Light is an ultra-high frequency electromagnetic(EM) wave that travels at 2.998 ×10^8 m/s. Light amplitude is measured in foot-candles (fc) or lux (lx). The wavelength of visible light is from 4 × 10^−7 m to 7 × 10^−7 m. Longer wavelengths of electromagnetic(EM) waves are termed infrared, and