Variable lens and birefringence compensator
US4848881A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1987 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Feb 4, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/08072
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Apparatus and method are disclosed for providing a variable lens and birefringence compensator (10) adapted to be used within the resonator cavity of a repetitively pulsed, variable rate, solid state laser. A cylindrical body of optical material (12) having a temperature dependent index of refraction is thermally coupled to heat exchange means (14) surrounded by potting material (16) and a heat sink (18) which adds heat to or extracts heat from the exterior surface of the cylindrical body in order to establish radially dependent thermal and stress gradients within the body. The heat exchange means is supplied power through leads (20) from the same source (22) which excites the excitation mechanism of the solid state laser. Heat is infused into or extracted from the compensator body at the same rate at which the flashtube stimulates the laser rod (24) within the laser cavity defined by resonator mirrors (26, 28). The thermal gradient is used to create a dynamic lens of opposite power to that of the laser rod which corrects beam divergence in the lased output. The stress gradient causes the compensator body to behave like a birefringent substance. The double refracting behavior of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.