Eyesafe laser system using transition metal-doped group II-VI semiconductor as a passive saturable absorber Q-switch
US5832008A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1997 |
| Grant date | Nov 3, 1998 |
| Priority date | — |
| Expiry date | Jan 24, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/164
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An eyesafe laser system includes a Q-switch crystal formed of a semiconductor host material having noncentrosymmetric tetrahedral substitutional sites doped with transition metal ions in concentrations from about 0.001 to about 0.10 atomic percent, which functions as to be a saturable absorber of light at eyesafe wavelengths with a relatively long relaxation lifetime. Co.sup.2+ :ZnSe has been demonstrated to have advantageously high absorption cross section and advantageously high relaxation lifetime at both 1.54 .mu.m (Er:glass laser) and 1.6 .mu.m (Er:YAG laser). Other candidate host materials include other zinc chalcogenides, cadmium chalcogenides and zinc oxide. The resultant Q-switch does not require additional focusing optics inside the cavity and has a saturation fluence which is approximately one order of magnitude less than other state of the art saturable absorbers in the "eyesafe" wavelength region, thereby permitting substantially faster Q-switch bleaching, lower thermal loads, and less potential for damage than was hitherto possible.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.