发明名称 |
Lens position control method, lens position control apparatus, cutting method, and cutting apparatus |
摘要 |
A lens position control method is disclosed. Either an objective lens or a master disc having a resist material film on its substrate is moved, thereby changing a distance between the objective lens and the master disc surface. A return laser beam transmitted through the objective lens and reflected by the master disc surface is detected by a photodetector. The movement of either of them is stopped when the master disc is located near a focal point of the objective lens and the return laser beam is detected. Limit data is rewritten to data corresponding to a position obtained by adding a movement permission amount smaller than a working distance of the objective lens to the stop position. When the return laser beam is not detected, the movement which changes the distance between them is stopped at a position corresponding to the limit data. |
申请公布号 |
US8085627(B2) |
申请公布日期 |
2011.12.27 |
申请号 |
US20060458172 |
申请日期 |
2006.07.18 |
申请人 |
HASHIMOTO GAKUJI;SONY CORPORATION |
发明人 |
HASHIMOTO GAKUJI |
分类号 |
G11B7/00 |
主分类号 |
G11B7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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