Laser mode locking method and apparatus
US4933944A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 1989 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | Feb 28, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/108
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The disclosure is directed to two embodiments for passive and one embodiment for active mode locking of lasers. The passive systems comprise a GaAs/GaAlAs diode laser (810 nm) pumped Nd:YAG (1064 nm) laser sharing the same optical cavity. A KTP crystal is used to produce a sum of the frequencies of the diode and Nd:YAG laser (460 nm). The KTP crystal and trichroic mirror (with a reflectivity at 810 nm less than the reflectivity at the other two wavelengths) combine to create an effective end mirror reflectivity which increases in accordance with the intensity of the pump laser wavelength (810 nm) to mode lock the system. The active embodiment uses successive sum and difference frequency generation to modulate the reflectivity of a cavity output coupling mirror in a continuous wave dye laser or external cavity diode laser. A KTP crystal is used to sum the frequencies of the 810 nm dye laser and injected pulses from a Nd:YAG (1064 nm) laser which mode lock the dye laser by periodically increasing the reflectivity of its output coupling mirror, the reflectivity of which is responsive to the intensity of light thereon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.