EP0452953A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical head
Assignee: Panasonic Holdings Corp
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Filing: 1991-04-19
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Granted: —
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Expires: 2011-04-19
Abstract
Abstract In an optical disc recording-reproducing apparatus using a standard optical disc enclosed in a cartridge (1), an optical plate (19) for correcting various aberrations generated by a focusing lens (18) is comprised therein in order to allow use of a double recording optical disc enclosed in a standard cartridge of the same size; the optical plate (19) is placed in front of the focusing lens (18) when the double recording optical disc is used, and is removed from the front of the focusing lens (18) when the standard optical disc is used. <IMAGE>
Inventors
- 👤 Isao Satoh
- 👤 Sadao Mizuno
- 👤 Noboru Itoh
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:01
CPC Classifications
G; G11; G11B; G11B7/00; G11B19/00; G11B19/02; G11B19/12; G11B7/004; G11B7/0045; G11B7/005; G11B7/12; G11B7/135; G11B7/1365; G11B7/1369; G11B7/1392; G11B7/13925; G11B7/24; G11B2007/0003; G11B2007/0006; G11B7/00454; G11B7/241; G11B7/242; G11B7/243
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
128 words
An optical head comprising: laser light emitting means (9) for emitting laser light, collimating means (10,15) for collimating said laser light emitted by said laser light emitting means (9), focusing means (18) for focusing said laser light collimated by said collimating means (10) on a recording area of an optical disc (2), a beam splitter (11) for separating laser light reflected from said recording area (8) of said optical disc (2), laser light sensing mean (14) for detecting laser light separated by said beam splitter (11), at least one optical plate (19) for correcting aberration of said focusing means (18), and actuator means (20) for positioning said optical plate (19) between said optical disc (2) and said focusing means (18) or for removing said optical plate (19) therefrom.
Claim 2
Dependent Claim
138 words
An optical disc recording-reproducing apparatus comprising: laser light emitting means (9) for emitting laser light, collimating means (10) for collimating said laser light emitted from said laser light emitting means (9), focusing means (18) for focusing said laser light collimated by said collimating means (10) on a recording area (8) of an optical disc (2) for recording information by means of said optical head. a beam splitter (11) for separating laser light reflected from said recording area of said optical disc (2), laser light sensing means (14) for detecting laser light separated by said beam splitter, at least one optical plate (19) for correcting aberration of said focusing means (18), and actuator means (20) for positioning said optical plate (19) perpendicular to the optical axes of said focusing means (18) or for removing said optical plate (19) therefrom.
Claim 3
Dependent Claim
66 words
An optical disc recording-reproducing apparatus in accordance with claim 2, wherein said optical disc (2) is enclosed in a cartridge (1) having at least one identification pit (23) for identifying said optical disc (2) enclosed in said cartridge (1), and said identifying pit (23) is detected by a sensing means (3), hence said actuator means (20) is controlled by the output of said sensing means (3).
Claim 4
Dependent Claim
84 words
An optical disc comprising: a first substrate (30) of at least 0.6 mm thick having a recording layer (33) on one side thereof, a second substrate (31) of at least 0.6 mm thick having a recording layer (33) on one side thereof, and adhered to said first substrate (30) with adhesive substance (37) of at most 0.2 mm thick in a manner that the recording layer (33) of said second substrate (31) is faced to the recording layer (33) of said first substrate (30).
References Cited (Backward Citations)
No citation records indexed.
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