Laser scanner with beam transmissivity control
US4959664A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1988 |
| Grant date | Sep 25, 1990 |
| Priority date | — |
| Expiry date | Aug 26, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K15/1219
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A light amount correcting interference membrane having almost constant thickness and characteristic for increasing transmissivity corresponding to an increase of incidence angle of a laser beam is provided on a scanning light path extending from a rotary optical deflector to a recording medium in a scanning optical system. The laser beam deflected by the rotary optical deflector for scanning the recording medium is transmitted through the light amount correcting interference membrane wherein the scanning velocity of the laser beam reaching the peripheral portion of the recording medium is faster than that of the laser beam reaching the central portion, and an incidence angle becomes large and transmissivity becomes high.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.