7700 angstrom units propagated at a speed of about 186,300 miles per second, and including a similar form of radiant energy that does not affect the retina, as ultraviolet or infrared rays, a gleam or sparkle, as in the eyes...

Electromagnetic radiation with wavelengths capable of causing the sensation of vision, ranging approximately from 4000 (extreme violet) to (extreme red), 7700 angstroms...

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