Cutting apparatus for an optical disc.

摘要

A cutting apparatus is provided, in which a recording laser beam from a laser light source (1) is ON/OFF-modulated by an optical modulating device (8) on the basis of a square output signal in which a video FM wave signal is pulse width modulated by an audio FM wave signal thereby to form exposure pits on a master disc (15,16). This cutting apparatus includes a photodetector (38) for receiving one portion of the recording laser beam irradiated on the master disc (15,16) from the laser light source (1) or a photodetector (38a) for receiving a reflected light of the recording laser beam irradiated on the master disc from the laser light source (1) and which is reflected on the master disc (15,16). A detected output signal from the photodetector (38,38a) is supplied through a low-pass filter (39,39a) to a control circuit which controls an intensity of an output laser beam from the laser light source (1) <IMAGE>