Laser beam recording system
US4212018A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 1979 |
| Grant date | Jul 8, 1980 |
| Priority date | — |
| Expiry date | Jan 15, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04798
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a laser beam recording system employing a rotating polygonal mirror for deflecting a recording light beam and a read-out light beam for synchronization, a linear encoder is used to generate a video clock signal in synchronization with the photoelectric pulse signal obtained through the linear encoder. In the video clock signal generator, a clock signal is divided into 1/n where n is an integral number to provide a reference pulse signal to be compared with the photoelectric pulse signal. The displacement of the phase of the photoelectric pulse signal from the reference pulse signal is detected and is corrected by a phase comparator. Thus, a video clock signal having a frequency of n-times as large as that of the photoelectric pulse signal is generated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.