Patent FR2598521A1 successfully refreshed from Google Patents.
FR2598521A1
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Optical system for a photoelectromagnetic recording and reproduction device
Assignee: Pioneer Corp
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Filing: 1987-05-12
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Granted: —
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Expires: 2007-05-12
Abstract
Abstract The invention relates to a photoelectromagnetic reproduction device in which the reflected light signal coming from a photoelectromagnetic disc 24 is split by an astigmatic analyser 28. The analyser splits the light signal as a function of the linear polarisation, with the purpose of detecting the data signal, but furthermore introduces some astigmatism into one of the split beams in order to permit a focusing detection. … …
Inventors
- 👤 Yoshihiro Utsumi
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-09 06:53
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/1055; G11B11/10576; G02; G02B; G02B27/00; G02B27/10; G02B27/16; G11B11/10532
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References Cited (Backward Citations)
US4451863A
Cited
DE3429382A1
Cited
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