Traffic Light question.

[jayanth.devarayanadurga]

Why three lights are used in Traffic lights? R, Y, G are used when it can be replaced by RBG leds. So, only one light if enough. R and G are primary and Y can be obtained by turning on R and G simultaneously. Is it a better idea to replace 3 light Traffic system with one RGB (RYG) light system?

 

[keith1200rs]

Position is important. Anyone who is colour blind wouldn't be able to tell which light is on but they can by position. This is also true for guide dogs, I believe (although not when driving cars!).

Keith

 

[jayanth.devarayanadurga]

But that problem can be solved by using a single RGB matrix display which can display R, Y, G character on the display when that particular color is ON or it can also display S, R, P (Stop, Ready, Proceed) using R, Y, and G colors. Even the same display can display any pointers for straight, right, left etc...

 

[keith1200rs]

Letters aren't multilingual. Arrows don't necessarily help - I have seen arrows which are illuminated red which means "don't proceed".

Keith

 

[jayanth.devarayanadurga]

I think it will be helpful if a standard is made to display 3 symbols for S, R, P which can be used in any country. I think this will work finally. A palm symbol for Stop, an arrow for Proceed and some other symbol for Get ready. Atleast people all over the world can recognize symbols.

 

[hexreader]

I think it will be helpful if a standard is made to display 3 symbols for S, R, P which can be used in any country.

But why try to make the whole world adopt a new standard, when the existing standard has worked brilliantly throughout the world for a hundred years or more?

How many disasters will result from a change-over and how much money will it cost?

Seems like a total non-starter to me.

... and I agree with keith1200rs. Position is important, not just for the colour blind, but as a second cue to the fully-sighted.

"sorry officer, was that a palm? it looked like an arrow to me, with my tired eyes at that distance".

 

[ZASto]

There are many different languages across the world, there is no way to "enforce" a new "standard" for traffic lights. Colours are quite enough. As Keith pointed out, position is relevant (colour impaired, guide dogs ...). Even, in some countries traffic signs are not enough so they are backed up with text based addons - USA (how 'bout illiterates :smile