Dynamic power control for an external cavity stabilized laser diode in a holographic scanner
US4699446A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1985 |
| Grant date | Oct 13, 1987 |
| Priority date | — |
| Expiry date | Mar 18, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/0687
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A dynamic power control for an external cavity stabilized laser diode adapted for use with a Raster Output Scanner employing a photodiode to convert light emitted from the rear facet of the diode internal cavity to an electrical signal, and a comparator for comparing the light intensity signal with a reference signal and adjusting the drive current input to the diode to maintain diode output pwer constant. In a second embodiment, diode power is taken from the zero order beam at the external cavity transmissive wavelength selecting grating, in a third embodiment from the external cavity output beam, and in a fourth embodiment, from the zero order beam that passes through the holographic disc facets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.