| 摘要 |
PURPOSE:To shorten the time required for verifying operation of written information on an optical disk. CONSTITUTION:By transmitting a laser light for writing through a diffraction grating, a first order diffracted light is generated together with a zero order diffracted light and g spot L0 by the zero order diffracted light and a spot L1 by the first order diffracted light are formed on the land part D1 of an optical disk D. When writing is executed by the spot L0 of the zero order diffracted light, by receiving a reflected return light from the spot L1 of the first order diffracted light which scans an area already written, information just after writing is reproduced. Basing on the return light from the first order diffracted light, the written information is confirmed and the time required for verifying operation is shortened. |
