Method for testing axial rotation defect of optical head moment apparatus |
Title： |
| Method for testing axial rotation defect of optical head moment apparatus |
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Application Number： |
200510066030 |
Application Date： |
2005/04/22 |
Announcement Date： |
2005/10/26 |
Pub. Date： |
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Publication Number： |
1687990 |
Announcement Number： |
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Grant Date： |
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Granted Pub. Date： |
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ApplicationType： |
Invention |
State/Country： |
11[China|beijing] |
IPC： |
G11B 20/00, G11B 21/02, G01D 21/00 |
Applicant(s)： |
Tsinghua Univ. |
Inventor(s)： |
Ji Jiandong, Ma Jianshe, Pan Longfa, Qin Liqin, Ru Jigang, Shi Hongwei, Wu Jianming, Xu Duanyi, Zhang Jianyong, Zhu Jianbiao |
Key Words： |
optical head, moment apparatus, axial rotation defect, testing method |
Abstract： |
The invention relates to a method for detecting axial rotating defect of moment instrument of an optical head, firstly outputting sine signals at different frequencies; driving the moment instrument to dither in the focusing or tracking direction; casting a laser beam upon a reflecting point of an objective of the moment instrument to measure the dithering speed at the reflecting point; integrating the speed signal to obtain displacement response signals of the reflecting point by the excitation of the sine signals, drawing amplitude-frequency characteristic curves for focusing and tracking coils of the moment instrument and obtaining first order resonance frequencies of the focusing and tracking coils; according to the amplitude-frequency characteristic curves, judging the axial rotating defect of the moment instrument. The method is used to improve production technology and ensure the quality of product. |
Claim： |
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Priority： |
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PCT： |
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LegalStatus： |
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