markierungsmittel
erfasst, die jedem Bild der Bildergruppe zugeordnet sind, wobei das Markierungsmittel
wenigstens ein Kodierungsmittel beinhaltet, wobei das Sensormittel ein dem Kodierungsmittel
entsprechendes Kodierungssignal erzeugt.
7. Steuereinrichtung nach Anspruch 6, bei der dass Kodierungsmittel wenigstens eines
Bilds (23) der Bildergruppe (169) einzigartig ist, so dass das Bild und das Kodierungssignal
dazu dienen, das Bild durch das einzigartige Kodierungsmittel zu identifizieren, und
wobei das vorbestimmte Intervall für jedes Bild auf der Basis des Kodierungssignals
ausgewählt ist.
8. Steuereinrichtung nach Anspruch 7, bei der das Kodierungsmittel einen Strichcode und
das Erfassungsmittel (15) einen Strichcodeleser aufweist.
9. Bildanzeigeeinrichtung mit einem Bildanzeigemittel (10) und einem Steuermittel (401)
zum Steuern des Bildanzeigemittels, wobei das Bildanzeigemittel in Gebrauch aufeinanderfolgend
Bilder (23) einer aus mehreren Bildergruppen (169) ausgewählten Gruppe anzeigt, wobei
das Steuermittel wenigstens ein Verarbeitungsmittel (400, 402) aufweist, das auf ein
erstes Steuersignal reagiert, um das Bildanzeigemittel (10) zu veranlassen, ein nächstes
Bild der ausgewählten Bildergruppe anzuzeigen, und das auf ein zweites Steuersignal
reagiert, um eine nachfolgende Bildergruppe zu veranlassen, die ausgewählte Gruppe
zu werden, wobei die zweiten Steuersignale an vorbestimmten Tageszeiten durch wenigstens
ein Zeitgebermittel (425) erzeugt werden.
10. Bildanzeigeeinrichtung nach Anspruch 9, bei der die ersten Steuersignale zu vorbestimmten
Intervallen durch wenigsten ein Zeitgebermittel (52) erzeugt werden.
11. Bildanzeigeeinrichtung nach Anspruch 10, bei der das vorbestimmte Intervall für jedes
Bild vorauswählbar ist.
12. Bildanzeigeeinrichtung nach Anspruch 9, bei der jede Bildergruppe (169) eine Anzahl
von Bilden (23) aufweist, die untereinander verbunden sind, um eine Länge aufgewickelter
Bilder zu formen, die in Verwendung überlappend auf wenigstens einer ersten (16) und
einer zweiten (18) Spule aufgewickelt sind, wobei die Bildergruppen sequentiell verbunden
sind, um einen Bilderstreifen zu bilden, so dass das letzte Bild einer solchen Bildergruppe
mit dem ersten Bild der nächsten Gruppe verbunden ist.
13. Bildanzeigeeinrichtung nach Anspruch 12, bei der das Bildanzeigemittel (10) Antriebsmittel
(12, 14) aufweist, um eine Bewegung eines Bilds (23) aus der ausgewählten Bildergruppe
in einen Anzeigebereich zu bewirken, in dem das Bild in Gebrauch angezeigt wird, wobei
das Antriebsmittel (12, 14) durch das Steuermittel (401) den ersten Steuersignalen
entsprechend gesteuert wird, um die zweite Spule (18) zu drehen, wenn das Steuermittel
das erste Steuersignal empfängt, um einen Teil des Bilderstreifen (24) auf die zweite
Spule (18) aufzuwickeln, um das nächste Bild der ausgewählten Bildergruppe in den
Anzeigebereich zu bringen.
14. Bildanzeigeeinrichtung nach Anspruch 13, mit wenigstens einem Sensormittel (15), das
in Gebrauch Markierungsmittel (18) erfasst, die jedem Bild (23) der ausgewählten Bildergruppe
zugeordnet sind, und das entsprechende Stoppsignale erzeugt, die für die Position
eines Bilds der ausgewählten Bildergruppe in dem Anzeigebereich gekennzeichnet sind,
und wobei das Steuermittel (401) das Antriebsmittel (12, 14) gemäß den Stoppsignalen
steuert.
15. Bildanzeigeeinrichtung nach Anspruch 14, bei der das Sensormittel einen optischen
Sensor aufweist und bei der das Markierungsmittel (13) einen an jedem Bild vorgesehene
reflektierenden Vorsprung oder wenigstens ein Loch aufweist, das dem angezeigten Abschnitt
jedes Bilds benachbart angeordnet ist.
16. Bildanzeigeeinrichtung nach Anspruch 11, bei der jedes Bild (23) der Bildergruppe
(169) mit Kodierungsmitteln (13) versehen ist, und wobei die Einrichtung ein Sensormittel
aufweist, das in Gebrauch ein dem Kodierungsmittel entsprechendes Kodierungssignal
erzeugt, wobei das Kodierungsmittel (13) wenigstens eines Bildes der Bildergruppe
(169) einzigartig für das Bild ist, und wobei das Kodierungssignal dazu dient, das
Bild durch das einzigartige Kodierungsmittel zu identifizieren, und wobei das vorbestimmte
Zeitintervall für jedes Bild auf der Basis des Kodierungssignals ausgewählt ist.
17. Bildanzeigeeinrichtung nach Anspruch 16, bei der das Kodierungsmittel (13) einen Strichcode
und das Sensormittel (16) einen Strichcodeleser aufweist.
18. Bildanzeigemittel nach Anspruch 16, bei dem das Steuermittel (401) auf ein drittes
Steuersignal reagiert, um das Bildanzeigemittel (10) zu veranlassen, das erste Bild
(167) der ausgewählten Bildergruppe (169) anzuzeigen, wobei das dritte Steuersignal
durch Vergleichermittel (400) erzeugt wird, wenn das Kodierungssignal einem vorbestimmten
Signal entspricht.
19. Bildanzeigeeinrichtung nach Anspruch 14, bei der das Steuermittel (401) auf ein drittes
Steuersignal reagiert, um das Bildanzeigemittel (10) zu veranlassen, das erste Bild
(167) der ausgewählten Bildergruppe (169) anzuzeigen, wobei außerdem ein Zählermittel
(400) vorgesehen ist, das in Gebrauch von dem Sensormittel (15) Stoppsignale empfängt,
die Anzahl dieser erzeugten Stoppsignale zählt und ein drittes Steuersignal abgibt,
wenn die Anzahl von gezählten Stoppsignalen einen vorbestimmten Wert erreicht.
1. Dispositif de commande destiné à être utilisé avec des moyens (10) d'affichage d'images
qui, en fonctionnement, affichent séquentiellement des images (23) d'un groupe sélectionné
parmi une pluralité de groupes (169) d'images, ledit dispositif de commande comprenant
des moyens de traitement (403) apte à répondre à des premiers signaux de commande
pour amener lesdits moyens d'affichage d'images (10) à afficher une image suivante
dudit groupe sélectionné d'images, et apte à répondre à des seconds signaux de commande
pour amener un groupe suivant d'images à devenir ledit groupe sélectionné, dans lequel
lesdits seconds signaux de commande sont produits par des moyens formant minuterie
(52, 425) à des instants prédéterminés de la journée.
2. Dispositif de commande selon la revendication 1, dans lequel lesdits premiers signaux
de commande sont produits à des intervalles prédéterminés par lesdits moyens formant
minuterie (52, 425).
3. Dispositif de commande selon la revendication 2, dans lequel l'un desdits intervalles
prédéterminés peut être présélectionnés pour chaque image.
4. Dispositif de commande selon la revendication 1, comprenant des moyens de détection
(15) qui, en fonctionnement, détectent des moyens de marquage (13) associés à chaque
image (23) de l'un desdits groupes d'images (169) et produit un signal de positionnement
correspondant.
5. Dispositif de commande selon la revendication 4, dans lequel lesdits moyens de marquage
(15) comprennent un capteur optique, et lesdits moyens de marquage comprennent une
patte réfléchissante prévue sur chaque image, ou au moins un trou prévu au voisinage
d'une partie d'affichage de chaque image.
6. Dispositif de commande selon la revendication 3, comprenant des moyens de détection
qui, en fonctionnement, détectent des moyens de marquage associés à chaque image dudit
groupe d'images, lesdits moyens de marquage comprenant des moyens de codage, lesdits
moyens de détection produisant un signal de codage correspondant auxdits moyens de
codage.
7. Dispositif de commande selon la revendication 6, dans lequel les moyens de codage
d'au moins chaque image (23) dans ledit groupe d'images (169) sont uniques pour cette
image et que ledit signal de codage sert à identifier ladite image à l'aide desdits
moyens de codage uniques, et dans lequel ledit intervalle prédéterminé pour chaque
image est sélectionné sur la base dudit signal de codage.
8. Dispositif de commande selon la revendication 7, dans lequel lesdits moyens de codage
comprennent un code à barres et lesdits moyens de détection (15) comprennent un lecteur
de code à barres.
9. Dispositif d'affichage d'images comprenant des moyens d'affichage d'images (10), et
des moyens de commande (401) pour commander lesdits moyens d'affichage d'images, lesdits
moyens d'affichage d'images affichant séquentiellement, en fonctionnement, des images
(23) d'un groupe sélectionné parmi une pluralité de groupes (169) d'images, lesdits
moyens de commande comprenant des moyens de traitement (400, 402) aptes à répondre
à un premier signal de commande pour amener lesdits moyens d'affichage d'images (10)
à afficher une image suivante dudit groupe sélectionné d'images, et aptes à répondre
à un second signal de commande pour amener un groupe suivant d'images à devenir ledit
groupe sélectionné, lesdits seconds signaux de commande étant produits par des moyens
formant minuterie (425) à des instants prédéterminés de la journée.
10. Dispositif d'affichage d'images selon la revendication 9, dans lequel lesdits premiers
signaux de commande sont produits par des moyens formant minuterie (52) à des intervalles
prédéterminés.
11. Dispositif d'affichage d'images selon la revendication 10, dans lequel l'un desdits
intervalles prédéterminés peut être présélectionné pour chaque image.
12. Dispositif d'affichage d'images selon la revendication 9, dans lequel chacun desdits
groupes (169) d'images comprend un nombre d'images (23) réunies pour former une longueur
d'images bobinée en fonctionnement, selon une disposition en chevauchement sur au
moins l'un d'un premier tambour (16) et d'un second tambour (18), lesdits groupes
d'images étant réunis séquentiellement pour former une longueur d'images de telle
sorte que la dernière image d'un tel groupe d'images est réunie à la première image
du groupe suivant.
13. Dispositif d'affichage d'images selon la revendication 12, dans lequel lesdits moyens
d'affichage d'images (10) comprennent des moyens de déplacement (12, 14) pour effectuer
le déplacement d'une image à partir du groupe sélectionné d'images, dans une zone
d'affichage dans laquelle l'image est affichée en fonctionnement, lesdits moyens de
déplacement (12, 14) étant commandés par lesdits moyens de commande (401) en fonction
desdits premiers signaux de commande pour faire tourner ledit second tambour (18)
lorsque ledit premier signal de commande est reçu par lesdits moyens de commande,
de manière à enrouler une partie de ladite longueur d'images (24) sur ledit second
tambour (18) pour déplacer l'image suivante dans ledit groupe sélectionné d'images
dans la zone d'affichage.
14. Dispositif d'affichage d'images selon la revendication 13, comprenant des moyens de
détection (15) qui, en fonctionnement, détectent des moyens de marquage (13) associés
à chaque image (23) dans le groupe sélectionné d'images et produisent des signaux
d'arrêt correspondants, qui sont indicatifs de la position d'une image parmi le groupe
sélectionné d'images dans la zone d'affichage, et dans lequel les moyens de commande
(401) commandent lesdits moyens de déplacement (12, 14) en fonction desdits signaux
d'arrêt.
15. Dispositif d'affichage d'images selon la revendication 14, dans lequel lesdits moyens
de détection comprennent un capteur optique et lesdits moyens de marquage (13) comprennent
une patte réfléchissante prévue sur chaque image, ou au moins un trou prévu au voisinage
de la partie affichée de chaque image.
16. Dispositif d'affichage d'images selon la revendication 11, dans lequel chaque image
(23) dudit groupe d'images (169) est pourvue de moyens de codage (13), et ledit dispositif
comprend des moyens de détection qui, en fonctionnement, produisent un signal de codage
correspondant auxdits moyens de codage, les moyens de codage (13) au moins de chaque
image dans ledit groupe (169) d'images est unique pour cette image, et ledit signal
de codage sert à identifier ladite image à l'aide desdits moyens de codage, et ledit
intervalle prédéterminé pour chaque image est sélectionné sur la base dudit signal
de codage.
17. Dispositif d'affichage d'images selon la revendication 16, dans lequel lesdits moyens
de codage (13) comprennent un code à barre et lesdits moyens de détection (15) comprennent
un lecteur de code à barres.
18. Dispositif d'affichage d'images selon la revendication 16, dans lequel lesdits moyens
de commande (401) sont aptes à répondre à un troisième signal de commande pour amener
les moyens d'affichage d'images (10) à afficher la première image (167) dans le groupe
sélectionné (169) d'images, ledit troisième signal de commande étant produit par des
moyens comparateurs (400) lorsque ledit signal de codage correspond à un signal prédéterminé.
19. Dispositif d'affichage d'images selon la revendication 14, dans lequel lesdits moyens
de commande (401) sont sensibles à un troisième signal de commande pour amener les
moyens d'affichage d'image (10) à afficher la première image (167) dans le groupe
sélectionné (169) d'images, et comprenant en outre des moyens de comptage (400) qui,
en fonctionnement, reçoivent lesdits signaux d'arrêt de la part desdits moyens de
détection (15), comptent le nombre desdits signaux d'arrêt produits et produisent
ledit troisième signal de commande lorsque ledit nombre de signaux d'arrêt comptés
atteint une valeur prédéterminée.