Optical signal reading device
US4730899A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 1983 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Oct 4, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical signal reading device comprising a laser light source (101), an objective (107) slidable in the direction of the optical axis which is at right angles to the disc surface of a disc-like record carrier, a light detector (110) for receiving the reflected light coming from the disc surface via the objective, and a beam splitter (104) comprised of a single optical part disposed between the light source (101), light detector (110), and objective (107). The splitter has a pair of reflecting surfaces disposed approximately parallel to each other to ensure that the incident light from the light source (101) and the reflected light guided to the light detector (110) are parallel and opposite to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.