1. In a strict sense, the visible Spectrum nominally covering the WavelengthRange of 400 NM to 750
nm. 2. In the Laser and optical communications fields, the much broader portion of the electromagnetic
spectrum that can be handled by the basic optical techniques used for the visible spectrum extending
from the near-ultraviolet region of approximately 0.3 micrometers through the visible region and into
the mid-infrared region to 30 micrometers.