Optical beam scanning apparatus
US5214528A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1991 |
| Grant date | May 25, 1993 |
| Priority date | — |
| Expiry date | Sep 10, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/0678
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed are optical beam scanning apparatus and method of the internal drum scanning system, in which optical beams from a light source are made incident on optical beam rotating means such as a trapezoidal prism, and outgoing beams are focussed on the inner face of a cylinder through rotary optical means such as a rotary reflecting element. In the scanning apparatus and method of the present invention, by rotating the trapezoidal prism on the same revolution axis as that of the rotary reflecting element at a revolution speed corresponding to 1/2 of the revolution speed of the rotary reflecting element, beams going out from the trapezoidal prism can be rotated at the same speed as the revolution speed of the rotary reflecting element. According to the present invention having the above structure, even when a plurality of beams are used, crossing of the beams on the inner face of the cylinder can be prevented, and multiple beam scanning becomes possible and recording can be performed at a high speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.