Abstract: A cutting machine for cutting pits on a laser disc master comprising a disc signal source with a RAM and a series of shift registers; a machine unit having a servo-rotary shaft for mounting a master disc; a servo-horizontally moving shaft perpendicular to the rotary shaft; a deviation sensor mounted on the horizontally moving shaft perpendicular to the master disc; and a diamond cutting tool controlled by a signal-source-controlled piezoelectric driver. It also comprises a computer unit, which includes a disc signal control interface, and machine unit control interfaces. The rotation error of the machine unit can modulate the signal output speed of the signal source.