Photosensor

Abstract

Abstract PURPOSE:To increase optical response speed by forming an auxiliary electrode through an insulator layer at a position facing a beam incident clearance in an electrode while holding a photoconductive layer and applying bias voltage. CONSTITUTION:An auxiliary electrode 6 in Ni on a substrate 1 is coated with an SiO2 film, and a pair of electrodes 3, 4 are superposed through a photoconductive layer 2, and coated with a protective film 5. The auxiliary electrode 6 is W wide, and is formed where facing a clearance (a) between the electrodes 3, 4, and W<=a is formed. Voltage E applied to a photosensor and reversed polarity bias voltage Eg1>Eg2 are changed over alternately, and applied to the auxiliary electrode 6. Eg2 is applied on the reading of optical informations (beam projection to the photoconcuductive layer 2) and Eg1 on non-reading (no beam-projection). Accordingly, the photoconductive layer 2 is reverse-biassed sharply on non-reading, a rise time in the layer 2 is shortened largely, and the optical response speed of the layer 2 is increased substantially on the reading of intermittent optical informations.

Inventors

• 👤 Tsutomu Ishida
• 👤 力 石田

Bibliographic Details