Method and apparatus for improved waveplates and suppression of stray light in LCoS kernel applications
US7042610B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 12, 2004 |
| Grant date | May 9, 2006 |
| Priority date | — |
| Expiry date | May 12, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/136277
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Optical components are louvered with a light absorptive material that absorbs stray light rays. The louvers are constructed, for example, using a “black” thin film coating between sheets of glass. The louvered components are placed in an optical path at one or more orientations. In one embodiment, a vertically oriented louvered component and a horizontally oriented louvered component are individually located in a light path to reduce and/or eliminate stray light having either horizontal and/or vertical vector components. Compensated higher order waveplates are constructed from birefringent material by placing two higher order waveplates (a nλ waveplate and a (n+Δ)λ waveplate.) in proximity to each other such that their principle retardation axes are perpendicular. In one embodiment, the higher order waveplates include louvers for stray light suppression.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.