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Saab is the only car manufacturer that uses green illumination of the dashboard instrumentation. Is it true that green is easiest on the eyes?

On long drives, I certainly haven't noticed my eyes getting tired with green.
 

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The eye is more sensitive to green than any other color. What this translates to in terms of dash illumination, I don't know, but I prefer it to red. (Red has an advantage that it affects night vision less, but it is also hard to focus on.)

I must admit that at night the Saab's interior is a veritablle Christmas Tree of green lights.
 

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DrSandman said:
Saab is the only car manufacturer that uses green illumination of the dashboard instrumentation. Is it true that green is easiest on the eyes?
Saab isn't the only one to use green by any means. Many Japanese and other European manufacturers use green illumination.

Short wavelength colours, like blue, tend to be very tiring on the eyes in dark situations. Blue is very clear though. At the other end of the spectrum, red is much easier on the eye, but is harder to focus on.

Green is pretty much in the middle - not too tiring on the eyes whilst being easy to read. The instrumentation in the Saab also remains very legible even when the illumination is turned right down.

It also helps that you've only got one colour - unlike VW's with their garish red pointers on blue scales...
 

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DrSandman said:
Saab is the only car manufacturer that uses green illumination of the dashboard instrumentation. Is it true that green is easiest on the eyes?

On long drives, I certainly haven't noticed my eyes getting tired with green.
Thought the Doc might have the answers for us here...or are you something other than a physician?

Anyway, I heard several years ago when I had a Passat they used green for one year (97-98) then switched to blue that both of these colors are easiest on the eyes. Not sure if that's true or not.
It seems fighter jets and airplanes use green and blue as well.
 

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I can't comment on physiologically why, but I do like the green lighting. I do wish the dimmer would allow further dimming. In my other cars, the dimmer allows a continuous gradient to darkness. This would not be such a big deal if the nightpanel function dimmed everything but the spedo and the nightpanel button.
 

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I think this Wikipedia quote explains it best.




SAABRoma said:
In biological night vision, molecules of rhodopsin in the rods of the eye undergo a change in shape as light is absorbed by them. Rhodopsin is the chemical that allows night-vision, and is extremely sensitive to light. Exposed to white light, the pigment immediately bleaches, and it takes about 30 minutes to regenerate fully, but most of the adaptation occurs within the first five or ten minutes in the dark. Rhodopsin in the human rods is insensitive to the longer red wavelengths of light, so many people use red light to preserve night vision as it will not deplete the eye's rhodopsin stores in the rods and instead is viewed by the cones.

Some animals, such as cats, dogs, and deer have a structure called tapetum lucidum in the back of the eye that reflects light back towards the retina, increasing the amount of light it captures. In humans, only 10% of the light that enters the eye falls on photosensitive parts of the retina. An animal's ability to see in low light levels may be similar to what humans see when using first or perhaps second generation image intensifiers.
 

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Add to that the discussion on the linked page indicating "Rods" influence on night vision compared to "cones" influence on day vision. Further, "rods" are most suceptable to green light. So if I have interpreted this correctly, we can see green light better at night at dimmer settings than that of a different color.

http://micro.magnet.fsu.edu/optics/lightandcolor/vision.html

Rod cells are most sensitive to green wavelengths of light (about 550-555 nanometers), although they display a broad range of response throughout the visible spectrum. They are the most populous visual receptor cells in humans, each eye containing about 130 million rods. Extremely responsive, the light sensitivity of rod cells is about 1000 times that of cone cells. However, the images generated by rod stimulation alone are relatively unsharp and confined to shades of gray, similar to those found in a black and white soft-focus photographic image. Rod vision is commonly referred to as scotopic or twilight vision because in low light levels it enables individuals to distinguish shapes and the relative brightness of objects, but not their colors.
 

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DrSandman said:
Saab is the only car manufacturer that uses green illumination of the dashboard instrumentation. Is it true that green is easiest on the eyes?

I know for certain that green is easy on eyes and on the overall well being even on long exposure. One reason why industrial machinery is painted mostly in green. Has anyone noticed that?:eek:
 

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GWC said:
Add to that the discussion on the linked page indicating "Rods" influence on night vision compared to "cones" influence on day vision. Further, "rods" are most suceptable to green light. So if I have interpreted this correctly, we can see green light better at night at dimmer settings than that of a different color.

http://micro.magnet.fsu.edu/optics/lightandcolor/vision.html
That's correct. Rods are more suceptable to green light, so it will be easier to see a green image at night.

However, during night driving, it is not seeing the dash, which should concern you the most. What you should be more concerned about is a piece of a truck tire in the middle of the road, or some a**hole driving around without his lights on.

"Extremely responsive, the light sensitivity of rod cells is about 1000 times that of cone cells. .... Rod vision is commonly referred to as scotopic or twilight vision because in low light levels it enables individuals to distinguish shapes and the relative brightness of objects"

Consider this analogy. Imagine if someone was to sound a bullhorn next to your ear. You would hear a ringing for a few minutes, and wouldn't be able to hear if someone was whispering.

It the same sense, the rods would be stimulated by a green light, and your nightvision sensitivity would be dimished for several minutes.

Since red lights are less stimulating to the rods, they would not greatly effect your eyes' sensitivity. And would be the preferable color of the dash during night driving.
 

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DrSandman said:
Saab is the only car manufacturer that uses green illumination of the dashboard instrumentation. Is it true that green is easiest on the eyes?

On long drives, I certainly haven't noticed my eyes getting tired with green.
I love SAAB, but they are not the only ones with Green illumination. Ford has been using green for a few decades.
 

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Counterpoint

SAABRoma said:
Since red lights are less stimulating to the rods, they would not greatly effect your eyes' sensitivity. And would be the preferable color of the dash during night driving.
I think I can make a counter argument to that (just conjecture on my part though). I think most of the light hitting the eyes during night driving is reflected white light from the headlights. So I don't think red dash lights would preserve night vision at all. I would prefer a low level of green to make reading the dash easier (for me at least), and I don't think the miniscule amount of green light would affect night vision at all for eyes already awash with reflected white light.
 

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ive noticed that that green is much easier on the eyes also, on the same drive from tampa to boca raton at night in my saab seemed less stress full when inmy vw with the purple blueish and red lightting it tended to hurt my eyes more so i didnt really pay attention to my speed as much :eek: but in my saab its alot better, easier to read during long drives !
 

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Another point to make is that for a near object our eyes exert less focusing (or accommodative) effort to maintain a sharp image of a green object than a red.



Green light has a shorter wavelength than red, and travels through the eye at a different speed (just as white light through a prism splits up into it's component colours). Green light from a near object tends to fall nearer the retina than red so requires less muscular/accommodative effort to achieve sharp focus.
 

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I don't have any scientific info, but can say that red dash lights are irritating to my eyes. Red just doesn't seem as defined as green/white. Part of the problem is the contrast between red and other colors as opposed to greens contrast to others.

Heck if warning lights are red, your red line is red, and your dash is red, what do you have?
 

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i am trying to find an article that explains why green and blue colors are the best for this situation.....

the same article refers also to the phenomenon when we see some objects at very high distances and they seem to be more blue-ish or more green-ish.
for example the slopes of a mountain or the sea-sky line.

if i find it i ll edit my post:cool:
 

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Unless you're near-sighted...

Aero said:
Another point to make is that for a near object our eyes exert less focusing (or accommodative) effort to maintain a sharp image of a green object than a red.



Green light has a shorter wavelength than red, and travels through the eye at a different speed (just as white light through a prism splits up into it's component colours). Green light from a near object tends to fall nearer the retina than red so requires less muscular/accommodative effort to achieve sharp focus.
Unless, of course, you're near-sighted and aren't wearing corrective lenses, then the situation flip-flops and red is easier to focus.:)
 

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saabyurk said:
Unless, of course, you're near-sighted and aren't wearing corrective lenses, then the situation flip-flops and red is easier to focus.:)
But I always wear my glasses....
 

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saabyurk said:
Unless, of course, you're near-sighted and aren't wearing corrective lenses, then the situation flip-flops and red is easier to focus.:)
Instead of wearing glasses, I have a prescription windshield. One day I was driving and everything went fuzzy....the prescription ran out.
 

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saabyurk said:
I think I can make a counter argument to that (just conjecture on my part though). I think most of the light hitting the eyes during night driving is reflected white light from the headlights. So I don't think red dash lights would preserve night vision at all. I would prefer a low level of green to make reading the dash easier (for me at least), and I don't think the miniscule amount of green light would affect night vision at all for eyes already awash with reflected white light.
You've got a good point. Pass me the ketchup, I'd like some on my humble pie.
 
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