Optical devices having array detectors with light receiving photo arrays larger than an incident laser beam cross-section
US5566151A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Oct 15, 1996 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13722
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical device has an optical array detector with an array of optical receptors (each receptor is an individual photo detector) that has a greater cross-sectional extent than an impinging light beam. The receptors have respective light receiving areas smaller than the a cross-sectional area of the impinging light beam. A ring lens passes a received light beam to the receptor array. A ring lens refracts a defocused and off-track impinging light beam whereby the optical refractive properties of the ring lens change the cross-sectional form of the received light beam in accordance with status of the light beam. Refraction of the received light beam in the ring lens distorts the beam cross-sectional shape for indicating focus and location errors. Provisions are made for automatic calibration of the impinging beam to a current position of the array detector physical position by the optical device. Optical detection and re-calibration is effected by a digital signal processor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.