Tête de lecture optique

Optical pickup head

Optischer Wiedergabekopf

Abstract

An optical pickup head for operating on an information recording medium includes a light source for emitting a light beam. A transparent base plate has opposite surfaces formed with a semitransparent film and a hologram respectively. The semitransparent film is exposed to the light beam emitted from the light source, and reflects a portion of the light beam emitted from the light source. The portion of the light beam which is reflected by the semitransparent film forms a forward light beam. A condenser optical system serves to focus the forward light beam on the information recording medium. The forward light beam is reflected at the information recording medium, and forms a backward light beam. The backward light beam successively passes through the condenser optical system, the semitransparent film, and the transparent base plate, and then reaches the hologram. The hologram generates a backward +1-order diffraction light beam from the backward light beam. A plurality of photodetectors serve to receive the +1-order diffraction light beam and to convert the received +1-order diffraction light beam into corresponding electric signals respectively.

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Patent Citations (3)

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NO-Patent Citations (0)

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Cited By (7)

    Publication numberPublication dateAssigneeTitle
    CN-1049063-CFebruary 02, 2000松下电器产业株式会社Optical head device and optical information apparatus
    EP-0627733-A1December 07, 1994Matsushita Electric Industrial Co., Ltd.Optische Kopfvorrichtung und optisches Informationsgerät
    FR-2754096-A1April 03, 1998Daewoo Electronics Co LtdDispositif a capteur optique de type compact
    FR-2754097-A1April 03, 1998Daewoo Electronics Co LtdDispositif a capteur optique
    FR-2755282-A1April 30, 1998Daewoo Electronics Co LtdSysteme capteur optique de taille reduite
    US-5687153-ANovember 11, 1997Matsushita Electric Industrial Co, Ltd.Optical head device and optical information apparatus using a lithium niobate hologram with divisional areas to diffract light to corresponding photo detector areas
    US-5939710-AAugust 17, 1999Daewoo Electronics Co., Ltd.Optical pickup system incorporating therein a beam splitter having a phase layer