Projection screen liquid crystal

Liquid crystal on which a write operation is performed by a laser beam. The laser beam generated by a laser source 1 is applied via an optical control unit such as mirrors 5X galvanometer 5Y on the liquid crystal 10. The intensity of the laser beam applied to the liquid crystal is controlled by a unit 2 for varying the intensity of the laser beam. A write control unit 7 controls the mechanical displacement caused by the optical axis control unit and the control unit for varying the intensity of the laser beam. The energy of the laser beam applied to the liquid crystal can be maintained constant, thereby allowing to obtain a constant width of the written line, even during acceleration and deceleration of the optical axis control unit. (CF DRAWING IN BOPI)