PURPOSE:To expand remarkably a recording region of an optical disc by changing the ratio of an exposure intensity forming a guide groove of a write laser beam to an exposure intensity for forming a pit in response to the irradiated position of a write laser beam on an optical disc. CONSTITUTION:When the irradiated position of the write laser beam is moved in the direction of a center point of the optical disc 8, switches 173,... are closed in order and the irradiated position of the write laser beam reaches the vicinity of the inner boundary of the recording region of the optical disc 8, the a peripheral information signal fN is fed from an input terminal 14N, a switch 19N is closed, and when equation is established in the relation of R171...R17N, where R172-R17N are resistance values of resistors 172-17N in parallel with a resistor 16, the level of an information signal in a write signal a' is increased rapidly as the irradiated position of the write laser beam approaches the center point of the optical disc 8 and the exposure intensity of the write laser beam is changed by setting each ratio of the equation. Thus, the recording region of the optical disc is expanded.
展开▼
