VISUAL INFORMATION SYSTEMS

SYSTEMES D'INFORMATIONS VISUELLES

English Abstract

A visual information system includes an array (2) of light emitting elements
located at the side of a train track (4). The elements
are individually energisable by a controller (10) in response to a
predetermined program stored in a memory (12) and representative of a
predetermined visual image. The controller (10) causes selected elements to be
turned ON and OFF, some repetitively, in a predetermined
sequence as dictated by the program with a time span of 0.015 seconds. A
sensor (6) activates the controller (10) upon the approach
of a train so that a passenger gazing at the array (2) as the train passes
will perceive the said image apparently extending over an area
substantially greater than the area of said array (2).

French Abstract

Un système d'informations visuelles comporte un réseau (2) d'éléments électroluminescents disposé sur le côté d'une voie ferrée (4). Ces éléments peuvent être individuellement alimentés en énergie par un dispositif de commande (10) en réponse à un programme préétabli enregistré dans une mémoire (12) et ils sont représentatifs d'une image visuelle préétablie. Le dispositif de commande (10) permet d'allumer ou d'éteindre des éléments sélectionnés, certains de manière répétée, suivant une séquence préétablie dictée par le programme selon un intervalle de temps de 0,015 secondes. Un capteur (6) active le dispositif de commande (10) dès qu'un train approche de telle sorte qu'un passager fixant le réseau (2) alors que le train passe, perçoit ladite image comme s'étendant apparemment sur une aire sensiblement plus grande que l'aire dudit réseau (2).

Claims

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CLAIMS
1. A visual information system comprising an array
consisting of a plurality of individually and selectively
energisable light sources arranged in rows and columns, a
memory for storing a program representative of a
predetermined image, a controller actuatable to control
the selection and sequence of energisation of the light
sources within a predetermined time span in accordance
with the predetermined program stored on the memory so
that a viewer observing the array and being carried past
the array at a predetermined speed will observe
immediately following said predetermined time span the
said predetermined image as an apparently stationary image
occupying an area substantially larger than the area of
said array.
2. A system according to Claim 1, including sensing
means for monitoring the passage of a carrier carrying
said viewer past the array to trigger said controller into
action.
3. A system according to Claim 2, wherein said
sensing means comprises infrared sensing means arranged to
activate said controller upon the approach of said carrier
to the array and to deactivate the controller upon the
departure of said carrier away from said array.
4. A system according to Claim 3, wherein the
sensing means comprises a first infrared transmitter and
receiver pair located upstream of the array and a second
infrared and transmitter pair located downstream of the
array.
5. A system according to any one of claims 1 to 4
wherein the controller is arranged to cyclically repeat
the energisations specified by the predetermined program
at regular intervals.
6. A system according any one of claims 1 to 5, wherein
the array consists of light sources of different colours

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and wherein the predetermined program specifies different
durations of energisation of the different coloured light
sources.
7. A system according any one of claims 1 to 6, wherein
said controller is arranged to complete one cycle of the
predetermined program within a period of 0.015 seconds.
8. A system according to any preceding claim,
wherein the ratio of rows to columns in the array is 16:1
or greater.
9. A system according to Claim 1, wherein each
light source comprises a light emitting diode and the
controller includes a driver for driving each light
emitting diode, the driver being arranged to vary the
period for which its corresponding diode is energised in
accordance with the program stored in the memory.
10. An arrangement comprising a plurality of systems
each according to any one of claims 1 to 9 and a main computer
arranged to store a plurality of different programs each
representing a respective image, said main computer being
operable to replace the program stored in said memories
with a program stored in said main computer.
11. An arrangement according to Claim 10, wherein
said main computer is programmed to replace the program
stored in selected ones of the memories in accordance with
the time of day.
12. An arrangement according to Claim 10 or
Claim 12, wherein the computer is programmed to replace
the program stored in selected ones of the memories in
accordance with the location of their associated arrays.
13. A visual information display system comprising a
fibre optic array in which one end of a bundle of optical
fibres is arranged so that the ends of the individual
fibres at one end of the bundle form a vertically elongate
array of rows and columns and the ends of the individual
fibres at the opposite end of the bundle are connected to

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an electro-optical interface unit, and means for supplying
electrical signals to the interface unit to cause the
array to display a succession of images in sufficiently
quick succession that a viewer being carried horizontally
past the array perceives a single horizontally elongate
display consisting of said successive images located side
by side.
14. A display system according to Claim 13,
including a remote computer for generating data
representative of a desired display, a local data
interface for receiving the data, and a processor for
processing the received data and storing it in a memory,
the processor being arranged to control the interface unit
to respond to the data stored in the memory.
15. A display system according to Claim 13 or Claim
14, wherein the array is mounted on the wall of a train
tunnel and an on-board transmitter on a passing train
transmits the data from the computer to supply the
interface unit with said data.

Description

CA 02242807 1998-07-09
WO 97/25703 PCT/GB97/00096
VISUAL INFORMATION SYSTEMS
The present invention relates to visual
information systems.
Advertising is often presented in illuminated
form consisting of an array of fluorescent lights. Such
lights are usually switched on during the hours of
darkness. The array occupies the same area as the image
presented and consumes relatively large amounts of energy.
Such systems are relatively inflexible in as much as the
whole array needs to be rebuilt to display another image.
Other arrays of moving images are known in which
an array consisting of a plurality of rows and columns of
light sources are individually energisable to produce, for
example, a moving message. Such arrays have several times
more columns of light source than rows. Also, the size of
the array is the same size as the image and consequently
the wiring of individual light sources to the controlling
circuitry and the complexity of the control circuitry are
likely to be very costly.
It is an object of the invention to provide an
improved visual information system.
According to the present invention there is
provided a visual information system comprising an array
consisting of a plurality of individually and selectively
energisable light sources arranged in rows and columns, a
memory for storing a program representative of a
predetermined image, a controller actuatable to control
the selection and sequence of energisation of the light
sources within a predetermined time span in accordance
with the predetermined program stored on the memory so
that a viewer observing the array and being carried past
the array at a predetermined speed will observe
immediately following said predetermined time span the
said predetermined image as an apparently stationary image
occupying an area substantially larger than the area of

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said array.
According to the present invention there is
further provided a visual information display system
comprising a fibre optic array in which one end of a
bundle of optical fibres is arranged so that the ends of
the individual fibres at one end of the bundle form a
vertically elongate array of rows and columns and the ends
of the individual fibres at the opposite end of the bundle
are connected to an electro-optical interface unit, and
means for supplying electrical signals to the interface
unit to cause the array to display a succession of images
in sufficiently quick succession that a viewer being
carried past the array perceives a single horizontally
elongate display consisting of said successive images
located side by side.
Visual information system embodying the
invention will now be described, with reference to the
accompanying diagrammatic drawings, in which:
Figure 1 is a front elevation of the system;
Figure 2 is a black diagram of the system;
Figure 3 is a more detailed block diagram of the
system;
Figure 4 is a block diagram of another form of
system embodying the invention; and
Figure 5 is an end view of a train passing
through a tunnel and illustrating the positioning of the
system.
The visual information system to be described is
arranged to be located in tunnels through which public
3o transportation vehicles such as tube trains normally run.
The system consists of a series of light source arrays 2
arranged at spaced intervals along the track 4 on the side
wall of the tunnel, generally level with the windows of
the train so that the arrays can be viewed by the
passengers in the train. A sensor 6 located upstream of

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each array 2 is responsive to the approach of the train to
the array to actuate the array. Another sensor 8 located
downstream of each array is responsive to when the train
a has passed to deactivate the array 2. The sensors 6 and 8
may take the form of infrared transmitter and receiver
pairs.
Each array 2 consists of four columns and sixty
four rows of individually and selectively energisable
light sources for example light emitting diodes.
Selected light sources in the array are switched
ON and OFF by a controller 10 in accordance with a
predetermined program stored in a memory 12. The
controller is triggered by the sensor 6 and the program is
cyclically repeated until a signal is received from the
sensor 8.
The switching rate of the light sources and the
duration of their energisation is such that a passenger
sitting in the train and keeping his eyes directed at the
array will observe an image several times wider than the
width of the array.
The effect is achieved because with light
flashes of very short duration, the reaction of the human
eye to the flash persists long after the flash has
finished. Thus, where a series of very short flashes
occur over a short time span less than 0.015 seconds, all
the flashes appear to the eye to have occurred at the same
time and when the flashes are spaced from one another on
the retina because the viewer has moved relative to the
array, the eye perceives a composite light pattern which
will persist for a short while immediately following the
n
time span. It will thus be appreciated that a program can
be created and stored in the memory 12 which will produce
a.
almost any desired image for the observer. The image may
take the form of alpha numeric information or my take the
form of an advertising poster.

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The block diagram of the system is mare clearly
shown in Figure 3.
As can be seen, the array 2 consists of a series
of light emitting diodes 20. In this arrangement only
sixteen are shown, arranged in a single column. Each LED
has a power output of 32 mcd's and has a high switching
speed with a switching time faster than 10 nanoseconds.
The controller 10 includes a driver 22 which
acts to drive the LED's 20 through respective resistors
24. The driver 22 is controlled by a central processing
unit (CPU) 26 which derives its instructions from terminal
1 of the memory 12 via resistors R36 and R34 which feed
terminal 5 of the CPU. The memory 12 is in the form of an
erasable programmable read only memory (EPROM).
The CPU 26 is triggered into action by a signal
received on terminal 28 from the sensor 6.
The CPU cyclically repeats the program stored in
the EPROM 12 at a repetition rate in the range of from 10-
50 Hz but is preferably 15 Hz.
By updating the memory periodically the
passengers will be able to observe different images.
When a large plurality of arrays are provided
they can be divided into groups with the memory of the
system in each group being updatable simultaneously. A
central computer (not shown) is provided to store a
plurality of different programs. The central computer is
connected to each group to update the memory in each group
with a new program depending either upon the time of day
or the location of the group.
When a colour image is required, each light
source of the array can be replaced by a row consisting of
red, green and blue elements or a row consisting of red,
green, blue and white light elements. Each element is
selectively energisable. It will be appreciated that by
having the program determine, the period of energisation

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of each light source, the shade of colour in the final
image can be varied as required.
While the rows and columns in each memory can be
varied, it is preferable that the ratio of rows to columns
in the array is 16:1 or greater.
In the embodiment shown in Figure 4, the optical
array 20 consists of an array formed by the exposed ends
of a bundle 22 of optical fibres. The opposite ends of
the electro~-optical fibres of the bundle 22 are connected
'to an electro-optical interface unit 24. Data
representative of a desired image to be displayed is
transmitted from a central computer 32 by radio optical or
direct wire link to a data interface unit 30 which passes
the signals to a processor 28 which in turn causes the
signals to be stored in a storage unit 26. The processor
28 is responsive to a local trigger such as the sensors 6
and 8 described in connection with Figures 1 and 2 or a
remote trigger, to cause the electro~-optical interface to
read out the stored data from the memory 26 and to cause
the corresponding image to be progressively reproduced on
the display 20 in a manner such as that described in
conjunction with Figures 1 to 3.
The central computer 32 can be programmed to
send different displays to different groups of optical
arrays as required and alter the displays stored by the
memories 26 at different times of the day, week and/or
month.
In the embodiment show in Figure 5, a train 36
within a tunnel 34 carries an on-board transmitter 38
which is connected to an on-board or a remote central
computer 32. Data from the computer 32 is transmitted by
the transmitter 38 to a receiver 40 adjacent a display 20
mounted on the wall of the tunnel. The receiver is
connected to the data interface 30 (see Figure 4) of the
display from whereon the system operates in the same

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manner as described in connection with Figure 4.
The transmitter and receiver may be acoustic,
optical or radio. Also, the train may have an on-board
speed monitor and data representative of the speed of the
train transmitted to the processor 28 so that the
processor can modify the rate that the electro-optical
interface reads signals from the memory 26 in a manner to
synchronise the display with the speed of the train.
In a modification, instead of the interface 24
reading signals from the memory 26, the memory 26 can be
omitted and the signals read in real time from the
processor 28.

Representative Drawing