Shared multi-wavelength laser resonator with gain selected output coupling

Patent metadata

Field	Value
Publication number	US-2016056605-A1
Application number	US-201514827549-A
Country	US
Kind code	A1
Filing date	Aug 17, 2015
Priority date	Aug 22, 2014
Publication date	Feb 25, 2016
Grant date	—

Abstract

The present invention provides improved laser beam quality with fewer parts than the current method demands and decreasing the transmit aperture, said apparatus comprising: two or more independently pumped gain modules, two or more pump diodes, a polarizing waveplate, non-linear optical crystals, and a passive Q-switch.

First claim

What is claimed is:

1 . A shared multi-wavelength laser resonator with gain selected outcoupling, said laser resonator comprising:
first and second independently pumped gain modules defining a lasing plane; first and second pump diodes positioned in the lasing plane, defining proximal and distal ends of said lasing plane, respectively, wherein said first pump diode is in optical communication with said first independently pumped gain module and wherein said second pump diode is in optical communication with said second independently pumped gain module; at least one polarizing waveplate positioned in the lasing plane, adjacent said second independently pumped gain element, opposite said second pump diode, wherein said polarizing waveplate is in optical communication with said second independently pumped gain modules; at least one polarizer positioned in the lasing plane and configured to act as a polarizer at both 1 μm and 1.5 μm; a plurality of non-linear optical crystals positioned in the lasing plane, adjacent said first independently pumped gain element, opposite said first pump diode, wherein said plurality of non-linear optical crystals are in optical communication with said first independently pumped gain module and oriented to convert only S-polarized light; and a passive Q-switch positioned in the lasing plane between said non-linear optical crystals and said first independently pumped gain element; wherein said system is capable of allow for output selection by choosing between the pump diodes.

2 . The lasing apparatus of claim 1 wherein output is selectable between 1 μm and 1.5 μm.

3 . The lasing apparatus of claim 1 wherein said polarizer acts as both a high reflector for S polarized 1.5 μm light and a polarization outcoupler for P polarized 1 μm light.

4 . The lasing apparatus of claim 1 wherein said waveplate is an adjustable quarter-waveplate to provide 1 μm polarized output.

5 . The lasing apparatus of claim 1 wherein said Q-switch is a passive Q-switch.

6 . The lasing apparatus of claim 5 wherein any path saturation of the passive Q-switch is adjusted by load balancing between said plurality of non-linear optical crystals.

7 . The lasing apparatus of claim 1 wherein said gain modules are pumped in a complimentary manner to induce a constant net thermal lens of the resonator.

8 . The lasing apparatus of claim 1 wherein said waveplate is configured to impart appropriate polarization rotation to enter a parallel oscillation state.

9 . The lasing apparatus of claim 1 wherein said waveplate is configured to impart appropriate polarization rotation to enter a senkrecht oscillation state.

10 . The lasing apparatus of claim 1 wherein the wavelength of laser radiation emitted by the system may be controlled through frequency conversion, enabled by the non-linear optical crystals.

11 . The lasing apparatus of claim 1 wherein said Q-switch is comprised of an ion-doped crystal.

12 . The lasing apparatus of claim 11 wherein said ion-doped crystal is Cr:YAG.

13 . The lasing apparatus of claim 1 wherein said first gain element comprises dual high-reflection (HR) coatings adjacent said first pump diode.

14 . The lasing apparatus of claim 13 wherein said first pump diode is a high-power, quasi-continuous wave light source type pump diode.

15 . The lasing apparatus of claim 14 wherein said second gain element comprises a single HR coating adjacent said second pump diode.

16 . The lasing apparatus of claim 15 wherein said second pump diode is a high-power, quasi-continuous wave light source type pump diode.

17 . The lasing apparatus of claim 1 wherein said gain elements are comprise Nd:YAG.

18 . The lasing apparatus of claim 1 wherein said non-linear optical crystals may be used as frequency doublers, providing second harmonic generation.

19 . The lasing apparatus of claim 1 wherein said non-linear optical crystals may be used as optical parametric oscillators.

20 . The lasing apparatus of claim 1 wherein said laser operates in the 1530 to 1620 nm spectral range, resulting in a raised eye-retina damage threshold as compared to 1064 nm lasers.

Assignees

• Bae Sys Inf & Elect Sys Integ

Inventors

• Mccarthy John C

Classifications

• H01S3/09415

  the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping · CPC title

• H01S3/113

  using intracavity saturable absorbers · CPC title

• H01S3/109

  Frequency multiplication, e.g. harmonic generation · CPC title

• H01S3/1312

  by controlling the optical pumping · CPC title

• H01S3/08072

  Thermal lensing or thermally induced birefringence; Compensation thereof · CPC title