Apparatus to transform a single frequency, linearly polarized laser beam into a beam with two, orthogonally polarized frequencies
US4684828A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 12, 1985 |
| Grant date | Aug 4, 1987 |
| Priority date | — |
| Expiry date | Mar 12, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/116
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An electro-optical apparatus transforms a single stabilized frequency, linearly polarized laser input beam (18) from a light source (10) into an output beam (46) having two orthogonal polarization components of different frequency. The input beam (18) is provided to an acousto-optic Bragg cell (20) which is driven by the output of an electrical oscillator (30) which provides the Bragg cell (20) with a frequency stabilized electrical signal (32) comprised of two different frequencies. The Bragg cell (20) transforms the input beam (18) into two intermediate beams (40, 42) having the same linear polarization as the input beam (18) but whose directions of propagation and frequencies differ from the input beam (18) and which are at one-half the intensity of the input beam (18). The Bragg cell (20) output is provided to a birefringent prism (44) which splits the intermediate beams (40, 42) into the two orthogonal polarization components of the output beam (46), at one-half the intensity of the input beam (18 ), and two spurious beams (48, 50) which are eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.