Two Rays of Light: What Color is Projected?

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When two rays of different colors, such as red and green, cross each other, the colors projected on the wall remain distinct as red and green. However, the human eye perceives the combination of these colors as yellow due to the way our color receptors (cones) are stimulated. This perception occurs because the eye cannot resolve the two colors when viewed from a distance, leading to a mixed signal interpreted by the brain. The phenomenon is further explained by the fact that yellow light stimulates both red and green receptors similarly, resulting in the same perception. Understanding this interaction highlights the biological basis of color vision and perception.
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When two rays of different colors of light cross each other what color is projected on the wall? Say for example, red light, and green light cross each other, what is the ultimate color projected on the wall? Why don't the colors get mixed up?
 
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why does this happen?
 
lordy12 said:
why does this happen?
It's a matter of the biology of color vision and how our three color receptors (cones) are stimulated. (If you're mainly interested in the biological aspects, I can move this thread to that forum.) There's a bit here: http://en.wikipedia.org/wiki/Color_vision"
 
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lordy12 said:
When two rays of different colors of light cross each other what color is projected on the wall? Say for example, red light, and green light cross each other, what is the ultimate color projected on the wall? Why don't the colors get mixed up?

The colour(s) projected on the wall are (1) red and (2) green. Period.

The human eye is sensitive to both read and green, but our brains interpret the combination of the two as yellow.
 
lordy12 said:
When two rays of different colors of light cross each other what color is projected on the wall? Say for example, red light, and green light cross each other, what is the ultimate color projected on the wall? Why don't the colors get mixed up?
Try this experiment: draw thin red lines alternated with thin green lines with bright colours on a bright white paper, then look at this drawing from some metres apart. You can do the same on computer monitor with a drawing application. The human eye cannot resolve the two different colours more than a certain limit, so the two colours signals will be mixed in your phisiological apparatus. This mixed signal is perceived as "yellow". The fact that a (really) yellow light is perceived in the same way, is due to the fact that yellow light has an average wavelenght between that of red and that of green light, so it will stimulate red receptors and green receptors in our eye in the same way.
 
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