not a teacher
The physical structure of the human eye enables it to sense light of wavelengths up to 0.0005 millimeters.
This is the preposition "of" used to indicate the material or substance of which something is made, what constitutes it.
A house of stone. The dress of fine silk. Light of a certain wavelength.
Think of it as, "Light (made up) of wavelengths up to 0.0005 millimeters".
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