responsitivity
Spectral photosensitivity is a characteristic value of photodiodes, phototransistors and image sensors. The photosensitivity is given as the ratio of the generated photocurrent to the incident light. It is expressed in amperes (A) or milliamps (mA) to watts (W). The spectral photosensitivity depends on the wavelength and can also be specified in the dimensionless ratio of absorbed photons to emitted electrons.