Optical sensor having current amplifier including at least one thin-film transistor, and display apparatus provided with the optical sensor

摘要

An optical sensor includes a photoelectric converter to receive external light and to output a photocurrent signal according to the illuminance of the external light. A current-to-voltage converter converts the photocurrent signal output from the photoelectric converter to a voltage signal. A voltage amplifier amplifies the voltage signal. A current amplifier outputs a current signal corresponding to the voltage signal amplified by the voltage amplifier. Each of the photoelectric converter, current-to-voltage converter, voltage amplifier and current amplifier includes at least one thin-film transistor.