Method and apparatus for efficient operationof a solid-state laser optically pumped by an unstable resonator semiconductor laser

Claim 3

The method of claim 1 in which the unstable resonator semiconductor laser comprises a material selected from AlGaAs, AlGaInP, InGaAsP, and ZnSe.

Claim 4

The method of claim 1 in which the solid-state lasant is fabricated from a chromium-doped fluoride crystal of Cr 3+ :XYZF 6 composition wherein X is selected from Li + , Na + , K + , and Rb + , Y is selected from Ca 2+ , Sr 2+ , Ba 2+ , Cd 2+ , and Mg 2+ , and Z is selected from Al 3+ , Ga 3+ , and Sc 3+ .

Claim 5

The method of claim 1 in which the solid-state lasant is doped with a rare earth ion selected from neodymium, holmium, erbium, and thulium.

Claim 6

The method of claim 1 in which the bright output light comprises primarily red light.

Claim 7

The method of claim 1 in which the unstable resonator semiconductor laser includes: a resonator having a length, a virtual point source in a lateral plane, and a real point source in a transverse plane; and a mirror having a radius of curvature that forms one end of the resonator, the resonator length and mirror radius of curvature selected so that an optical field propagating within the high-power semiconductor laser experiences greater than unity lateral magnification and so that the optical field has a lateral divergence angle originating from the virtual point source and a transverse divergence angle originating from the real point source that are substantially equal, thereby to provide the optical output with a high degree of lateral and transverse spatial coherence.

Claim 10

The method of claim 7 in which the unstable resonator semiconductor laser generates an optical pumping light of a power of greater than about 0.1 W.

Claim 11

The method of claim 7 in which the unstable resonator semiconductor laser comprises a material selected from AlGaAs, AlGaInP, InGaAsP, and ZnSe.

Claim 12

The method of claim 7 which the solid-state lasant is doped with a rare earth ion selected from neodymium, holmium, erbium, or thulium.

Claim 13

The method of claim 7 in which the solid-state lasant is fabricated from a chromium-doped fluoride crystal of Cr 3+ :XYZF 6 composition wherein X is selected from Li + , No + , K + , and Rb + , Y is selected from Ca 2+ , Sr 2+ , Ba 2+ , Cd 2+ , and Mg 2+ , and Z is selected from Al 3+ , Ga 3+ , and Sc 3+ .

Claim 14

The method of claim 7 in which the bright output light comprises primarily red light.

Claim 15

A high-power unstable resonator semiconductor laser for generating optical output, comprising: a resonator having a length, a virtual point source in a lateral plane, and a real point source in a transverse plane; and a mirror having a radius of curvature that forms one end of the resonator, the resonator length and mirror radius of curvature selected so that optical field propagating within the high-power semiconductor laser experiences greater than unity lateral magnification and so that the optical field has a lateral divergence angle originating from the virtual point source and a transverse divergence angle originating from the real point source that are substantially equal, thereby to provide optical output having a high degree of lateral and transverse spatial coherence.

Claim 16

A high-power unstable resonator semiconductor laser for generating optical output, comprising: a resonator having a length, a virtual point source in a lateral plane, and a real point source in a transverse plane; and a mirror having a radius of curvature that forms one end of the resonator, the resonator length and mirror radius of curvature selected so that optical field propagating within the high-power semiconductor laser experiences greater than unity lateral magnification and so that the optical field has a lateral divergence angle originating from the virtual point source and a transverse divergence angle originating from the real point source that are substantially equal, thereby to provide optical output having a high degree of lateral and transverse spatial coherence.

Claim 17

The unstable resonator semiconductor laser of claim 13 that generates an optical output of a power of greater than about 0.1 W.

Claim 18

The unstable resonator semiconductor laser of claim 13 further comprising a material selected from AlGaAs, AlGaInP, InGaAsP, and ZnSe.

Claim 19

The unstable resonator semiconductor laser of claim 13 which the optical output primarily comprises red light.

Claim 20

The unstable resonator semiconductor laser method of claim 13 in which the solid-state lasant is fabricated from a chromium-doped fluoride crystal of Cr 3+ :XYZF 6 composition wherein X is selected from Li + , Na + , K + , and Rb + , Y is selected from Ca 2+ , Sr 2+ , Ba 2+ , Cd 2+ , and Mg 2+ , and Z is selected from Al 3+ , Ga 3+ , and Sc 3+ .

Claim 21

An unstable resonator semiconductor laser-pumped, solid-state laser, comprising: a solid-state resonator cavity having a first optic axis and having a rear mirror and an output mirror positioned about the first optic axis such that the mirrors form ends of the optical resonator cavity; a solid-state lasant positioned about the first optic axis and between the rear mirror and the output mirror, the solid-state lasant having an absorption bandwidth and a mode volume; an unstable resonator semiconductor laser having a second optic axis and positioned so that the second optical axis is substantially coaxial with the first optic axis, the unstable resonator semiconductor laser also having an emission wavelength that is well-matched to the absorption bandwidth of the solid-state lasant; and a coupling system to efficiently collect optical output from the unstable resonator semiconductor laser and subsequently guide the optical output into the solid-state lasant mode volume.

Claim 22

An unstable resonator semiconductor laser-pumped, solid-state laser, comprising: a solid-state resonator cavity having a first optic axis and having a rear mirror and an output mirror positioned about the first optic axis such that the mirrors form ends of the optical resonator cavity; a solid-state lasant positioned about the first optic axis and between the rear mirror and the output mirror, the solid-state lasant having an absorption bandwidth and a mode volume; an unstable resonator semiconductor laser having a second optic axis and positioned so that the second optical axis is substantially coaxial with the first optic axis, the unstable resonator semiconductor laser also having an emission wavelength that is well-matched to the absorption bandwidth of the solid-state lasant; and a coupling system to efficiently collect optical output from the unstable resonator semiconductor laser and subsequently guide the optical output into the solid-state lasant mode volume.

Claim 23

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which the unstable resonator semiconductor laser is of a high-power type.

Claim 24

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which the solid-state lasant is fabricated from a chromium-doped fluoride crystal of Cr 3+ :XYZF 6 composition wherein X is selected from Li + , Na + , K + , and Rb + , Y is selected from Ca 2+ , Sr 2+ , Ba 2+ , Cd 2+ , and Mg 2+ , and Z is selected from Al 3+ , Ga 3+ , and Sc 3+ .

Claim 25

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which optical output power generated by the unstable resonator semiconductor laser is collected and focused by a lens system to form an optical pumping beam whose volume substantially matches the solid-state lasant mode volume.

Claim 26

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which the optical pumping beam substantially matches the solid-state lasant mode volume to produce TEM 00 optical mode output from the solid-state resonator cavity.

Claim 27

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which the unstable resonator semiconductor laser generates an optical pumping beam, and the optical pumping beam and solid-state lasant mode volume have relatively small radii to facilitate laser operation at a low threshold of optical power output from the unstable resonator semiconductor diode laser.

Claim 28

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which the solid-state lasant is a doped with a rare earth ion selected from a neodymium, holmium, erbium, and thulium.

Claim 29

The unstable resonator semiconductor laser-pumped, solid-state laser of claim 18 in which unstable resonator semiconductor laser comprises AlGaAs and in which the solid-state lasant comprises a neodymium-containing lasant crystal.

Claim 30

The unstable resonator semiconductor laser-pumped, solid-state laser system of claim 18 in which the unstable resonator semiconductor laser includes: a resonator having a length, a virtual point source in a lateral plane, and a real point source in a transverse plane; and a mirror having a radius of curvature that forms one end of the resonator, the resonator length and mirror radius of curvature selected so that an optical field propagating within the high-power semiconductor laser experiences greater than unity lateral magnification and so that the optical field has a lateral divergence angle originating from the virtual point source and a transverse divergence angle originating from the real point source that are substantially equal, thereby to provide the optical output with a high degree of lateral and transverse spatial coherence.