Claims
- 1. An integrated type optical unit for use in an optical pick-up head for reading and/or recording information from and/or on an optical record medium by projecting a light flux emitted from a semiconductor laser onto an optical record medium and by receiving a return beam reflected by the optical record medium by means of a signal detecting photodetector, wherein said semiconductor laser, signal detecting photodetector and a light path separating element for directing the light beam emitted by the semiconductor laser toward the optical record medium and directing the return beam reflected by the optical record medium toward the photodetector are positioned and mounted on a mounting substrate including positioning guides formed by a photolithography.
- 2. An optical head according to claim 1, wherein said mounting substrate is formed by a single crystal silicon wafer.
- 3. An optical unit according to claim 1, wherein the optical unit further comprises a monitoring photodetector for monitoring an amount of light emitted by said semiconductor laser and said mounting substrate includes at least one positioning guide, said monitoring photodetector being positioned and mounted on the mounting substrate by said at least one positioning guide.
- 4. An optical unit according to claim 1, wherein said light path separating element is formed by a multi-image plane parallel plate including first and second triangular prisms made of birefringent materials and joined together, whereby an optic axis of said first triangular prism is set such that said return light flux is divided into ordinary light and extraordinary light having substantially identical intensities, a polarizing film is provided on a surface of the first triangular prism upon which said light flux emitted by the semiconductor laser and return light beam are made incident, and an optic axis of said second triangular prism is set to be inclined by a predetermined angle with respect to the optic axis of the first triangular prism.
- 5. An optical unit according to claim 1, wherein said mounting substrate comprises an upper substrate and a lower substrate made of single crystal silicon, recesses are formed in the lower substrate by anisotropic etching and corresponding openings are formed in the upper substrate by anisotropic etching, said upper and lower substrates being joined to constitute said positioning guides by said recesses and openings.
Priority Claims (4)
Number |
Date |
Country |
Kind |
6-107065 |
May 1994 |
JPX |
|
6-162291 |
Jul 1994 |
JPX |
|
6-171107 |
Jul 1994 |
JPX |
|
6-229597 |
Sep 1994 |
JPX |
|
Parent Case Info
This is a division of application Ser. No. 08/447,208 filed May 22, 1995.
US Referenced Citations (10)
Foreign Referenced Citations (4)
Number |
Date |
Country |
344086A |
Feb 1991 |
EPX |
62-197931 |
Sep 1987 |
JPX |
62-283430 |
Dec 1987 |
JPX |
5314563A |
Nov 1993 |
JPX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
447208 |
May 1995 |
|