Method and apparatus for manufacturing an optical disc having a light-transmitting layer of a uniform thickness over the entire surface of a substrate is provided whereon a recording andor a reproducing of information signals is carried out by a light input through the light-transmitting layer. Through the design of external electrodes and a circuit control unit, the refraction index of the liquid crystal medium can be modulated by the external voltage so that the beam passing through the LCD produces diffraction. In the second pixel, a second transistor is coupled to a second storage capacitor via a second pixel electrode.