[0001] The invention relates to a lighting unit for illuminating an interior, a network
thereof and a method for lighting an interior using at least one lighting unit.
[0002] An effective bi-functional lighting unit provides light for working and other conditions
in addition to light for situation dependent illumination of interiors. These lighting
units creating the required light for a certain task on the one hand and a comfortable
atmosphere on the other hand are currently discussed. In relation to effectiveness
the use of LEDs (light emitting diodes) provides the possibility of a reduction of
the power consumption.
[0003] It is therefore an object of the invention to provide a possibility for illuminating
an interior effectively and situation dependent without a high power consumption.
[0004] This object is achieved by what is disclosed in the independent claims.
[0005] Preferred embodiments are:
A lighting unit for illuminating an interior, which comprises a housing with a side,
the predominant direction of which is towards the bottom and a top side, the predominant
direction of which is towards not the bottom, i.e. the top or ceiling of an interior
or the side walls of an interior. For providing a direct illumination, a direct illumination
lighting element is arranged at the bottom side. Preferably, by the direct illumination
element illumination is provided predominantly without any previous reflections at
elements external to the lighting unit inside the interior.
[0006] The direct illumination lighting element comprises at least one warm light LED unit,
from which light with a warm colour temperature, preferably in the range between 1,500
and 3,500 Kelvin is emitted. Further, the direct illumination lighting element comprises
at least one cold light LED unit from which light with a temperature above 3,500 Kelvin
is emitted. The LED unit may comprise one or more LED contained in one or more housings.
[0007] A direct illumination lighting element is e.g, used to provide a working light at
a desk. By mixing the light from the warm light LED unit and the cold light LED unit
the desired colour temperature can be achieved in addition to setting a desired intensity.
[0008] Further, at the top side an indirect illumination lighting element is provided from
which light is emitted towards the ceiling or side walls in order to illuminate the
interior as a whole. Preferably this is achieved by at least one reflection of the
emitted light e.g. at the ceiling.
[0009] The indirect illumination lighting element comprises at least a first LED and at
least second LED, which have different colours so that particularly a white colour
can be produced. Further, the indirect illumination lighting element comprises at
least one amber coloured LED in order to provide a nature colour in the interior as
far as possible. Preferably, the first and the at least second LED may be contained
together with the amber coloured LED in one common housing. Thus due to the small
distances a good mixing can be achieved. Further, less space is required for the accommodation
of the various LEDs.
[0010] Further, a connection element is provided for connecting the lighting unit to a control
unit 7. This connection element may provide a wired connection or a wireless connection
between lighting unit and control unit.
[0011] The lighting unit provides an effective illumination of a room in the sense that
e.g. working light on the one hand and an overall illumination of a room on the other
hand can be provided with a satisfying consumption of power, considerable production
costs, a wide range of possibilities to adapt to requirements of different interiors,
and a long lifetime.
[0012] According to an advantageous embodiment the lighting unit further comprises a control
unit by which the light intensity of the lighting unit is controlled. The control
unit may be positioned inside the lighting unit, e.g. in or at the housing or, in
the case of suspended lamps, at a point where the lighting unit is fixed at the ceiling
or at a position at the cable providing electrical current to the lighting unit.
[0013] Preferably, the control unit controls the light intensity of the lighting unit by
providing an internal control signal to the direct or indirect illumination element
from which it is transmitted to a subunit such as warm light LED unit, cold light
LED unit, first LED, second LED or amber LED. Alternatively or additionally, the control
signal is directly provided to each of these LEDs or LED units. This allows an accurate
control of brightness or intensity or light colour.
[0014] For this control the lighting unit may be equipped with an electrical circuit, which
provides in response to the internal control signal an adequate e.g. driving current.
There may be provided one common electrical circuit for all LEDs or LED units.
[0015] Alternatively, a separate electrical circuit may be provided for individual LEDs
or group of LEDs.
[0016] Instead or additionally to an wireless connection the connection element may provide
a transmission interface for a connection to a DALI bus system or any other digital
addressable lighting interface, across which the light intensity can be controlled.
[0017] According to another advantageous embodiment the lighting unit further comprises
a movement detector which provides a signal to the connection element if a movement
within a predetermined range of the lighting unit, e.g. a detection cone of the movement
detector, a light cone defined by the lighting unit, is detected. This allows a further
reduction of the energy consumption in that the light is switched off if no movement
is detected or it is switched between different dimming levels. By placing a movement
detector in or at the lighting unit, the movement is measured basically at the same
position where the light is emitted. Thus, the measurement has a high relevance for
controlling the light intensity. Further, a threshold may be applied to the movement
detector, thus that e.g. flying insects or movement of curtains do not lead to the
movement detector providing an output signal or that the output signal is not transmitted
further, e.g. from the connection element or control unit.
[0018] Additionally, it allows a coordinated setting of intensity of at least two lighting
units, if the movement detected by at least one lighting unit is communicated to the
at least other lighting unit by use of the connection element. This information may
be communicated either directly between the lighting units or via a central master
control unit. The central master control unit may be a separate unit or part of a
lighting unit, e.g. contained in its control unit.
[0019] A further advantageous embodiment is a lighting network comprising at least two lighting
units which are controlled by a master control unit which sends an external control
signal to at least one of the control units. Such a lighting network can be used to
create a predetermined illumination for an interior by setting brightness and/or the
temperature to a desired value. The external control signal is preferably transmitted
directly from the master control unit to the at least two lighting units. This allows
a fast control.
[0020] Alternatively, the externally control signal is transmitted from the master control
unit to a neighboured lighting unit and therefrom to the next neighboured lighting
unit. This allows in the case of wireless transmission a further reduction of sending
power. In the case of wired transmission, a simple protocol can be used without excessive
overhead data defining the modus of the transmission, i.e. the data to be transferred
are essentially the load data used for the control.
[0021] According to another embodiment an external control signal may be provided to the
control unit of a lighting unit which then provides an internal control signal to
at least one of direct or/and indirect illumination lighting element or individual
or groups of LEDs, such as first LED, at least second LED and amber LED. Thus the
light intensity and light temperature for the direct illumination lighting element
can be set on basis of the internal control signal.
[0022] Further, the colour of the indirect illumination lighting element can be adjusted
by adjusting the intensity of the first LED, second LED and/or amber LED separately,
Thereby, also the brightness of light emitted by the indirect illumination may be
adjusted together with the colour.
[0023] According to another embodiment an overall control signal may be provided to a master
control unit, which contains information on the overall illumination of an interior,
e.g. a lighting scenario such as conference or desktop work. In the master control
unit then an external control signal is created by using this overall control signal
and the external control signal is provided to at least one of the lighting units,
[0024] According to another embodiment the internal control signal or the external control
signal is created using in addition or only the movement detector signal, such that
an interior is illuminated only when actually a person is inside the interior.
[0025] Advantageous embodiments are described in the dependent claims.
[0026] Further aspects and advantages of the invention are disclosed in relation with the
accompanying drawings of which show:
Figure 1: an individual lighting unit;
Figure 2: a lighting network comprising several lighting units;
Figure 3: a processing of a movement detector signal;
Figure 4: an embodiment of a lighting unit as a suspended lamp;
Figure 5: a cross section of the lighting unit of Figure 4;
Figure 6: a top view on an embodiment of a bottom side PCB; and
Figure 7: a top view on a top side PCB 50.
[0027] In Figure 1 a lighting unit 1 is depicted which is formed as a suspended lamp fixed
on a ceiling. A housing 13 of the lighting unit 1 has a bottom side 2 directing towards
the floor of an interior and a top side directing towards the ceiling of an interior.
[0028] Due to the setup of the lighting unit 1 or/and the form of the housing 13 the bottom
side and the top side are defined such that the predominant direction is top or bottom,
but parts of the side may be directed under an angle alpha in relation to the vertical
line 17, thus that also light is not only emitted in vertical direction, even if a
spreading of light cones is neglected.
[0029] According to another embodiment, not shown, the bottom side is defined by the direction,
where a direct illumination is to be achieved and the top side by the direction where
no direct illumination is to be achieved, This may e.g. required for concert halls,
where the orchestra is positioned at some elevated position.
[0030] On the bottom side 2 a direct illumination lighting element 4 is positioned. This
direct illumination lighting element 4 may be positioned at one or various distinct
areas or may be distributed over the whole bottom side. The design of the direct illumination
lighting element 4 depends on the desired purpose, e.g. whether a desk is to be illuminated
for computer work or e.g. a larger conference room is to be illuminated for a meeting.
[0031] Further, an indirect illumination lighting element 5 is positioned on the top side
3 of the lighting unit 1. The indirect illumination lighting element 5 may be positioned
at one or various distinct positions or be distributed over the whole top side. The
design of the indirect illumination lighting element depends on the desired illumination,
e.g. brightness, the size and also the form of the interior. The latter influences
the way the light is reflected. Therefore according to an advantageous embodiment
at least the indirect illumination lighting element 5 is formed such, that a major
part of the emitted light hits the ceiling of side walls in a predetermined angle,
preferably perpendicularly.
[0032] Further, a connection element 6 is provided for establishing a connection between
the lighting unit 1 and a control unit 7. The connection element is preferably a wireless
sending and transmitting unit or a wired connection.
[0033] According to a further advantageous embodiment the connection element 6 provides
a connection to the control unit 7 of another lighting unit 1 or a central control
unit.
[0034] The wireless transmission unit is a transmission unit which works in the regime around
2.4 GHz and uses an encryption of at least 8 bit. Alternatively, other frequency bands
are used which are suitable in respect to range, interferences, allowed frequency
bands and radiation exposure.
[0035] Further, the lighting unit comprises a not shown electrical circuit for driving the
LEDs or groups of LEDs. This circuit is designed to run alternatively on either DC
or AC power. In case of AC power input the circuit includes an AC-DC converter following
by a a constant current source which can comprise an electronic component for controlling
the operating current of a LED or a group of LEDs by using a signal with bit angle
modulation other than the pulse width modulation. This signal is e.g. the internal
control signal. In case of DC power input the AC-DC converter will be by-passed, This
enables the light units to be able to use both DC and AC power for example by using
solar and/or wind power in parallel to the generally AC network.
[0036] It is possible that AC power is not needed at all when lighting units are planned
to run on DC power networks. In this case there will be no need for the AC-DC converter.
The solar or wind power plant may be positioned at the outside of the interior, e.g.
a roof.
[0037] When using bit angle modulation, the LED is driven by a pulse train that is the binary
word defining the value of a required intensity. Each bit of the pulse train is stretched
by a ratio defined by the binary significance of each bit. Each bit of the binary
word is effectively allocated a fixed range of phase angles within the drive cycle.
The advantage of bit angle modulation is a simple implementation, and, as the drive
signal is a multiple of the modulation frequency, a reducing of potential flicker.
Also, because the LED drive signal contains a digital code of the intensity value,
other devices may recover the data.
[0038] According to an advantageous embodiment a bit angle modulated internal control signal
is provided to one or more electrical circuits which provides in response thereon
a driving current to one or more Lends.
[0039] The control unit 7 provides internal control signals 14 to a warm light LED unit
8 and a cold light LED unit 9 or the at least one electrical circuit for providing
their driving current. The control unit is, as depicted in Figure 1, positioned within
the housing 13 of the lighting unit. 1. The connection element 6 provides then a wired
connection to the control unit 7.
[0040] Alternatively, the control unit 7 is positioned at the fixing point 18, where the
lighting unit 1 is suspended at the ceiling. In this case, the connection element
6 may either provide a wired connection to the control unit 7 or transmit a signal
to the control unit 7 wirelessly.
[0041] According to another embodiment, the control unit 7 is positioned at a predetermined
position inside or outside the exterior. This allows a control of illumination e.g.
from a central position for several rooms.
[0042] The warm light LED unit 8 comprises at least one LED providing a warm light, preferably
corresponding to a temperature range between about 1500 and about 3500 Kelvin. Further,
the direct illumination lighting element 4 comprises a cold light LED unit 9 with
at least one LED providing cold light that is preferably in a temperature range above
about 3500 Kelvin.
[0043] According to an embodiment, the warm light LED unit 8 comprises at least one blue
LED, which is covered with a coloured element having a colour in the orange or red
range. For the cold light LED unit 9 at least one blue LED is used, which is covered
with a coloured element in the yellow range.
[0044] Alternatively, other luminescent material is used to cover an LED which can excite
the luminescent material.
[0045] On the top side a first LED 10 is positioned as a part of the indirect illumination
lighting element, closely together with at least a second LED 16. Therefore preferably
an array of at least two LEDs with colours is formed such that white light can be
produced. This may be a combination of a red, green and blue LED or a combination
of a blue and yellow LED. By the use of a combination of a red, green and blue LED,
different colours can be produced dependent on the situation for which the illumination
is desired.
[0046] In addition, an amber coloured LED 11, possibly as a part of a multicolour LED 10,
is positioned on the top side. As amber is the predominant colour of the human skin,
by using amber, that is a colour between yellow and orange, the room illumination
may be defined as comfortable and showing the people in an approximately natural light.
[0047] The LEDs of the warm light LED unit 8, the cold light LED unit 9, the first LED 10
and the amber LED 11 may be put into separate glass, plastic or other transparent
housings. This allows to use cheap custom LEDs, so that the whole lighting unit 1
can be produced cheaply.
[0048] Alternatively, two or more LEDs may be put into a common housing, so that so called
multicolour LEDs are formed. Thus, the various LED chips are contained in one component
so that on the one hand less space is needed on a printed circuit board, and on the
other hand a very good mixing of various colours can be achieved. Particularly a red,
green and blue LED may be contained in a common housing.
[0049] Additionally, a movement detector 12 may be installed on the bottom side 2 of the
lighting unit 1, If a movement is determined within the sensitive area of the movement
detector, e.g. a predetermined cone extending from the lighting unit 1, a movement
detector signal 15 is provided to the control unit 7 via the connection element 6
or directly.
[0050] An internal control signal 14 for controlling the brightness of the illumination
provided by the lighting unit may be sent either via the connection element 6 or directly
to at least one or all of the following, the warm light LED unit 8, cold light LED
unit 9, first LED 10 and amber LED 11. Thus, a desired brightness and colour of the
illumination can be achieved.
[0051] The first LED 10 may therefore comprise at least a second LED 16,e.g. in that the
at least first LED 10 is formed by an LED group or array comprising several LEDs.
Particularly, the first LED 10 is a blue LED and the second LED is a yellow LED. Alternatively
me at least first LED 10 and at least second LED 16 may be formed by a group of at
least one red, green and blue LED. Further, the above set-ups with blue and yellow
LEDs and red, green and blue LED may be used both for the indirect illumination unit,
e.g. alternating. Thus the lighting unit can be optimised in regard to its Unction,
e.g. achievable brightness, colours, life time etc, and costs.
[0052] In Figure 2 a lighting network 20 is depicted which comprises several lighting units
1, The control unit 7 is positioned either inside of the housing 13 of a lighting
unit 1, at the fixing point 18 of a lighting unit 1 or at a position in between, e.g.
along the cable for providing electrical power to the lighting unit.
[0053] An external control signal 23 for setting the light to a required value for a predetermined
scenario, such as meeting, press conference, presentation, computer work, or cleaning
the computer, is transmitted from a master control unit 21 to each lighting unit 1,
e.g. to the connection unit 6, where it is received and further transferred to the
control unit 7. Thus, the light intensity of each lighting unit 1 can be adapted to
the required value.
[0054] The master control unit may be a mobile remote control unit or fixed at a certain
position, e.g. at a wall of the interior, or being realised by e.g, a web server which
accesses one or more lighting units e.g. via the internet as access network. Alternatively,
a fixed or mobile master control unit may be accessed via the internet by a web server,
[0055] The external control signal 23 may therefore contain information on the brightness
or light intensity of each LED or group of According to an embodiment this is realised
by prescribing the driving current for a LED or group of LEDs. Alternatively or additionally
the external control signal may contain information on the brightness or light intensity
or colour direct lighting element 4 or indirect lighting element 5. The control unit
7 of each lighting unit may then assign the individual values for a LED or group of
LEDs.
[0056] The transmission of the external control signal 23 can be either performed in a wired
or a wireless mode. The master control unit 21 may be positioned at a central position
inside the interior, e.g. given at a switch unit positioned at an entry or at a switch
unit also used for other purposes such as teleconference etc., or outside, e.g. at
a control room.
[0057] An overall control signal 22, defining the light situation, such as a press conference,
discussion, meeting, presentation, computer work or cleaning, is provided as the overall
control signal 22 to the master control unit 21 which then splits the information
such that each lamp or lighting unit adapts the required intensity and colour such
that as a whole, in the interior, the desired lighting situation is created. This
overall control signal may be provided by a control program, user input or e.g. by
a web server or other remote control entity, e.g. by using a transmission over the
internet.
[0058] Further in the master control unit 21 the external control signal 23 may be created
on basis of the overall control signal 22. Therefore, the master control unit may
use also further information, such as time or already existing brightness, e.g. due
to sunshine, in the room to be illuminated. Alternatively or additionally the master
control unit may use movement information as set out below:
The master control unit 21 or/and at least one of the lighting units 1 is connected
to the movement detector 12. The movement detector signal 15, see Figure 3, may be
combined in the master control unit 21 in order to adapt the external control signal
23.
[0059] Alternatively, the movement detector signal 15 may be combined in a lighting unit
1 with the internal control signal 14 such that the intensity or/and colour of the
illumination is changed when a person 24 enters the detection cone 25 of a movement
detector 12 positioned in or at a lighting unit 1.
[0060] Alternatively or additionally, a movement detector 12 in the master control unit
21 may provide a movement detector signal 15 if a person enters the predetermined
range defined by the movement detector 12 and, thus, modify the external control signal
23 such that e.g. all lighting units 1 are switched on, or switched from a power safe
mode, where the light is completely switched off or remains at a certain dimming level,
to a full illumination mode or a brighter dimming level, e.g. when a person enters
a room.
[0061] Thus the lighting units 7 or control entities in a network 20 of lighting units 1
include additional optional intelligence based on movement sensors which may be used
to evaluate the real required light intensity.
[0062] In Figure 4 another embodiment of the lighting unit 1 is depicted which is also formed
as a suspended lamp. In Figure 5 a cross section of the embodiment of the lighting
unit 1 depicted in Figure 4 is shown. A top side PCB (printed circuit board 50) is
arranged within a top side reflector element 51. On the top side PCB 50 the LED or
LED arrays forming the indirect illumination lighting element 5 are placed. At the
bottom side 2 a bottom side PCB 52 is placed within a bottom side reflector element
53. Further, protection elements 54 are provided, which can additionally be used for
defusing the light of the LEDs.
[0063] At the bottom side 2 further a movement detector 12 is placed, preferably inside
the bottom side reflector element 53. Thus the detecting cone of the movement detector
12 can basically coincide with the lighting cone of the direct illumination element.
[0064] The movement detector 12 detects a movement and provides this information as movement
detector signal 15 to the control unit 7. The control unit 7 provides an internal
control signal 14 to the individual or group of LEDs placed on the PCB boards, see
also Figure 1. This can be realised by providing the internal control signal to an
electrical circuit externally or internally in regard to the LED or group of LEDs
or LED unit. The electrical circuit then provides a corresponding driving current
or driving voltage to the LED or group of LEDs or LED unit, The control unit 7 can
be formed by separated sub units, e.g. of which one controls the direct illumination
element 4, the other one the indirect illumination element 5.
[0065] Also in this embodiment the direct illumination lighting element 4 comprises a protection
element 54, a warm light LED unit 8 and a cold light LED unit 9 placed on a bottom
side PCB board 52.
[0066] The indirect illumination lighting element 5 comprises a protection element 54, a
multicolour first LED 10 placed on a top side PCB 50 and a top side reflector element
51.
[0067] The connection element 6 is placed on a position where a good reception of external
signals is ensured and short transmission paths to the control unit 7 can be ensured.
[0068] In Figure 6 the bottom side PCB 52 is depicted, In an alternating manner, warm light
LED units 8 and cold light LED units 9 comprising each at least one LED are arranged
on the bottom side PCB 52. Thus, a desired overall colour of light from the direct
illumination lighting element 4 can be achieved.
[0069] Alternatively the arrangement of the LED units may be differently, e.g. areas on
which predominantly warm light LED units 8 arranged and those with predominantly cold
light LED units 9,
[0070] The bottom side PCB board 52 may comprise several individual PCB boards, which are
connected to each other.
[0071] For connecting the individual PCBs with each other a PCB connector 55 is provided
at an end of an individual PCB board. Further a cable connector 56 is provided for
establishing electrical connections between the individual PCB boards or to a component
outside the PCB board. Preferably, the electrical connection between the individual
PCB boards is established by the PCB connector 55, too, so that at least a part of
the cable connector 56 is integrated in a PCB connector 55.
[0072] In Figure 7 the top side PCB 50 is depicted. Each of the first LEDs 10 is a LED combination
of a red, green and blue LED. Added to this combination is an amber colored LED 11,
either separately or within the same housing, These LED groups are arranged turned
in respect to each other in order to achieve a more conform illumination of the interior
with a common mixed colour. Again, the top side PCB 50 may comprise several elements,
which are connected to each other by PCB connectors 55.
[0073] A security device 57 is provided in order to compensate a failure of one or more
LED's in order to keep the lighting unit in function, when one or more of the LED
is broken. Further, an array of resistors 58 is provided to adapt the top side PCB
50 or/and the bottom side PCB 51 for a position in the left side, the middle left
side, the middle right side or the right side of the lighting unit. Holes 59 are provided
to fix a PCB with screws or rivets in the lighting unit.
List of reference numbers
[0074]
- 1
- lighting unit
- 2
- bottom side
- 3
- top side
- 4
- direct illumination lighting element
- 5
- indirect illumination lighting element
- 6
- connection element
- 7
- control unit
- 8
- warm light LED unit
- 9
- cold light LED unit
- 10
- multicolour LED (red, green, blue)
- 11
- amber LED
- 12
- movement detector
- 13
- housing
- 14
- internal control signal
- 15
- movement detector signal
- 16
- second LED
- 17
- vertical
- 18
- fixing point
- 20
- lighting network
- 21
- master control unit
- 22
- overall control signal
- 23
- external control signal
- 24
- person
- 25
- detection cone
- 50
- top side PCB
- 51
- top side reflector element
- 52
- bottom side PCB
- 53
- bottom side reflector element
- 54
- protection elements
- 55
- PCB connector
- 56
- cable conn ector
- 57
- security device
- 58
- array of resistors
- 59
- holes
1. Lighting unit (1) for illuminating an interior comprising
- a housing (13) with a bottom side (2) and a top side (3);
- a direct illumination lighting element (4) arranged at the bottom side (2) with
at least one warm light LED unit (8) providing white light with a first colour temperature
and at least one cold light LED unit (9) providing white light with a second colour
temperature;
- an indirect illumination lighting element (5) arranged at the top side (3) comprising
at least a first LED (10) and a second LED (16) having different colours and at least
one amber coloured LED (11);
- a connection element (6) for connecting the lighting unit (1) to a control unit
(7).
2. Lighting unit (1) according to claim 1, further comprising a control unit (7) for
controlling the light intensity of the lighting unit (1).
3. Lighting unit (1) according to claim 2 wherein the control unit (7) is adapted such
that for controlling the light intensity of the lighting unit (1) an internal control
signal (14) is provided for setting the light intensity of at least one of direct
illumination element (4), warm light LED unit (8), cold light LED unit (9), indirect
illumination element (5), first LED (10), second LED (16) and amber LED (11).
4. Lighting unit (1) according to any of the previous claims wherein the connection element
(6) is a transmission interface for wireless transmission.
5. Lighting unit (1) according to any of the previous claims wherein the connection element.
(6) is a transmission interface for wired transmission, particularly for a connection
to a DALI bus system,
6. Lighting unit (1) according to any of the previous claims further comprising a movement
detector (12) for detecting a movement within a predetermined range of the lighting
unit (1) which provides a movement detector signal (15) to the connection element
(6),
7. Lighting unit (1) according to any of the previous claims, wherein the lighting unit
(1) is fixed at a certain position, particularly as a suspended lamp.
8. Lighting unit (1) according to claim 7, wherein the control unit (7) is positioned
inside or outside the housing (13),
9. Lighting network (20) comprising at least two lighting units (1) according to any
of the previous claims and a master control unit (21) for providing an external control
signal (23) to at least one of the control units (7).
10. Method for lighting an interior using at least one lighting unit (1) according to
any of the claims 2 to 8 or a lighting network (20) according to claim 9 comprising
the following steps
- providing an external control signal (23) to the control unit (7);
- providing the internal control signal (14) from the control unit (7) to the direct
illumination lighting element (4) and/or the indirect illumination lighting element
(5);
- setting a light intensity and a light temperature for the direct illumination lighting
element (4) on the basis of the internal control signal (14);
- setting the colour of the indirect illumination lighting element (5) by adjusting
the intensity of at least one of first LED (10) and second LED (16) and by adjusting
the intensity of the amber LED (11),
11. Method according to claims 9 and 10, comprising the further steps:
- providing an overall control signal (22) containing information on a lighting scenario;
- creating an external control signal (23) in the master control unit (21) on basis
of said overall control signal (22).
12. Method according to any of the previous claims 10 or 11 comprising the further steps:
- receiving a movement detector signal (15);
- creating an internal control signal (14) or an external control signal (23) using
the movement detector signal