Micromirror structures for orthogonal illumination
US6469821B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2000 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Dec 21, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/904
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A micromirror device having an array of mirrors 802 formed with a jagged leading 804 and trailing 806 edge. The jagged leading and trailing edges eliminate the features that cause the most diffraction-straight edges that are perpendicular to the incident illumination 808. The leading and trailing edges preferably are formed as a series of saw teeth having a 45° angle to the incident illumination 808. Angling the edges relative to the illumination axis greatly reduces the diffraction that would occur from edges perpendicular to the illumination axis. By reducing the diffraction, the jagged leading and trailing edges enable the use of orthogonal illumination which reduces the cost, size, and weight of the associated TIR prism. The number of saw teeth can vary, but the three-tooth pattern provides an optimum mixture of low diffraction and ease of production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.