Answer
A photographic light meter is used to measure the intensity of incident light radiation. Each photon of incident light induces a valence-band-to-conduction band electron transition in which both electrons and holes are produced. The magnitude of the photo induced current resulting from these transitions is registered, which is proportional to the numbers of electrons and holes and thus, the number of incident photons, or, equivalently, the intensity of the incident light radiation.
Work Step by Step
A photographic light meter is used to measure the intensity of incident light radiation. Each photon of incident light induces a valence-band-to-conduction band electron transition in which both electrons and holes are produced. The magnitude of the photo induced current resulting from these transitions is registered, which is proportional to the numbers of electrons and holes and thus, the number of incident photons, or, equivalently, the intensity of the incident light radiation.
