Defect detection device

Details Defect detection device Defect detection device

2007-06-12

2007-06-12

Tran, Thang V. (Department: 2627)

Dynamic information storage or retrieval

Condition indicating, monitoring, or testing

Including radiation storage or retrieval

Reexamination Certificate

active

10899008

ABSTRACT:
The defect detection device includes: an amplification section for amplifying a reflection signal corresponding to the intensity of light reflected from an optical disc according to a control signal indicating recording or playback; an envelope detection section for outputting an envelope of the amplified signal; a first pulse generation section for outputting a pulse when the level of the control signal changes; an integration section for integrating the envelope; a differential signal generation section for receiving the envelope as a first input signal and the integrated results as a second input signal and outputting a differential signal corresponding to the difference between these signals; and a comparison section for comparing the differential signal with a predetermined value and outputting the results as a defect detection signal. The second input signal is changed so as to reduce the possibility that the defect detection signal may indicate the presence of a defect over the duration of the pulse.

REFERENCES:
patent: 4832487 (1989-05-01), Mikuriya et al.
patent: 5027339 (1991-06-01), Yoda et al.
patent: 5357497 (1994-10-01), Ogawa
patent: 5777967 (1998-07-01), Ishibashi et al.
patent: 6172953 (2001-01-01), Kamiyama
patent: 6236032 (2001-05-01), Kamiyama
patent: 6791916 (2004-09-01), Tateishi et al.
patent: 6891785 (2005-05-01), Yamamoto et al.
patent: 6914861 (2005-07-01), Chou et al.
patent: 2003/0128639 (2003-07-01), Kikuchi et al.
patent: 2003-196853 (2003-07-01), None

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