Optical head assembly and element holder with positional adjustment
AssigneePioneer Electronic Corporation
InventorShizuo Hirano
Life of this patent
Estimating the term…
Abstract
An optical read/write head assembly for a record disk includes a hollow body member 3, 6 mounting an objective lens 1, a prism 16 and a laser 10. An intermediate plate 20 is mounted to the body by a screw 21 extending through an enlarged bore 23 in the plate to enable its positional adjustment in an X-Y plane. A cylindrical holder 8 extends slidably through a further bore 29 in the plate and through an enlarged bore 36 in the body member, and mounts a quadranted photodiode on its inner end. The holder is axially adjustable in the Z axis direction, to thus enable the centering and focusing of a reflected beam on the face of the photodiode.
Claims6
An optical head assembly for recording and/or reading information on/from a surface of a disk (4), comprising:
- (a) a hollow, cylindrical first holder member (3, 6),
- (b) an intermediate member (20) adjustably mounted to the first holder member for planar movement in X and Y directions relative thereto, and having a Z axis aperture (29) extending therethrough,
- (c) a second holder member (8) extending through the aperture and guided for adjustable, axial, linear movement therein,
- (d) a laser (10) mounted to an inner portion of the first holder member,
- (e) a quadranted photodiode (13) mounted to an inner end of the second holder member,
- (f) a partially reflective prism (16) mounted within the first holder member for directing light emitted from the laser onto the disk surface via a focusing objective lens (1) mounted in an end of the first holder member cylinder, and for directing light reflected from the disk surface onto the photodiode,
- (g) means (21-23) for enabling the adjustment of the intermediate member (20), and attendantly the second holder member and photodiode mounted thereto, in the X and Y directions to a position whereat a reflected beam of laser light is centered on the photodiode, and
- (h) means (28, 30, 31) for enabling the axial adjustment of the second holder member in the Z axis direction to a position whereat the beam of reflected light incident on the photodiode is focused.
Dependencies are inferred from the claim text.