System and method for image adjustment in an optical projection system
US4868668A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1987 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Nov 13, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method are provided for controlling a characteristic of an optical image generated by a video projection system of the type wherein illumination light is passed through a polarizing means and then directed to a light modulation device which receives a light image and provides an polarization modulated optical image as outgoing light, the outgoing light being passed through a projection lens to display the optical image. According to the present invention, a portion of the outgoing light is sampled and the sampled portion is directed to a detector which detects characteristics of the outgoing light. The detected characteristics are then compared with the corresponding desired characteristics exhibited by a test pattern image. The differences between the detected characteristics and the desired characteristics are measured and the measured differences are utilized to generate correction factors for controlling the outgoing light such that the outgoing light exhibits the desired characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.