US 2005/0088949 A1 · Exposure apparatus of an optical disk master, method of exposing an optical disk master and pinhole mechanism

Abstract

An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam obtained based on the laser beam of the laser source and an objective lens for focusing the recording laser beam on an optical disk master, has a lens system provided between the laser source and the deflector, which has a first lens for focusing the laser beam and a second lens for adjusting the focused laser beam to a desired beam diameter; and a pinhole placed at a practical focal position of the lens system.

Claims6

Dependent claims

An exposure apparatus of an optical disk master having a laser source, a deflector for deflecting a recording laser beam based on the laser beam of said laser source and an objective lens for focusing said recording laser beam on an optical disk master, comprising:

a liquid crystal plate provided between said laser source and said deflector;
a parallel flat plate provided between said deflector and said objective lens for branching said recording laser beam;
a photodetector that detects reflected light from said parallel flat plate;
and
adjusting means of adjusting a voltage applied to said liquid crystal plate based on information on wavefront fluctuation of said recording laser beam detected by said photodetector.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

10/975,605Filed 28 Oct 2004

Priority

JP 2001-19815329 Jun 2001

Published

28 Apr 2005

Term ends

Not estimatedThe source records don’t support an estimate.

Classification4 codes

G11B 7/261
Apparatus or processes specially adapted for the manufacture of record carriers: preparing a master, e.g. exposing photoresist, electroforming
G11B 7/128
Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for…
G11B 7/1378
Lenses: separate aberration correction lenses; Cylindrical lenses to generate astigmatism; Beam expanders
G11B
Information storage based on relative movement between record carrier and transducer

Exposure apparatus of an optical disk master, method of exposing an optical disk master and pinhole mechanism

Life of this patent

Exposure apparatus of an optical disk master, method of exposing an optical disk master and pinhole mechanism

Life of this patent

Abstract

Claims6