Abstract: A convergence adjustment circuit and a projection type display apparatus provided with convergence adjustment circuit, including a fixed gain adjustment circuit which controls the waveform and level of an analog signal, wherein the analog signal is adjusted roughly in the fixed gain adjustment circuit and (the analog signal is adjusted) finely in the digital adjustment circuit thereby reducing the effect of the temperature characteristics and resolution the effect of the temperature characteristics and resolution and making it possible to carry out adjustment of convergence with high accuracy. A geomagnetism sensor circuit may also be provided for sensing changes in geomagnetism and outputting a signal for adjusting convergence to cancel out the effects of geomagnetism.

Abstract: A back-projection picture display apparatus which consists of a cabinet including a back-projection screen with a Fresnel lens plate, a video projector unit housed within the cabinet, and a remote control system including a remote controller for generating an infrared beam of a particular characteristic descriptive of a particular command with which the apparatus is operated and a command sensor operable in response to the infrared beam to operate the apparatus to accomplish a mode of operation assigned by such particular command. The command sensor is housed within the cabinet and arranged at a location where the infrared rays of light passing through the Fresnel lens plate are converged.