On-line laser alignment system for three dimensional display
US5867152A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1996 |
| Grant date | Feb 2, 1999 |
| Priority date | — |
| Expiry date | Mar 14, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N13/398
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A 3D display having a closed loop feedback system dynamically adjusting the scanning pattern of laser beams on-line to maintain pointing errors of all scanned images to a specified tolerance. A predetermined alignment pattern, preferably a matrix of dots with known coordinates, is periodically injected into the image data path, preferably during non-display periods. A grid is disposed on each of two mirrors which enter into two separate light paths and are scanned. The mirrors reflect the laser beams from the grid to an optical sensor for each beam, each sensor connected to an A/D converter and producing an output proportional to the intensity of the reflected light. The sensor output is an analog function of the light intensity impinging thereon. The digitized values are stored in a grid buffer which accumulates an entire intensity pattern of grid points. The the intensity data is collected for offset and gain beams separately and the x and y centroid is computed for the gain and offset grid and used to compute adjustment values for the offset, gain and power intensity of the normal data values sent to the optics. A reference intensity sets the nominal value to which the loop corr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.