Beam deflector
US6473250B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1999 |
| Grant date | Oct 29, 2002 |
| Priority date | — |
| Expiry date | Sep 15, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B26/0883
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A beam deflector has first and second wedge prisms having refractive indices and geometries which are similar (in the case of the geometry to within arc minutes). The prisms are rotatable about an optical axis O defined by the direction of propagation of the incident light beam, to adjust the angle through which the incident beam is deflected. A third prism has a wedge angle which is greater than that of the first and second prisms by a factor of 2. When the directions in which the first and second prisms refract the beam away from the optical axis are aligned about the optical axis at notional angles of 0° and 90° respectively, and the third prism is aligned with its direction of refractive deviation at a notional angle of 225° about the optical axis, the light beam will pass undeviated through the deflecting device. The provision of the third prism ameliorates the need to match closely the geometries and refractive indices of the first and second prisms, and yet avoids the occurrence of angles through which the beam may not be deflected as a result of insufficiently closely matched prisms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.