EP0487816A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Tracking error detecting system for an optical disk player
Assignee: Pioneer Corp
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Filing: 1991-04-30
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Granted: —
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Expires: 2011-04-30
Abstract
Abstract A photodetector (e.g. 5) is divided into a pair of first segments and a pair of second segments by a common line (7). A total area of the first segments is larger than an area of a spot (6) reflected from an optical disk onto the first segments. The second segments are provided within the first segments. A total area of the second segments is smaller than the spot. A detecting circuit (e.g. 10, 11, 12) is provided for producing a tracking error signal (TE) by removing a difference between outputs of the first segments and a difference between outputs of the second segments.
Inventors
- 👤 Naoharu c/o Tokorozawa Koujou Yanagawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 22:38
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/094
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
A tracking error detecting system for an optical disk player comprising: a photodetector (e.g. 5) comprising a pair of first segments a total area of which is larger than an area of a spot (6) reflected from the optical disk onto the first segments, a pair of second segments provided within the first segments and a total area of the second segments being smaller than said spot (6); and a detecting circuit (e.g. 10, 11, 12) for producing a tracking error signal (TE) by removing a difference between outputs of the first segments and a difference between outputs of the second segments.
Claim 2
Dependent Claim
102 words
A tracking error detecting system for an optical disk player comprising: a photodetector (e.g. 5) comprising a pair of first segments a total area of which is larger than an area of a spot (6) reflected from the optical disk onto the first segments, a pair of second segments provided within the first segments and a total area of the second segments being smaller than said spot (6); and a detecting circuit (e.g. 10, 11, 12) for producing a tracking error signal (TE) by removing a difference between outputs of the first segments and a difference between outputs of the second segments.
Claim 3
Dependent Claim
19 words
The system according to claim 1 wherein the first and second segments are divided by a common line (7).
Claim 4
Dependent Claim
40 words
The system according to claim 2 wherein the detecting circuit includes circuit means for removing a difference between a difference based on all outputs of the first and second segments and a difference based on outputs of the second segments.
References Cited (Backward Citations)
No citation records indexed.
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