[0001] Navigational lighting systems in many locations are not easily accessible, must operate
with high reliability in order to provide safety, and be autonomously powered. -The
electrical power, which is generally batteries, and the lamps are conserved by operating
only at night, and are turned off in the daytime by light sensors.
[0002] In order to avoid possible ambiguity to mariners, it is desirable to have all lanterns
marking a channel, hazard, or structure to light or flash at the same time at dusk,
and to extinguish simultaneously at dawn. This is difficult to accomplish by independent
light sensing devices connected to each of the lanterns because (1). abvailable light
sensors are difficult to calibrate, compensate, and do not track each other well,
(2) in extreme northern and southern latitudes, the transition from night to day may
be quite slow, thereby causing lanterns only slightly out of calibration to light
and extinguish far apart from each other in time, and (3) shading of the light sensor
by other structurs causes orientation sensitivity and sensitivity to the sun angle.
[0003] Prior art document US-A 4 132 983 discloses a warning light system constructed of
an array of flashable, warning lights. The warning lights are self-contained, battery
powered warning lights that may be arranged in an array and controlled to flash simultaneously.
Each warning light includes individual transceiving means for transmitting a coded,
radio frequency signal to each other light of an array and a receiving radio frequency
signal from each other light of the array to cause each lamp of each light to flash
on and off in synchronism. Each light has a built- in transceiving antenna arranged
within the light lens assembly and completely housed therein.
[0004] In prior art document US-A 3 781 853, a navigational light system is disclosed In
which all of the lan- tems flash in unison and are actuated by a synchronizing signal
initiated by the first lantern to be actuated. That system synchronized all of the
navigational lights and insured that in the event one of the lanterns failed, the
remainder of the lanterns would operate.
[0005] However, the present systems utilize a single light mesuring threshold point at the
output of the light sensors to define the boundary between day and night. If the output
of the sensor is above the threshold (day condition), flashing of the lantern is inhibited,
and if below the threshold (night conditions), flashing is enabled. All of the lanterns
send synchronizing pulses at the beginning of each flash code sequence to all of the
lanterns to actuate all of the lanterns that are not inhibited.
[0006] It is an object of the present invention to provide an improved system and method
for synchronizing a plurality of navigational lanterns by compensating for the fact
that the independent light sensors connected to each of the lanterns respond differently
to the light levels as well as allow the system to operate even in the event of a
light level sensor failure.
[0007] The present invention provides a system and a method as defined in claims 1 and 7
to solve this object.
[0008] The navigational lanterns are each equipped with an idependent light level sensing
means and each sensing means measures the thresholds between day, twilight and night.
When a sensor is measuring day, its connected lantern is disabled from flashing and
the connected lantern is disabled from providing a synronising signal to the other
lanterns. When a sensor measures twilight, the connected lantern is enabled, so as
to flash if a synchronization signal is received from other lanterns, but is disabled
from providing a synchronizing signal to other lanterns. And if a sensor measures
night, the connected lantern is enabled and provides a synchronizing signal to operate
itself and the other lanterns.
[0009] In a first embodiment of the present invention the navigational lantern system has
a plurality of navigational lanterns in which each lantern includes means for providing
a synchronizing signal to actuate a lantern and each lantern includes a synchronizing
terminal and the input and output from each lantern is connected to the synchronizing
terminal of the other lanterns in the system and in which each lantern has an improved
light level sensing means. Each light level sensing means senses the thresholds of
day, twilight and night. Means are connected to each sensing means, when the sensing
means senses day, for disabling the connected lantern and disabling the means for
providing a synchronizing signal from the connected lantern. Means are also connected
to the sensing means, when the sensing means senses twilight, enabling the connected
lantern to receive a synchronizing signal, but disabling the means for providing a
synchronizing signal from the connected lantern. And means are connected to each sensing
means, when the sensing means senses night, enabling the connected lantern for lighting
and enables the means for providing a synchronizing signal from the connected lantern
to the other lanterns.
[0010] In a second embodiment of the present invention the sensing means includes a photo-detector
having a resistance which varies inversely proportional to the light intensity. Means
are connected to the photodetector transmitting electric current thereto and means
are connected to the photodetector for measuring three different levels of light illuminating
the photodetector.
[0011] The method of synchronizing a plurality of navigational lanterns at dawn and dusk
includes sensing at each of the lanterns the levels of day, twilight and night, when
each of the lanterns senses day, disabling the day sensing lantern, and when each
of the lanterns senses twilight, enabling the lantern to flash but only if the lantern
receives a synchronization signal from another lantern. And each of the lanterns when
it senses night, enables and flashes the lantern and also sends the synchronization
signal to the other lanterns to flash.
[0012] Other and further objects, features and advantages will be apparent from the following
description of the presently preferred embodiment of the invention, given for the
purpose of disclosure and taken in conjunction with the accompanying drawings, in
which:
Figure 1 is a truth table indicating the response of a sensor to various levels of
surrounding illumination,
Figure 2 is a chart illustrating desperation of a plurality of lanterns utilizing
light level sensors which respond differently to the light level,
Figure 3 is a graph illustrating the response of a plurality of lanterns having independent
light sensors with varying responses in which one of the light sensors has failed
in a mode indicating a day condition,
Figure 4 is a graph illustrating the response of a plurality of navigational lanterns
having independent light sensors with varying responses in which one of the light
sensors has failed in a mode continuously indicating a night condition,
Figure 5 is an electrical schematic diagram illustrating one type of structure for
implementing the present invention, and
Figure 6 is an electrical schematic diagram illustrating another structure for implementing
the present invention.
[0013] Referring now to document US-A 3 781 853 which is incorporated herein by reference,
a portion of a navigational light system is shown in which all of the lanterns are
connected together to a synchronizing terminal to aid the lanterns to flash in unison.
Each lantern is independent and is equipped with an independent light-sensing means
such as the daylight control. In that system, a single threshold point at the output
of the light sensor defines the boundary between night and day. In that system, if
the output of the light level sensing means is above the threshold (day condition)
then flashing of the lanterns is inhibited. If the output is below the threshold (night
condition) flashing is enabled and also the connected lantern sends a synchronizing
pulse to flash the other lanterns if their light level sensors are sensing night.
As has been indicated above, it is difficult to calibrate all of the independent light
sensors to simultaneously detect the threshold between day and night. Therefore, it
is difficult to obtain the simultaneous operation of all of the lanterns in the system
to light at the same time at dusk and to extinguish simultaneously at dawn.
[0014] In the present method and system, two thresholds are established, defining each of
the sensors' output into three regions referred to a night, twilight and day. Each
lantern flashes at night when its sensor detects night and is extinguished during
the day if its light sensor senses daylight. However, when a sensor's output falls
between the two thresholds (twilight), a lantern will be enabled so that it will flash
only if a synchronizing pulse is received. A lantern measuring the twilight condition
will not send synchronizing pulses to the other lanterns. The spacing between the
two thresholds is selected to establish the desired width of the twilight region and
is preferably set slightly wider than the spread of the individual sensor outputs
of the individual lanterns caused by the factors which create a difference in response
between the individual light sensors. As previously indicated, the difference is caused
by (1) the individual light sensors are difficult to calibrate, compensate and do
not track each other well, (2) in extreme northern and southern latitudes, the transition
from night to day may be quite slow causing the sensor's response to be apart from
each other in time, and (3) shading of one or more sensors by other structures causes
changes in the sensor output due to orientation sensitivity and sensitivity to sun
angles.
[0015] In order to accomplish the method and function of the present invention, as best
seen in Figure 1, a truth table, generally indicated by the reference numeral 10 indicates
the output or response of each individual light level sensor to the measured condition
of day 12, twilight 14, and night 16. That is, the output or response to the light
level sensor when it measures day is the response 18 which indicates that the connected
lantern never flashes or sends a synchronizing signal. In response to a measurement
of the twilight 14, the output of the measuring light level sensor is 20 which indicates
that the lantern is enabled to flash but only when a synchronizing signal is received
from other lanterns and the lantern is inhibited from sending a synchronizing signal
to the other lanterns. And as indicated in response block 22, when the light level
sensor senses night 16, the connected lantern will be enabled, will flash, and will
send a synchronizing signal to the other lanterns so that they will simultaneously
flash if they are not inhibited.
[0016] Referring now to Fig. 2, a plurality of lanterns, such as four for illustration only,
are connected in a navigational system and are designated as lantern 1, lantern 2,
lantern 3 and lantern 4. Each of the lanterns has an independent light level sensor
suitable for measuring light intensities corresponding to day 24, twilight 26 and
night 28. A twilight 26 output can be either dawn or dusk. For purposes of illustration,
the individual light level sensors output for each of the individual lanterns is indicated
by an arrow. Thus, the sensor of lantern 1 has an output 30 indicating that the sensor
of lantern 1 is measuring a twilight light intensity. The sensor of lantern 2 as indicated
by arrow 32 is measuring a night light level. The sensor of lantern 3 as indicated
by the arrow 34 is measuring twilight and the sensor of lantern 4 as indicated by
the arrow 36 is measuring a twilight light level. Under the conditions indicated in
Figure 2, assuming the light is going from dusk to night and referring to the truth
table in Figure 1, the sensor levels 30, 34 and 36 are all in the twilight zone whereby
the sensors of lanterns 1, 3 and 4 are enabled to flash, but only if a synchronizing
signal is received from another lantern and lanterns 1, 2 and 4 will not send synchronizing
signals. However, since the sensor of lantern 2 has a level 32 in the night zone,
lantern 2 will flash, and will send synchronizing signals to lanterns 1, 3 and 4.
Therefore, all of the lanterns will flash in synchronism because of the sensor level
32 of lantern 2. As night continues to fall, the sensors of lanterns 1, 3 and 4 will
eventually measure a night level 28 and therefore all of the lanterns will send a
synchronizing signal and the first synchronizing signal will cause all of the lanterns
to flash in unison.
[0017] On the other hand, assuming that the navigational light system of Figure 2 is moving
from a night condition to a day condition, all of the lanterns 1, 2, 3 and 4 would
flash in synchronism until the last sensor, the sensor of lantern 2, moves out of
the night 28 condition into the twilight 26 condition at which time all of the lanterns
would be extinguished as no synchronization pulses would be generated.
[0018] It is desirable that the width of the measured twilight region 26 be set slightly
wider than the spread of the individual sensor outputs 30, 32, 34 and 36 so that one
sensor output will not be measuring night while another is measuring day. If the width
of the region 26 is wider than the individual sensor outputs, then the system will
always operate in unison.
[0019] It is also important that the system be constructed and operated so that a failure
in one or more of the level light sensors does not unduly affect the operation of
the system.
[0020] Referring now to Figure 3, the operation of which is similar to that in Figure 2
with the exception that lantern 4 has a sensor which has failed and has a level 36a
giving an erroneous "day" indication at all times. Again, the operation of the system
in Figure 3 is the same as the operation of the system in Figure 2 with the exception
that lantern 4 remains off at all times. Again, the system will flash and light lanterns
1, 2 and 3 when the light level sensor of lantern 2 detects a level 32 in the night
zone 28. And on changing from night to day when the last sensor here, the sensor of
lantern 2 moves out of the night zone 28 all of the lanterns 1, 2 and 3 will extinguish
as there will be no synchronization pulses from any of the sensors.
[0021] Referring now to Figure 4, a system is shown in which the sensor of lantern No. 4
has failed and has an output reading of 36b at all times to give an erroneous "night"
reading. A failure of this type causes all of the lanterns 1, 2 and 3 to begin flashing
as soon as its independent sensor output crosses from the day zone 24 to the twilight
zone 26. Thus, under the sensor levels indicated in Figure 4, lanterns 1 and 2 would
be flashing due to the synchronous signals sent out by the sensor of lantern 4 but
since the sensor of lantern 3 has a level 34 still in the daylight zone 24, then lantern
3 would not be simultaneously flashing with the other lanterns. Similarly, assuming
that night is turning into day, the lanterns 1, 2 and 3 would continue to flash until
their sensors sense the daylight zone 24 in which case they would be extinguished.
Therefore a failure of the type shown in Figure 4 will cause the simultaneously on/off
feature not to function, but it will not be any more disadvantageous than the present-day
systems.
[0022] There are various possible implementations of the method and operation previously
described.
[0023] Referring now to Figure 5, one type of structure is best seen having a flasher 40
such as one sold under the trademark SYNCHROSTAT by Tideland Signal Corporation for
flashing a conventional navigational light 42. The flasher 40 includes and enable
input port 44 for allowing operation of the flasher 40 or inhibiting the operation
of the flasher 40. The flasher 40 also includes a synchronous input port 45 which
is connected to a system synchronous line or terminal 46 to the remainder of the lanterns
in the system for receiving an actuating pulse from other lanterns or from the flasher
40. That is the flasher 40 also includes a synchronous output 48 which is connected
to the input of an NAND gate 50 for providing a synchronous signal which is transmitted
both to the synchronous terminal 46 and to the input port 45 of the flasher 40.
[0024] A light level sensing means is generally indicated by the reference numeral 52 and
includes a photo- detector 54 which is a variable resistance device in which the resistance
is inversely proportional to the incident light intensity. An electrical current source
56 supplies current through the photodetector to cause a voltage to appear at node
60 according to the IR drop across the current source 56. Resistors R1, R2 and R3
form a voltage divider establishing fixed voltages at nodes 62, and 63. During the
"daylight" hours, the voltage at node 60 is lower than the voltage at nodes 62 and
64. This daylight condition causes the voltage comparators 66 and 68 to produce a
logic low voltage at nodes 70 and 72, respectively. The logic low of node 72 is applied
to the enable port 44 of the flasher 40 causing the flasher 40 to remain inactive.
[0025] As day changes toward night, the resistance of the photodetector 5 increases and
the voltage at node 60 eventually exceeds the voltage at node 64 which causes the
comparator 68 to change state thereby driving node 72 to HIGH. This is the twilight
condition. A logic HIGH at the enable port 44 of the flasher 40 will cause the flasher
40 to initiate a flash code sequence upon receipt of a synchronization pulse on the
synchronous port 45. Therefore, if another lantern in the system provides a synchronization
signal to terminal 46, the lantern in the twilight condition will flash. However,
any synchronous output from the port 48 is not gated through NAND gate 50 to the terminal
46.
[0026] When the night condition is measured by the photodetector 54, its resistance is high
enough to drive the voltage at node 60 above that at node 62. This causes voltage
comparetor 66 to change state, thereby driving node 70 to HIGH. This, in turn, gates
a sync out signal from port 48 through the NAND gate 50 to the sync terminal 46 for
transmission to the other lanterns.
[0027] Another implementation of the invention is best seen in Figure 6 having a photodetector
54a connected to a current source 56a to provide a voltage output at node 60a which
is proportional to the light intensity encountered by the photodetector 54a. The voltage
at node 60a is transmitted through an analog to digital converter 80 to provide a
digital signal which is transmitted over a computer ad- dress/data buss 82 to a microprocessor
84 which is connected to a memory 86. The microprocessor 84 compares the digital representation
of the allumina- . tion level measured by the photodetector 54a relative to the daylight,
twilight and night thresholds stored in the memory 86. The truth table shown in Figure
2 is implemented in the microprocessor 84 and memory 86 to inhibit the switch 88 in
the event of a daylight signal, to enable the switch 88 in the event of a twilight
signal and to send out a synchronous pulse signal from the output 90 to the synchronizing
terminal 46a and to receive pulses on the input port 92.
[0028] The present invention, therefore, is well adapted to carry out the objects and attain
the ends and advantages mentioned as well as other inherent therein.
1. A navigational lantern system having a plurality of navigational lanterns (42,
42a), each lantern including means (44) for sending and receiving a synchronizing
signal to and from other lanterns, characterized in that a light level sensing means
(54, 54a) sensing the thresholds of day, twilight, and night, is connected to each
lantern (42, 42a), wherein each of said light level sensing means comprises a device
(52, 88) connected to each sensing means, and each device:
- when the connected sensing means (54, 54a) senses day, disables the connected lantern
(42, 42a) and its means for sending a synchronizing signal,
- when the connected sensing means (54, 54a) senses twilight, enables the connected
lantern (42, 42a) to receive a synchronizing signal, but disables the connected lantern's
means (44) from sending a synchronizing signal, and
- when the connected sensing means (54, 54a) senses night, enables the connected lantern
(42, 42a) and enables the connected lantern's means (44) for sending a synchronizing
signal.
2. The system according to claim 1, characterized in that said device is formed by
switch means (88).
3. The system according to claim 1 or 2, characterized in that the sensing means (54,
54a) includes:
a photodetector (54, 54a) having a resistance which varies inversely proportional
to the light intensity, and
means (52) connected to the photodetector (54, 54a) for measuring the three different
levels of light illumination on the photodetector (54, 54a).
4. The system according to anyone of claims 1 to 3, characterized in that the width
of the twilight measurement is wide enough to preclude one sensor output measuring
night while another sensor output is measuring day.
5. The system according to claim 1 or 4 characterized in that each lantern (42, 42a)
includes a synchronizing terminal for actuating the lantern, and that the input and
output from each lantern is connected to the synchronizing terminal of the other lanterns.
6. The system according to claim 5, characterized in that the width of the twilight
measurement is greater than the spread of the outputs of the individual light level
sensing means (54, 54a).
7. A method of synchronizing a plurality of navigational lanterns (42, 42a) at dawn
and dusk comprising steps of:
- sensing at each of the lanterns (42, 42a) the levels of day, twilight, and night,
and
-disabling, when a lantern (42, 42a) senses day, characterized by the further comprising
steps of:
- enabling, when a lantern (42, 42a) senses twilight, the lantern (42, 42a) to flash
but only if the lantern (42, 42a) receives a synchronization signal from another lantern,
and
- enabling and flashing, when the lantern (42, 42a) senses night, the lantern and
sending a synchronization signal to the other lanterns to flash.
8. The method of claim 7, characterized in that sensing the levels of day and night
is performed such that while one lantern (42, 42a) senses day, another lantern will
not measure night.
1. Un système de feux de signalisation pour la navigation, comportant une pluralité
de feux de signalisation (42, 42a) pour la navigation, chaque feu de signalisation
comportant des moyens (44) pour émettre et recevoir un signal de synchronisation de
et à partir d'autres feux de signalisation, caractérisé en ce que des moyens (54,
54a) de détection de niveau de lumière, détectant les seuils de jour, de crépuscule
et de nuit, sont reliés à chaque feu de signalisation (42, 42a), chacun desdits moyens
de détection de niveau de lumière comportant un dispositif (52, 88) relié à chacun
des moyens de détection, et chaque dispositif:
- met hors circuit le feu de signalisation relié (42, 42a) et ses moyens pour émettre
un signal de synchronisation, lorsque les moyens de détection reliés (54, 54a) détectent
le jour,
- met en circuit le feu de signalisation relié (42, 42a) pour recevoir un signal de
synchronisation, mais met hors circuit les moyens (44) du feu de signalisation reliés
pour empêcher que celui-ci émette un signal de synchronisation, lorsque les moyens
de détection reliés (54, 54a) détectent le crépuscule, et
- met en circuit le feu de signalisation relié (42, 42a) et met en circuit les moyens
(44) du feu de signalisation relié pour l'émission d'un signal de synchronisation
lorsque les moyens de détection reliés (54, 54a) détectent la nuit.
2. Le système selon la revendication 1, caractérisé en ce que ledit dispositif est
formé par des moyens de commutation (88).
3. Le système selon la revendication 1 ou 2, caractérisé en ce que les moyens de détection
(54, 54a) comportent:
un photodétecteur (54, 54a) présentant une réi- sistance qui varie de façon inversement
proportionnelle avec l'intensité de la lumière, et des moyens (52) reliés au photodétecteur
(54, 54a) pour mesurer les trois niveaux différents d'éclairement par la lumière sur
le photodétecteur (54, 54a).
4. Le système selon l'une quelconque des revendications 1 à 3, caractérisé en ce que
la largeur de la mesure de crépuscule est suffisamment importante pour empêcher qu'une
sortie de détecteur mesure la nuit tandis qu'une autre sortie de détecteur mesure
le jour.
5. Le système selon la revendication 1 ou 4, caractérisé en ce que chaque feu de signalisation
(42, 42a) comporte une borne de synchronisation pour actionner le feu de signalisation,
et en ce que l'entrée et la sortie de chaque feu de signalisation sont reliées à la
borne de synchronisation des autres feux de signalisation.
6. Le système selon la revendication 5, caractérisé en ce que la largeur de la mesure
du crépuscule est supérieure à la largeur des sorties des moyens individuels de détection
de niveau de lumière (54, 54a).
7. Un procédé pour synchroniser une pluralité de feux de signalisation (42, 42a) pour
la navigation, à l'aube et au crépuscule, comportant les phases consistant à:
- détecter à chacun des feux de signalisation (42, 42a) les niveaux de jour, de crépuscule
et de nuit, et
- mettre hors circuit un feu de signalisation (42, 42a) lorsqu'il détecte le jour,
caractérisé par les phases supplémentaires consistant à:
- lorsqu'un feu de signalisation (42, 42a) détecte le crépuscule, mettre en circuit
le feu de signalisation (42, 42a) pour qu'il éclaire seulement si le feu de signalisation
(42, 42a) reçoit un signal de synchronisation provenant d'un autre feu de signalisation,
et
- lorsque le feu (42, 42a) détecte la nuit, mettre en circuit et faire éclairer le
feu de signalisation et envoyer un signal de synchronisation vers les autres feux
de signalisation pour qu'ils éclairent.
8. Le procédé selon la revendication 7, caractérisé en ce que la détection des niveaux
de jour et de nuit est exécutée de telle manière que, lorsqu'un feu de signalisation
(42, 42a) détecte le jour, un autre feu de signalisation ne mesure pas la nuit.
1. Navigationslampensystem mit mehreren Navigationslampen (42, 42a), von denen jede
eine Einrichtung (44) zum Senden und Empfangen eines Synchronisiersignales zu und
von anderen Lampen hat, dadurch gekennzeichnet, daß eine Lichtpegelsensoreinrichtung
(54, 54a), die die Pegel von Tages-, Zwie- und Nachtlicht erfaßt, mit jeder Lampe
(42, 42a) verbunden ist, wobei jede Lichtpegelsensoreinrichtung eine Vorrichtung (52,
88) aufweist, die mit jeder Sensoreinrichtung verbunden ist, und jede Vorrichtung:
- wenn die verbundene Sensoreinrichtung (54, 54a) Tageslicht erfaßt, die verbundene
Lampe (42, 42a) und deren Einrichtung zum Senden eines Synchronisiersignates abschaltet,
- wenn die verbundene Sensoreinrichtung (54, 54a) Zwielicht erfaßt, die verbundene
Lampe (42, 42a) einschaltet, um ein Synchronisiersignal zum empfangen, jedoch die
Einrichtung der verbundenen Lampe vom Senden eines Synchronisiersignales abschaltet,
und
- wenn die verbundene Sensoreinrichtung (54, 54a) Nachtlicht erfaßt, die verbundene
Lampe (42, 42a) einschaltet und die Einrichtung der verbundenen Lampe zum Senden eines
Synchronisiersignales einschaltet.
2. System nach Anspruch 1, dadurch gekennzeichnet, daß die Vorrichtung durch eine
Schaltereinrichtung (88) gebildet ist.
3. System nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Sensoreinrichtung
(54, 54a) aufweist:
einen Photodetektor (54, 54a) mit einem Widerstandswert, der sich umgekehrt proportional
zur Lichtstärke ändert, und
eine Einrichtung (52), die mit dem Photodetektor (54, 54a) verbunden ist, um die drei
verschiedenen Pegel der Lichtbeleuchtung auf dem Photodetektor (54, 54a) zu messen.
4. System nach einem der Ansprüche 1 bis 3 dadurch gekennzeichnet, daß die Weite der
Zwielichtmessung weit genug ist, um ein Ausgangssignal eines Nachtlicht messenden
Sensors auszuschließen, während ein anderes Sensor-Ausgangssignal Tageslicht mißt.
5. System nach Anspruch 1 oder 4, dadurch gekennzeichnet, daß jede Lampe (42, 42a)
einen Synchronisieranschluß zum Betätigen der Lampe aufweist, und daß der Eingang
und Ausgang von jeder Lampe mit dem Synchronisieranschluß der anderen Lampen verbunden
ist.
6. System nach Anspruch 5, dadurch gekennzeichnet, daß die Weite der Zwielichtmessung
größer ist als die Streuung der Ausgangssignale der einzelnen Lichtpegelsensoreinrichtungen
(54, 54a).
7. Verfahren zum Synchronisieren einer Vielzahl von Navigationslampen (42, 42a) bei
Morgendämmerung und Abenddämmerung mit den folgenden Verfahrensschritten:
- Erfassen an jeder der Lampen (42, 42a) der Pegel von Tages-, Zwie- und Nachtlicht
und
- Abschalten, wenn eine Lampe (42, 42a) Tageslicht erfaßt,
gekennzeichnet durch die weiteren Verfahrensschritte von:
- wenn eine Lampe (42, 42a) Zwielicht erfaßt, Einschalten der Lampe (42, 42a) zum
Aufleuchten, jedoch nur, falls die Lampe (42, 42a) ein Synchronisationssignal von
einer anderen Lampe empfängt, und
- wenn die Lampe (42, 42a) Nachtlicht erfaßt, Einschalten und Aufleuchten der Lampe
und Senden eines Synchronisationssignales zu den anderen Lampen, um (diese) aufzuleuchten.
8. Verfahren nach Anspruch 7, dadurch gekennzeichnet, daß das Erfassen der Pegel von
Tages-und Nachtlicht derart durchgeführt wird, daß, während eine Lampe (42, 42a) Tageslicht
erfaßt, eine andere Lampe nicht Nachtlicht mißt.