Patent EP0074796A2 successfully refreshed from Google Patents.
EP0074796A2
Expired / Lapsed
EP
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Video tape recorders
Assignee: Sony Corp
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Filing: 1982-09-08
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Granted: —
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Expires: 2002-09-08
Abstract
Abstract A video tape recorder includes a rotary magnetic head drum having a rotating member and a magnetic head (9) mounted on the rotating member, a laser element (LD) mounted on the rotating member, a current source (10) for supplying a constant current to the laser element (LD), a circuit for electrically connecting a coil (8) of the magnetic head (9) in parallel with the laser element (LD), a photoelectric conversion member (PD) fixed in the video tape recorder, and members (12, 15) for optically coupling the laser element (LD) with the photoelectric conversion member (PD).
Inventors
- 👤 Takao Ohira
- 👤 Makoto Niiro
- 👤 Daijiro Okihara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 17:32
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02; G11B15/12; G11B15/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
90 words
A video tape recorder comprising: a rotary magnetic head drum including rotating means and a magnetic head (9) mounted on said rotating means; a laser element (LD) mounted on said rotating means; means (10) for supplying a constant current to said laser element (LD); means for electrically connecting a coil (8) of said magnetic head (9) in parallel with said laser element (LD); photoelectric conversion means (PD) fixed in said video tape recorder; and means (12, 15) for optically coupling said laser element (LD) with said photoelectric conversion means (PD).
Claim 2
Dependent Claim
90 words
A video tape recorder comprising: a rotary magnetic head drum including rotating means and a magnetic head (9) mounted on said rotating means; a laser element (LD) mounted on said rotating means; means (10) for supplying a constant current to said laser element (LD); means for electrically connecting a coil (8) of said magnetic head (9) in parallel with said laser element (LD); photoelectric conversion means (PD) fixed in said video tape recorder; and means (12, 15) for optically coupling said laser element (LD) with said photoelectric conversion means (PD).
Claim 3
Dependent Claim
20 words
A video tape recording according to claim 1 wherein a capacitor (C) is connected in series with said coil (8).
Claim 4
Dependent Claim
21 words
A video tape recorder according to claim 1 wherein said coupling means comprises a lens (12, 15) and a mirror (17).
Claim 5
Dependent Claim
16 words
A video tape recorder according to claim 1 wherein said coupling means comprises an optical fibre.
Claim 6
Dependent Claim
61 words
A video tape recorder according to claim 1 further comprising a recording amplifier (20) for supplying a recording signal to said magnetic head (9), light emitting means (LD2) fixed in said video tape recorder for emitting a light corresponding to a recording signal, and means (22, 23, 12) for optically coupling said light emitting means (LD2) with said laser element (LD1).
References Cited (Backward Citations)
No citation records indexed.
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