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It is said that human eye can see light with wavelength approximately between 400nm and 700nm.

Are these upper and lower bounds same for every human? If not, what are the means and standard deviations of these upper and lower wavelength values for human eyes?

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    $\begingroup$ just the fact that people can be color blind should answer that for you. I think this question is more appropriate to a biology site, because color percetion depends on the biological receptors of the eye not in one to one correspondence with wavelength. $\endgroup$
    – anna v
    Feb 19, 2013 at 8:17

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Human eyes all use the same optical pigment photopsin, so they all have the same basic frequency response.

There are differences. For example cataracts will change the sensitivity of the eye to colour, and people with colour blindness have various defect to cone cells that affect colour response. However these are secondary effects.

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Basically every human sees the same spectrum as we all have the same four types of photoreceptors: rods and a cone for green, red, and one for blue light.

In very rare cases there are women who have a duplication of one of their cone genes (usually the red one). If one of those duplicates mutates slightly, this results in a kind of fourth type of cone (see it mentioned here at Wikipedia), so they see a different spectrum.

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    $\begingroup$ This is not entirely correct, there are multiple variants of each of the three colour photoreceptors that have slightly different response curves. I do not know whether these variants result in different minimum and maximum sensitivities. $\endgroup$
    – Jack Aidley
    Feb 19, 2013 at 11:45
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    $\begingroup$ Also, you've somewhat confused the women having a fourth type of cone too. What happens in some women is that they have two variants of the same colour photoreceptor (red, almost aways). $\endgroup$
    – Jack Aidley
    Feb 19, 2013 at 11:47
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    $\begingroup$ I've also read studies on intraocular lenses that suggested that the humans eye sensitivity to light changes with age. $\endgroup$
    – Alex Stone
    Feb 20, 2013 at 3:51
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    $\begingroup$ The variants would produce different maximum and minimum sensitivities. The bounds aren't sharp, they are soft. As light moves out of the visible spectrum the response gets weaker and weaker, but it's not just a sharp drop. So different variants of photoopsins would change those "boundaries". $\endgroup$
    – Resonating
    Aug 16, 2013 at 16:27

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