US 5,742,634 A · Picosecond laser

Abstract

A laser system which generates pulses with a duration in the range of about 60 to 300 ps at an energy level of up to a few milli-Joules per pulse (mJ/p) with near diffraction limited beam quality. A laser crystal is pumped (excited) by diode lasers. A resonator having at least two mirror surfaces defines a beam path passing through the laser crystal. The beam path in the resonator is periodically blocked by a first optical shutter permitting pump energy to build up in the laser crystal, except for a short period near the end of each pumping period. While the first optical shutter is open a second optical shutter blocks the light in the resonator except for periodic subnano-second intervals, the intervals being spaced such that at least one light pulse traveling at the speed of light in the resonator is able to make a plurality of transits through the resonator, increasing in intensity by extracting energy from the excited laser crystal on each transit. After the light pulse has built up in intensity, an optical release mechanism releases the pulse from resonator.

Claims30

Dependent claims

A solid state short pulse laser system comprising:

A) a laser crystal;
B) an optical pump arranged to pump said laser crystal;
C) at least two mirror surfaces defining a resonator, said resonator defining a beam path which transits said laser crystal;
D) a first optical shutter installed within said beam path for blocking passage of light in said beam path except for short periods of time, said first optical shutter defining an ON period and an OFF period;
E) a second optical shutter installed within said resonator for blocking the passage of light in said resonator except for periodic sub nanosecond intervals, said intervals being spaced such that during each ON period a light pulse traveling at the speed of light in said resonator is able to make a plurality of transits through said resonator, increasing in intensity on each transit to defined an intensified pulse;
F) an optical release mechanism for periodically releasing intensified pulses from said resonator, said periodically released intensified pulses defining an intensified pulse laser beam.

3 more elements

Dependencies are inferred from the claim text.

Picosecond laser

Life of this patent

Picosecond laser

Life of this patent

Abstract

Claims30