Image forming apparatus
US6021223A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 31, 1997 |
| Grant date | Feb 1, 2000 |
| Priority date | — |
| Expiry date | Oct 31, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2225/32
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An image H(x, y) for displaying a target image G(x, y) is displayed on a liquid-crystal display panel and illumination light from an illumination light source is made to pass therethrough to form an image on a PALSLM. Read light h.nu. is radiated to the PALSLM and a phase-modulated light image .alpha.(x, y) read out of the PALSLM is subjected to Fourier transform by a lens. A phase contrast filter gives a predetermined phase shift to only the zero-order light component of Fourier light image .alpha..sub.f (x, y). The phase-shifted light image is subjected to inverse Fourier transform by a lens to project an output image O(x, y) to an output plane. A light image O'(x, y) branched by a beam sampler is picked up by a pickup device and an evaluation value calculating unit evaluates conformity between the image O(x, y) and the image G(x, y). A control unit performs feedback control of optical characteristics of the illumination light source, PALSLM, and phase contrast filter, based on the evaluation result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.