Frequency selective output coupling for lasers

Claim 2

A frequency selective output coupling for coupling the output beams of a plurality of laser resonant cavities into a single output beam, said plurality of laser resonant cavities each including a laser medium, a cavity axis and end reflectors, wherein said laser cavities are positioned in parallel, saiD coupling comprising: partial reflecting means positioned adjacent each of the laser mediums at a selected angle to each cavity axis for coupling energy out in two coaxial oppositely directed beams, and an adjustable reflecting means positioned in one of said beams to reflect it back along itself and back through the partial reflecting means to superimpose said two beams to form a single output beam.

Claim 3

A frequency selective output coupling as set forth in claim 1 wherein: said partial reflecting means comprises a partially reflecting surface within each laser resonant cavity, and said adjustable reflecting means comprises a movable reflector for superimposing the output beams into a single output beam.

Claim 4

A frequency selective output coupling as set forth in claim 2 wherein: each partially reflecting surface is located within each laser resonant cavity at approximately 45* to said cavity axis for coupling energy out in two coaxial oppositely directed beams orthogonal to said cavity axis, and the spacing of said movable reflector from said cavity axis controls the phase of the reflected beam and provides means for mode selection.

Claim 5

A frequency selective output coupling for coupling the output beams of a plurality of laser resonant cavities into a single output beam, said plurality of laser resonant cavities each including a laser medium, a cavity axis and end reflectors, wherein said laser cavities are positioned in parallel, said coupling comprising: a partially reflecting surface within each laser resonant cavity positioned adjacent the laser medium at 45* to the cavity axis for coupling energy out in two coaxial oppositely directed beams, orthogonal to the cavity axis, a movable reflector positioned in one of said beams to reflect it back along itself and back through the partially reflecting surface to superimpose said two beams to form a single output beam, the spacing of the reflector from the cavity axis controlling the phase of the reflected beam and providing means for mode selection, and a piezoelectric transducer upon which said reflector is mounted for providing modulation capability for said output beam by moving said reflector.

Claim 6

A frequency selective output coupling for coupling the output beams of a plurality of laser resonant cavities into a single output beam, said plurality of laser resonant cavities each including a laser medium, a cavity axis and end reflectors, wherein said laser cavities are positioned in parallel, said coupling comprising: a partially reflecting surface within each laser resonant cavity positioned adjacent the laser medium at 45* to the cavity axis for coupling energy out in two coaxial oppositely directed beams, orthogonal to the cavity axis, a movable reflector positioned in one of said beams to reflect it back along itself and back through the partially reflecting surface to superimpose said two beams to form a single output beam, the spacing of the reflector from the cavity axis controlling the phase of the reflected beam and providing means for mode selection, and a piezoelectric transducer upon which said reflector is mounted for providing modulation capability for said output beam by moving said reflector.

Claim 7

A frequency selective method for coupling the outputs of a plurality of laser resonant cavities each including a laser medium, a cavity axis and end reflectors, said method comprising the steps of: partially reflecting a laser beam within each laser resonant cavity at 45* to the cavity axis for coupling energy out of said cavity in two coaxial oppositely directed beams, orthogonal to said cavity axis, and reflecting one of the beams back along itself to superimpose the two beams to form a single output beam.

Claim 8

A frequency selective method for coupling the outputs of a plurality of laser resonant cavities each including a laser medium, a cavity axis and end reflectors, said method comprising the steps of: partially reflecting a laser beam within each laser resonant cavity at 45* to the cavity axis for coupling energy out of said cavity in two coaxial oppositely directed beams, orthogonal to said cavity axis, and reflecting one of the beams back along itself to superimpose the two beams to form a single output beam.

Claim 11

A side mode suppressing optical maser comprising first and second reflective means arranged to form an optical resonator having an axis normal to said means; an active medium disposed within said resonator; said first reflective means comprising a single energy reflector; said second reflective means comprising a three mirror secondary resonator excluding said active medium, whereby said second reflecting means can be arbitrarily small and can have reflectivity of correspondingly narrowband.

Claim 12

A side mode suppressing optical maser comprising first and second reflective means arranged to form an optical resonator having an axis normal to said means; an active medium disposed within said resonator; said first reflective means comprising a single energy reflector; said second reflective means comprising a three mirror secondary resonator excluding said active medium, whereby said second reflecting means can be arbitrarily small and can have reflectivity of correspondingly narrowband.

Claim 13

An optical maser according to claim 7 wherein one mirror of said three-mirrOr secondary resonator has a reflecting surface angled with respect to said axis and facing said active medium and hidden from a second mirror and a third mirror of said three-mirror secondary resonator.