Three color dichroic beamsplitter for separating or combining unpolarized light
US5880889A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1997 |
| Grant date | Mar 9, 1999 |
| Priority date | — |
| Expiry date | Feb 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/143
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A beamsplitter (70) for separating a beam of light (48, 90, 92) into three frequency bands (94, 96, 98) corresponding to a first color (94), a second color (98), and a third color (96) adapted for use with a beam of white light (92). The inventive beamsplitter (70) includes first (78) and second (80) surfaces for reflecting the first color of light (94) and for transmitting the second color of light (98). A third (82) and fourth (84) surface reflect the second color of light (96) and transmit the third color of light (98). A glass support structure (72) supports the first (78), second (80), third (82), and fourth (84) surfaces in a predetermined configuration. The configuration is chosen so that the first color of light (94) is directed in a first direction (94), the second color of light (96) is directed in a second direction (96), and the third color of light (96) is directed in a third direction (96). The support structure (72) includes a first material having a second index of refraction that is sufficiently different than the index of refraction of a surrounding material (86) to minimize undesirable polarization effects. In the illustrative embodiment, the surrounding material…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.