Optical head apparatus
First Claim
1. An optical head apparatus comprising:
- a light source;
a lens holder for retaining objective lens that converges emitted light emitted from said light source on optical recording medium;
a lens drive apparatus for driving said lens holder in the tracking direction at the least; and
a photo detector for receiving reflected light from said optical recording medium;
wherein said objective lens or said lens holder includes a light-blocking section that has spread out on both sides of the tracking direction and that is capable of blocking nonessential light from the said light source proceeding toward said optical recording medium by passing outside the effective diameter of said objective lens.
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Accused Products
Abstract
The present invention proposes an optical head apparatus provided with light-blocking structure that can reliably prevent nonessential light from reaching the photo detector, without being an impediment to miniaturization and flattening, moreover, without increasing manufacturing cost. In an optical head apparatus, and in a lens holder, light-blocking section is provided that blocks nonessential light from passing outside the effective diameter of objective lens. This light-blocking section is constructed so that it extends only in tracking direction T of objective lens 5. Further, light-blocking face of light-blocking section slants at an angle of 1° or more toward the face orthogonal to the optical axis, consequently, nonessential light is reflected in a direction other than the direction of photo detector.
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Citations
7 Claims
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1. An optical head apparatus comprising:
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a light source;
a lens holder for retaining objective lens that converges emitted light emitted from said light source on optical recording medium;
a lens drive apparatus for driving said lens holder in the tracking direction at the least; and
a photo detector for receiving reflected light from said optical recording medium;
wherein said objective lens or said lens holder includes a light-blocking section that has spread out on both sides of the tracking direction and that is capable of blocking nonessential light from the said light source proceeding toward said optical recording medium by passing outside the effective diameter of said objective lens. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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Specification