Laser arrangement for creating a stable pulse with short pulse spacings

Claim 2

A laser arrangement for creating a stable pulse with short pulse spacings, coMprising: an optical resonator; an active laser medium disposed in said optical resonator; a modulator disposed within said optical resonator on one side of said active laser medium; and a mode selector disposed within said optical resonator on the other side of said active laser medium, said mode selector including an optical filter for a mode group, said optical filter being an interferometer having transmission ranges with a frequency spacing Delta gamma of an integral multiple of the frequency spacing of the axial mode.

Claim 3

A laser arrangement according to claim 1, comprising an optical system for filtering the light which is reflected from said interferometer, said optical system arranged between said active laser medium and said interferometer.

Claim 4

A laser arrangement according to claim 1, wherein said modulator is a phase modulator operating at a frequency which is greater than gamma 1.

Claim 5

A laser arrangement according to claim 1 wherein said modulator is an amplitude modulator operating at a frequency which is greater than gamma 1.

Claim 6

A laser arrangement according to claim 1 comprising an external frequency generator connected to and controlling said modulator.

Claim 7

A laser arrangement according to claim 1, wherein said modulator is coupled to and controlled by the emitted laser beam.

Claim 8

A laser arrangement according to claim 1 wherein said modulator includes light entry and light exit surfaces which are inclined at the Brewster angle.

Claim 9

A laser arrangement according to claim 1, comprising means for changing the resonator length for an automatic matching of the frequencies of the axial modes with a maxima of the transmission ranges of the interferometer.

Claim 10

A laser arrangement according to claim 8 wherein said optical resonator includes a pair of spaced mirrors, and comprising a first piezoelectric disc secured to one of said mirrors for receiving a direct voltage to effect a non-periodic change of resonator length, a second piezoelectric disc connected to said first piezoelectric disc for receiving an alternating voltage to effect automatic frequency matching of the frequencies of the axial modes with the maxima of the transmission ranges of the interferometer.

Claim 11

A laser arrangement according to claim 9 comprising an external frequency generator having a constant frequency connected to said second piezoelectric disc, an optical-electrical receiver disposed outside of said resonator for receiving the laser beam and demodulating the emitted radiation, a filter connected to said optical electrical receiver for passing the frequency of said frequency generator, and a control unit connected between said filter and said first piezoelectric disc for changing the direct voltage applied to said first piezoelectric disc in response to receipt of said frequency via said filter.