Two cavity laser

Claim 2

A laser system comprising: a single laser material; means including an aperture plate having a central aperture and a 100 percent reflecting surface surrounding said aperture to define part of a first optical cavity for said material providing regeneration of radiation of a first oscillating mode reflected by said aperture plate; means defining a second optical cavity for said same laser material providing regeneration of radiation of a second oscillating mode passing through the aperture in said aperture plate; means for coupling out of said system radiation of said first oscillating mode; and means for coupling out of said system radiation of said second oscillating mode whereby distinct first and second output beams of different mode oscillations and the same frequency are provided from said single laser material.

Claim 3

A system according to claim 1, in which said state is positioned to intercept laser radiation from one end of said laser material such that its reflecting surface passes a portion of said radiation back through said laser material; a first end mirror positioned to intercept radiation from the other end of said laser material and reflect at least a portion of said radiation bAck through said material to said reflecting surface of said aperture plate, said means defining a second optical cavity including a second end mirror which is partially transmissive positioned to intercept laser radiation passing through said aperture and reflect a portion of said radiation back through said aperture to said one end of said laser material for further reflection back through said material from said first end mirror and thence back through said aperture to said second end mirror, said second oscillating mode being coupled out of said system through said second end mirror.

Claim 4

A system according to claim 2, in which said first optical cavity includes a third end mirror which is partially transmissive positioned to intercept at least a portion of said first oscillating mode of radiation, said first oscillating mode being coupled out of said system through said third end mirror.

Claim 5

A system according to claim 3, in which said first end mirror is 100 percent reflecting, said aperture plate being positioned between said one end of said laser material and said second end mirror and disposed at a 45* angle with respect to the direction of radiation through said laser material, said third end mirror receiving and returning said first oscillating mode of radiation from said reflecting surface of said aperture plate to define an L shape for said first optical cavity.

Claim 6

A system according to claim 3, including a beam splitter positioned between said one end of said laser material and said third end mirror and disposed at a 45* angle with respect to the direction of radiation through said laser material, said aperture plate being positioned to receive radiation reflected by said beam splitter and return radiation in said first oscillating mode, said second end mirror returning radiation of said second oscillating mode to said beam splitter to define an L shape for said second optical cavity; and a 100 percent reflecting mirror positioned to the side of said beam splitter opposite to that of said aperture plate to return radiation to said beam splitter.

Claim 7

A system according to claim 2, in which said first end mirror is partially transmissive to couple out radiation of said first oscillating mode from said first optical cavity.

Claim 8

A system according to claim 2, in which said radiation of a first oscillating mode includes additional oscillating modes to define a multimode output for the first output beam from said first optical cavity, said radiation of a second oscillating mode comprising a single TEMoo for the second output beam from said second optical cavity.

Claim 9

A system according to claim 7, in which the energy of said first output beam is approximately from 10 to 20 times the energy of said second output beam.