KR880011751A - Focus error detection device of magneto-optical head - Google Patents

Focus error detection device of magneto-optical head Download PDF

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Publication number
KR880011751A
KR880011751A KR1019880003469A KR880003469A KR880011751A KR 880011751 A KR880011751 A KR 880011751A KR 1019880003469 A KR1019880003469 A KR 1019880003469A KR 880003469 A KR880003469 A KR 880003469A KR 880011751 A KR880011751 A KR 880011751A
Authority
KR
South Korea
Prior art keywords
magneto
focus error
error detection
incident
optical head
Prior art date
Application number
KR1019880003469A
Other languages
Korean (ko)
Inventor
아쯔시 후꾸모또
기요시 오사또
미찌오 오까
Original Assignee
오오가 노리오
소니 가부시끼 가이샤
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 오오가 노리오, 소니 가부시끼 가이샤 filed Critical 오오가 노리오
Publication of KR880011751A publication Critical patent/KR880011751A/en

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following

Abstract

내용 없음No content

Description

광자기 헤드의 촛점 에러 검출 장치Focus error detection device of magneto-optical head

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음Since this is an open matter, no full text was included.

제1도는 본 발명의 실시예의 λ/2판의 한 예의 평면도.1 is a plan view of an example of a λ / 2 plate of an embodiment of the present invention.

제2도는 광검출기상의 빔 스풋의 광강도 분포를 도시하는 도면.2 shows light intensity distribution of beam output on a photodetector.

제3도는 λ/2판의 다른 예를 도시하는 평면도.3 is a plan view showing another example of the λ / 2 plate.

Claims (1)

투명기판상에 자성층이 형성된 광자기매체를 사용하며, 직선평광의 접속빔을 상기 광자기매체의 투명기판을 투과해서 자성층에 입사시키며, 그 출사빔을 접속시켜서 원통형을 투과해서 검광자에 입사시키며, 그 검광자로부터 얻어진 직선 편광빔을 광검출기에 입사시키며, 그 광검출기로부터 비점수차 방식의 촛점 에러 신호를 얻도록한 광자기헤드의 촛점 에러 검출장치에 있어서, 입사직선편광의 편광면에 대해, 각각 22.5°±90°×n, -22.5°±90°×n(단, n=0, 1, 2, 3…)의 방향으로 광학축을 가지며, 그 입사편광면과 평행 또는 수직인 방향에 따라서 분할된 쌍을 이루는 1/2파장판부로 되는 1/2파장판을 상기 원통형렌즈의 입사광로에 배치해서 이루어지는 광자기헤드의 촛점 에러 검출장치.A magneto-optical medium having a magnetic layer formed on a transparent substrate is used, and a connection beam of linear light is transmitted through the transparent substrate of the magneto-optical medium to enter the magnetic layer, and the exit beam is connected to pass through the cylinder to enter the analyzer. A focus error detection device of a magneto-optical head in which a linearly polarized beam obtained from the detector is incident on a photodetector, and a focus error signal of astigmatism type is obtained from the photodetector, with respect to a polarization plane of incident linearly polarized light. , With optical axes in the direction of 22.5 ° ± 90 ° × n, -22.5 ° ± 90 ° × n (where n = 0, 1, 2, 3…), and in a direction parallel or perpendicular to the incident polarization plane Therefore, a focus error detection apparatus for a magneto-optical head formed by arranging a half-wave plate, which is divided into a pair of half-wave plate portions, in the incident light path of the cylindrical lens. ※ 참고사항 : 최초출원 내용에 의하여 공개하는 것임.※ Note: The disclosure is based on the initial application.
KR1019880003469A 1987-03-31 1988-03-30 Focus error detection device of magneto-optical head KR880011751A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP1987049615U JPH075549Y2 (en) 1987-03-31 1987-03-31 Magneto-optical head focus error detector
JP49615 1987-03-31

Publications (1)

Publication Number Publication Date
KR880011751A true KR880011751A (en) 1988-10-31

Family

ID=30872231

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1019880003469A KR880011751A (en) 1987-03-31 1988-03-30 Focus error detection device of magneto-optical head

Country Status (2)

Country Link
JP (1) JPH075549Y2 (en)
KR (1) KR880011751A (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2643586B2 (en) * 1990-11-09 1997-08-20 日本電気株式会社 Optical information recording / reproducing device
JP2643595B2 (en) * 1990-11-29 1997-08-20 日本電気株式会社 Optical head device

Also Published As

Publication number Publication date
JPH075549Y2 (en) 1995-02-08
JPS63157818U (en) 1988-10-17

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E601 Decision to refuse application