@B_and_D_T That’s the wrong end of the spectrum. The glowforge operates in the Infrared portion of the spectrum. If it helps the spectrum goes from xrays at really short wave lengths, through ultra violet to the visible colors of the rainbow violet,indigo, blue, green, yellow, orange, and red then to Infra red at longer wavelengths.
decreasing wavelength would reverse that order and for the visible spectrum probably be the order most of us memorized.