US 5,329,507 AGranted

Solid state optical disk reader

OwnerJonathan B. Nelson, Neil R. Browninventors

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Abstract

A device that uses a laser beam to access data stored on an optical disk is disclosed. The laser beam is confined in a thin film optical waveguide having electrodes mounted onto the surface of the waveguide. The electrodes are arranged to form a coarse adjustment section, which adjusts the beam's direction to coincide with the data track of the optical disk to be accesses, and an electro-optic focus, which focuses the beam onto the surface of the optical disk. The electrodes are selectivity supplied with voltages from a control circuit. When the electrodes are energized, the index of refraction of the waveguide is altered, causing the beam direction and focus to be adjusted so as to coincide with and become focused onto the data track. After reflection off the data track, the beam impinges upon an array of photodetectors. The photodetectors provide a feedback signal to the control circuit which is used to continually adjust the beam direction and focus as the optical disk is read.

Claims1

Dependent claims

A solid state optical disk reader for accessing data stored on an optical disk comprising:

(a) light source emitting a monochromatic beam in a beam direction;
(b) a waveguide optically coupled to said light source and confining said beam to a defined region;
(c) electro-optic adjustment and focus means for changing the index of refraction of said waveguide solely electrically thereby adjusting the direction of said beam through said waveguide to become radially aligned with and focused on a data track on said disk to be accessed;
including:
an integrated electro-optic adjustment means which electrically deflects said beam in said waveguide and which focuses said adjusted beam upon the surface of said data track;
(d) reflecting means coupled to said waveguide for reflecting said beam from said waveguide to said data track;
(e) detector means for detecting said beam after reflection of said beam from said data track, said detector means responsively issuing a signal;
and
(f) a control circuit receiving said signal from said detector and responsively issuing control signals to said electro-optical adjustment and focus means.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/131,991Filed 4 Oct 1993 · continuation
Priority: 24 Sep 1991
Granted: 12 Jul 1994
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

G11B 7/085
Disposition or mounting of heads or light sources relatively to record carriers: with provision for moving the light beam into, or out of, its…
G11B 7/124
Integrated head arrangements, e.g. with source and detectors mounted on the same substrate: the integrated head arrangements including waveguides
G11B
Information storage based on relative movement between record carrier and transducer