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Thread: How do we see light and colors?

  1. #1 How do we see light and colors? 
    Forum Freshman
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    Alright, so if light/radiation spreads and goes out in every direction, how can see consist shapes, and colors? For example:



    I know that we can see different colors because of differences in the wavelenght and frequency of each photon. However, what keeps me seeing red and orange instead of a mixture of the colors since the photons would be going in all sorts of directions and cause interference, making it a mixture of the colors. Does have to do with the angle that the photon hits the lens? The way my physics teacher gave me notes, it almost looks like the eye can only focus on parrell lines, which made sense at first. However, that would be absurb, or else we could never change our field of vision by moving towards or away from an object. The light photons would always be the same

    My second question is about light from lasers and flashlights. One does not have to look at the source of emission (the actual laser or the actual light) to see it. However, if you just looked at a simple object, that would not be the case. Does this have something to do with the magnitude of the light? Does it make a difference if an object absorbs or reflects light from another source or from its own source whether nuclear, chemical, eletrical, etc.


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  3. #2  
    Time Lord
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    Imagine a sprinkler, one of those circular ones that spin around and around throwing out a stream of water. If you're standing near the sprinkler, and you get hit by the water, you know what direction it came from to hit you.

    That's what they mean by light going out in all directions. However it doesn't arrive at you from all directions. It only ever arrives from the direction it was emitted.

    As for seeing color, different wavelengths do different things when they hit the little recepticles in the back of the eye a, and your body is skilled at distinguishing what each thing means. A subconscious part of your brain pre-assembles/processes the information into a picture before it actually reaches your conscious mind.

    As for focusing: there's a lens in your eye, exactly like the lens in a telescope, and the lens is actually physically brought into focus in a similar way by muscles inside the eye. (Similar, but not identical. The way the eye adjusts it has to do with quishing it to change the lenses shape.)
    [/b]


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  4. #3  
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    It's depend on the speed of things. You see, If we have the circle like this one :

    The range of the waves are different, so the color we received is different. When we look at a color, its photons will impact our eyes and the eyes will send signals to the brain, so we realize different colors
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  5. #4  
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    It also has to do with the magnitude of the light source. If it is high enough, the colors emitted, say form the LCD I'm using right now, will form an aural area around them, as if they were flashlights. This would cause some color mixing, but as explained our minds are very good at properly observing the visible spectrum. Our minds fall short in things like observing say, a fish in the water, where the refraction of the water causes a bend that our minds cannot compensate for, causing the object to appear closer.
    Of all the wonders in the universe, none is likely more fascinating and complicated than human nature.

    "Two things are infinite: the universe and human stupidity; and I'm not sure about the universe."

    "Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence"

    -Einstein

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