Synchronizing signal generating system
US5059987A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 1990 |
| Grant date | Oct 22, 1991 |
| Priority date | — |
| Expiry date | Apr 5, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04798
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A synchronizing signal generating system for a laser scanner comprises a source for emitting a first laser beam for scanning and a second laser beam for synchronization of scans by the first laser beam, a deflector for causing a scan of a medium by the first laser beam and a scan of a grating by the second laser beam, a converging optical system for converging the second laser beam transmitted through the grating, a light receiving system for receiving the second laser beam converged by the converging optical system and for generating a reference pulse signal, a circuit for controlling the source responsive to the reference pulse signal so as to synchronize a scan timing of the first laser beam and comprising a PLL circuit for generating a synchronizing signal which has a frequency N times a frequency of the reference pulse signal in response to the reference pulse signal and a control circuit for controlling a value of N depending on the recording density, and a driving circuit for driving the source of synchronism with the synchronizing signal depending on input information data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.