pigmented colorants: dependence on media and time - Cornell ...

Figure 3.9: The physical amount of energy from a surface is dependent
of the emitted light source E and the reflectance R of the material.
Adapted from [Ber00].
Figure 3.9 illustrates the spectra of a reflected light stimulus–resulting from the
combination of an emitted light and a material’s reflectance.
Similarly, to quantify a material’s transmitted light energy over all wavelengths,
P =
λ E(λ)T (λ), where T (λ) is the transmitted light energy at each wavelength.
3.1.3 Human Visual System
In understanding the human visual system, many compare the human eye to a
traditional camera. Both are optical devices designed to record visual images onto
light-sensitive material (film, in the case of a camera; photoreceptors, in the case
of our eyes). Both have controls for adjusting the amount of light that enters
the device, whether they are mechanical or biological. However, eyes are much
more powerful than just recording static data to film. They continuously recode
information and transmit signals to the brain for interpretation and reaction.
When looking at another individual’s eyes, one only sees a small portion of
the outer surface (approximately one-sixth). The human eye is approximately 24
millimeters, or slightly smaller than a ping pong ball [SB02]. Most of the eye is
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