Diode pumped laser using gain mediums with strong thermal focussing
US5907570A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1997 |
| Grant date | May 25, 1999 |
| Priority date | — |
| Expiry date | Oct 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/1673
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A diode pumped laser includes a resonator mirror and an output coupler, defining a laser resonator with a resonator optical axis. A strong thermal lens gain medium with a TEM.sub.00 mode diameter is mounted in the resonator along the resonator optical axis. The dopant level of the gain medium is in the range of 0.01 to less than 0.5 percent. A diode pump source supplies a pump beam to the gain medium in the laser resonator, and produces an output beam with a diameter larger than the TEM.sub.00 mode diameter to reduce thermal birefringence. A power source supplies power to the diode pump source. A polarizing element can be positioned in the resonator, along with a aperture stop The laser operates well over a large range of pump powers. Its slope efficiency in the TEM.sub.00 mode is greater than 40%, with an overall efficiency greater than 25%. One of the gain mediums used is Nd:YVO.sub.4. This material exhibits high gain and a short upper state lifetime. These properties make it attractive in designing a Q-switched laser, or one that is insensitive to optical feedback. Another material is Nd:YAG. The technique of optimizing the pump beam spot size is found to minimize loss due to th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.