| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical disk exposure device capable of maintaining stable focus state even when the spatial intensity distribution of a laser beam varies depending on the time. <P>SOLUTION: By reading changes in beam shape, the position of a four-divided optical detector 113c is corrected according to the variation of the beam to thereby cancel the variation of the spatial intensity distribution in the light intensity of the beam entering into the four-divided optical detector 113c due to the variation of the beam shape. Thus, the variation of the focus state is prevented. <P>COPYRIGHT: (C)2013,JPO&INPIT |
