Amplifiers are used to amplify the energy output of photodetectors as well as convert their electrical signal for a number of illumination measurement or spectroscopy applications. Amplifiers are digital systems that amplify the low electrical current transmitted by photodetectors to easily detectable levels. Amplifiers also convert photodetectors’ electrical current into voltage so that their signal may be read by other digital devices. Amplifiers are indispensable for nearly any light measurement applications by greatly increasing the usability of a detector system.