Method and apparatus for optical head and optical information reproducing
AssigneeHitachi, Ltd.
InventorsKouji Arikawa, Shigeru Nakamura, Kazuo Shigematsu
Life of this patent
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Abstract
An optical head for reproducing information contained on an optical information disk includes a plurality of light sources and a plurality of light receiving elements in correspondence with the plurality of laser light sources. There is constructed a constitution in which one laser light source in the plurality of laser light sources is constituted by an individual laser diode and which includes a laser module constituted by other laser light sources and the plurality of light receiving elements to thereby enable to realize the small size of the optical head.
Claims14
An optical head for focusing laser light on an optical information medium and receiving the reflected light from the optical information medium comprising:
- a first laser emitting component;
- and
- a second laser emitting component,
- the second laser emitting component including:
- a first light receiving element;
- a second light receiving element;
- and
- a third light receiving element,
- wherein the first laser emitting component is configured to selectively produce laser light of a first wavelength and a second wavelength and the second laser emitting component is configured to produce laser light only of a third wavelength,
- wherein the first light receiving element is arranged to receive reflected laser light of the first wavelength,
- wherein the second light receiving element is arranged to receive reflected laser light of the second wavelength,
- wherein the third light receiving element is arranged to receive reflected laser light of the third wavelength,
- wherein the first laser emitting component comprises only a first single laser chip and the second laser emitting component comprises only a second single laser chip, the first single laser chip operable to selectively produce laser light of the first wavelength and laser light of the second wavelength.
An optical head for directing laser light to an optical information medium and for receiving the reflected laser light from the optical information medium, comprising:
- a first laser component disposed on a first substrate for emitting a first beam of light;
- a second laser component disposed on a second substrate for emitting a second beam of light, the second laser component further having a plurality of receiving elements, the second substrate being separate from the first substrate;
- a beam splitter to guide the beams of light to the optical information medium;
- and
- a focus lens to focus the beams of light onto the optical information medium, thereby producing reflected light from the optical information medium,
- the beam splitter guiding the reflected light to the receiving elements of the second laser component,
- wherein one of the first and second laser components is configured to produce laser at only a single wavelength and the other of the first and second laser components is configured to selectively produce laser at a first wavelength and at a second wavelength.
An optical head for focusing laser light on an optical information medium and receiving the reflected light from the optical information medium comprising:
- a first laser emitting component;
- and
- a second laser emitting component, the second laser emitting component including:
- a first light receiving element;
- a second light receiving element;
- and
- a third light receiving element,
- wherein the second laser emitting component is separate from the first laser emitting component,
- wherein the second laser emitting component is configured to selectively produce laser light of the first and the second wavelength and the first laser emitting component is configured to produce laser light of the third wavelength, the first wavelength, the second wavelength, and the third wavelength being different from each other,
- wherein the first light receiving element is arranged to receive reflected laser light of the first wavelength,
- wherein the second light receiving element is arranged to receive reflected laser light of the second wavelength,
- wherein the third light receiving element is arranged to receive reflected laser light of the third wavelength.
Dependencies are inferred from the claim text.