AU2011205199B2 - Symbol based traffic light system - Google Patents

Abstract

- 12 A set of traffic lights (10) for vehicle traffic is provided, comprising illuminated symbols representing and 5 distinguishing at least STOP (11) and GO (13) signals, wherein the symbol representing GO (13) is a tick. Figure 1

Description

Title Symbol Based Traffic Light System 5 Field This invention relates to traffic lights, and in particular to a new system to make traffic lights readily recognisable by colour blind people. 10 Background to the Invention In Australia, about 4 - 8 % of men and 0.5% of women are colour-blind. 15 Studies have shown that colour-blind people take longer to recognize signal colours than persons with normal vision and make twice as many errors in doing so. The available stopping distance for red-blind drivers facing a red light 20 may be dangerously reduced by as much as 39% to 100%. Below are some of the responses of participants of a test conducted by Morley G. Whillans, MD. [Can. Med. Assoc. J Vol 228, May 25, 1983 p1188]: 25 "I am confused by single blinking amber or red lights. I was told by the examiner that I would lose my licence if I had an accident connected to traffic lights and was at fault." 30 "I drive on the assumption that when I don't see the green (which to me looks white) it must be red, which I cannot see. On the other hand, leaving amber (which I see quite well) along with the green would be confusing to me, as I would not know ant warning." 35 "I cannot distinguish traffic signals at night on a street with many neon lights until I am close. I have had one accident attributable to colour blindness." - 2 Considering the high population of colour blind and the 5 possible dangers of their driving on the road, an effective traffic light system, which can be easily recognised by colour blind people, is very important. 10 Summary of the Invention The inventor has recognised that a key to providing an 15 improved traffic lights is not just to provide symbols that are distinguishable by non-colour features, but to provide symbols which are intuitively understandable by anyone. 20 In accordance with a first broad aspect of the invention there is provided a set of traffic lights for vehicle traffic, comprising illuminated symbols representing and distinguishing a plurality of signals including at least STOP and GO signals, wherein the symbol representing GO is 25 a tick. The traffic lights may be adapted for use at an intersection. In one embodiment, the symbol representing STOP is a cross. 30 35 In one embodiment, the one of the symbols represents CAUTION and is a crossed tick.

- 3 In one embodiment, the symbol representing CAUTION is a crossed forwards arrow. In one embodiment, the traffic lights include turn signals 5 and the symbol representing STOP is an arrow with an arrow head pointing in the direction of turning and with a vertical bar adjacent the arrow head. In one embodiment, the traffic lights include turn signals 10 and the symbol representing CAUTION is an arrow with an arrow head pointing in the direction of turning and with a dotted vertical bar adjacent the arrow head. In one embodiment, the symbols are formed by a cover with 15 a symbol-shaped aperture installed over or in each light. In one embodiment, the symbols are formed by disconnecting or removing selected LEDs in a bank of LEDs of a circular traffic light so as to illuminate the shape of the symbol. 20 In one embodiment, the symbols for each light are formed by selectively illuminating LEDs in a single bank of multicoloured LEDs. 25 The symbol based traffic lights of the invention will enable colour blind people to easily distinguish the signals, which will reduce the judgement errors of colour blind people dramatically. As in one embodiment the design can be made as a lens cover and would take less than an 30 hour to install. The cost is not high and the benefits in reduced accidents will be very considerable. Brief description of the Drawings 35 Figure 1 is a set of traffic signals in accordance with an embodiment of the invention, as replacements for standard round red, amber and green lights, typically controlling straightforward passage through an intersection.

- 4 Figure 2 is a set of traffic signals in accordance with an embodiment of the invention, as replacements for standard right-arrow red, amber and green lights, typically 5 controlling right turns through an intersection. Figure 3 is a set of traffic signals in accordance with an embodiment of the invention, as replacements for standard left-arrow red, amber and green lights, typically 10 controlling left turns through an intersection. Figure 4 shows a lens cover for one embodiment of the invention. 15 Detailed Description of embodiments Symbol Based Traffic Light System 20 Referring first to Figure 1, a set of symbols to replace red, amber and green typically used to control straightforward passage through an intersection is shown. Traffic signal set 10 comprises STOP signal 11 in the 25 shape of a cross that glows red when lit, replacing the usual circular red signal; CAUTION signal 12 in the shape of a crossed tick that glows amber when lit, replacing the usual circular amber signal; and GO signal 13 in the shape of a tick that glows green when lit, replacing the usual 30 circular green signal. In an alternative embodiment of straight forwards signals, the crossed tick and ticks of the embodiment shown in Figure 1 may be replaced by a crossed or blocked forwards 35 pointing arrow for CAUTION and a forwards pointing arrow (i.e. pointing vertically up in the third dimension) for GO respectively.

- 5 Referring now to Figure 2, a set of symbols to replace red, amber and green right arrows typically used to control right turn at an intersection is shown. Traffic 5 signal set 20 comprises STOP signal 21 in the shape of a blocked right arrow that glows red when lit, replacing the usual red arrow signal; CAUTION signal 22 in the shape of a partially blocked right arrow that glows amber when lit, replacing the usual amber arrow signal; and GO signal 23 10 in the shape of a right arrow that glows green when lit, replacing the usual green arrow signal. Referring now to Figure 3, a set of symbols to replace red, amber and green right arrows typically used to 15 control left turn at an intersection is shown. Traffic signal set 30 comprises STOP signal 31 in the shape of a blocked left arrow that glows red when lit, replacing the usual red arrow signal; CAUTION signal 32 in the shape of a partially blocked left arrow that glows amber when lit, 20 replacing the usual amber arrow signal; and GO signal 33 in the shape of a left arrow that glows green when lit, replacing the usual green arrow signal. The invention thus provides symbols that are readable and 25 understandable by all road users, irrespective of native language, and that are easy to read at distance without reference to the colour, by maximising lit area as much as possible without sacrificing readability. 30 Lens Cover and Installation Procedure To convert a conventional traffic light set into the Symbol Based Traffic Light System of the current invention, the procedure below may be followed: 35 First, the symbol templates shown in Figs 1, 2 and 3, are enlarged to the same size as an existing traffic lens and a lens cover is made using a thin sheet made of aluminium - 6 alloy, plastic or other durable material. For a lens with non-flat surface (for example, convex or concave) facing the lamp, the lens cover should be shaped to match it. Next, the glowing part of the symbol is cut out of the 5 sheet. Then, the traffic light housing is opened, a lens disassembled from its frame, and the new lens cover is placed onto the surface of the lens facing the lamp. 10 Finally, the lens and the lens cover are placed together back into the lens frame and the traffic light house is closed and locked. 15 When an existing lens is fixed to a traffic light housing without a frame around it, a lens cover 40 with fixing tabs 41, 43, 43 and 44 may be prepared as shown in Figure 4 and bolted into place. Preferably, the diameter of the lens cover is 1-2 mm more than the diameter of the lens, 20 to allow for position adjustment during installation. Tabs 41-44 are shaped and positioned so as to allow fixing of the lens cover 40 to the internal surface of the lens using the existing lens fixing bolts, and have a bolt receiving aperture about 2 mm wider than the diameter of 25 the bolt, to allow for adjustment. The number, shape and size of tabs and the size will vary according the individual design of the traffic light housing. 30 Procedure to Convert LED Traffic Lights To convert LED traffic lights into the symbol based the 35 traffic light system according to the invention, for example to convert the usual circular Green/Amber/Red lamp into a tick/crossed tick/cross lamp respectively, it may be possible to simply disconnect or remove the LEDs corresponding to the black area of the symbol. Alternatively, the symbol templates shown in Figure 1 may be enlarged to the same size as an existing traffic lens 5 and a lens cover made using thin sheet made of aluminium alloy, plastic or other durable material with one side having adhesive material (basically, this makes a sticker). For a lens with a non-flat surface (for example, convex or concave) facing the lamp, the lens cover should 10 be shaped to match it. The area corresponding to the glowing part of the symbol is then cut out and then the lens cover is then stuck to the lens. A further alternative is to take the symbol templates 15 shown in Figure 1, enlarge them to the same size as an existing traffic lens and make a lens cover using thin sheet made of aluminium alloy, plastic or other durable material. For lens with non-flat surface facing the lamp (for example, convex or concave), the lens cover is shaped 20 to match it. The glowing part is then cut out of the sheet and then assembled to one surface of the lens. For further details refer to the above section "Lens Cover and Installation Procedure". 25 - 8 3 in 1 Single Traffic Lamp for multicolor LED Symbol Based Traffic System 5 With multi colour LEDs (a LED with capacity to display Green, Amber, and Red), together with invented symbols in Table 2, a 3 in 1 Single Traffic Lamp may be provided as follows, for the example of straight forwards signals: 10 1. Overlay 3 Symbol templates shown in Figure 1 on one round circuit board, and assemble LEDs in a matrix in the lit area. 15 2. Connect all green pins in Green Tick area to a Green Wire; Connect all amber pins in Amber Crossed Tick area to a Amber Wire; Connect all red pins in Red Cross area to a Red Wire; Connect all ground pins to a Black Wire. 20 3. Connect above Green Wire, Amber Wire, Red Wire and Black Wire to the corresponding outlet of the Traffic Light Controller. 25 The above steps 1-3 makes one 3 in 1 Single Traffic Lamp, which can displays Green Tick, Amber Crossed Tick and Red Cross. To make the corresponding left or right turn 3 in 1 Single traffic lamp, the symbols in Figures 2 and 3 are substituted. 30 Persons skilled in the art will also appreciate that many variations may be made to the invention without departing from the scope of the invention. 35 In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as - 9 "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. 5 It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any 10 other country.

Claims (9)

1. A set of traffic lights for vehicle traffic, comprising illuminated symbols representing and distinguishing a 5 plurality of signals including at least STOP and GO signals, wherein the symbol representing GO is a tick.

2. A set of traffic lights as claimed in claim 1, wherein the symbol representing STOP is a cross. 10

3. A set of traffic lights as claimed in any one of claims 1 or 2, wherein one of the signals represents CAUTION and is a crossed tick or crossed forwards arrow. 15

4. A set of traffic lights as claimed in claim 1, wherein the traffic lights include turn signals and the symbol representing STOP is an arrow with an arrow head pointing in the direction of turning and with a vertical bar 20 adjacent the arrow head.

5. A set of traffic lights as claimed in claim 1, wherein the traffic lights include turn signals and one of the symbols represents CAUTION and is an arrow with an arrow 25 head pointing in the direction of turning and with a dotted vertical bar adjacent the arrow head.

6. A set of traffic lights as claimed in claim 1, adapted for an intersection. 30

7. A set of traffic lights as claimed in any one of claims 1 to 6, wherein the symbols are formed by a cover with a symbol-shaped aperture installed over or in each light. 35

8. A set of traffic lights as claimed in any one of claims 1 to 6, wherein the symbols are formed by disconnecting or removing selected LEDs in a bank of LEDs of a circular traffic light so as to illuminate the shape of the symbol. - 11

9. A set of traffic lights as claimed in any one of claims 1 to 6, wherein the symbols for each light are formed by selectively illuminating LEDs in a single bank of 5 multicoloured LEDs.