USA As Represented by Secretary of the Navy

Joseph F Pinto

Leon Esterowitz

Gregory J Quarles

Arthur W Snow

Filbert J Bartoli

James S Shirk

Robert C Stoneman

Steven R Flom

James R Lindle

Michael E Boyle

Richard G Pong

An optical limiter structure which includes a limiter material preferably dissolved in a host. The limiter material is selected from substituted and unsubstituted phthalocyanines, naphthalocyanines, porphyrins, salts of these materials and mixtures thereof, whereas the host is selected from any material which can dissolve the limiter material to at least the extent of 0.1% by weight.

Optical limiter structure and method

An ultraviolet laser system is disclosed for generating an ultraviolet frency in the spectral region between 223 nm and 243 nm by mixing the tunable output of a Ce.sup.3+ :LiCAF laser with the 1064 nm radiation from a Nd:YAG pump laser in a BBO nonlinear crystal.

Solid state ultraviolet laser tunable from 223 NM to 243 NM

A mirrorless, distributed-feedback (DFB), ultraviolet, tunable, narrow-liidth, solid state laser for remote sensing and medical applications is disclosed. Optical pumping in the DFB laser is accomplished using a frequency quadrupled, 10 Hz., Q-switched, Nd:YAG laser operating at 266 nm. The pump beam is diffracted off a grating (2400 grooves per mm.) into two parts. The two beams are subsequently recombined at the side face of the Ce:doped crystal (8 mm.times.8 mm.times.30 mm) at an angle of about 2.theta.(about 81 degrees). The resulting spatially periodic excitation within the Ce-doped gain medium due to the interferring pump beams determines the operating wavelength of the DFB laser.

Mirrorless, distributed-feedback, ultraviolet, tunable,

An ultraviolet solid state laser includes: (a) a laser cavity defined by a et of opposing mirrors, (b) a laser medium disposed in this laser cavity, where this medium includes a LiSrAIF.sub.6 (LiSAF) host material doped with enough cerium ions to produce a longitudinal mode laser emission when this laser medium is pumped; and (c) a source of pumping radiation.

Continuously tunable UV Ce:LiSAF solid state laser

A room-temperature solid state laser for producing an output laser emission t any wavelength within a preselected range of wavelengths is disclosed. In a preferred embodiment, the laser comprises: a pump laser for emitting a CW pump beam at a preselected wavelength; a laser cavity defined by a first reflective element, an output coupler reflective element and a folded mirror disposed between the first reflective element and the output coupler reflective element to form a reflective path thereamong in the laser cavity; a laser crystal disposed in the laser cavity, the laser crystal being responsive to the CW pump beam at the preselected wavelength for producing a CW laser emission within a preselected range of wavelengths when the laser crystal is pumped by the CW pump beam at the preselected wavelength, the folded mirror operating to collimate the CW laser emission in the optical path between the folded mirror and the output coupler reflective element; and a tuning element disposed in the laser cavity between the folded mirror and the output coupler reflective element for tuning the collimated CW laser emission to any wavelength within the preselected range of wavelengths.

Diode-pumped, continuously tunable, 2.3 micron CW laser

A continuous wave modelocked laser is provided which generates output pul having a duration in the picosecond range at a repetition rate in the MHz to GHz ranges. The laser includes a laser cavity defined by spaced, opposed reflective member forming a reflective path therebetween; a host laser crystal disposed in the cavity; an acousto-optic modulator disposed between the host laser crystal and one reflective member for modulating the output of the host laser crystal; and a birefringent filter, disposed in the laser cavity between the host laser crystal and the one reflective member, for tuning the laser emission to any one of a plurality of wavelengths within a range between 1.86 .mu.m and 2.14 .mu.m. A pump source pumps the host laser crystal at a wavelength of substantially 785 nm. A collimating plano-convex lens is disposed so that the planar face thereof faces the laser crystal. A mechanical device adjusts the length of the reflective path by axially displacing the one reflective member in the laser cavity so as to match the cavity round trip time to the second harmonic of the drive frequency of the acoustic-optic modulator.

Two-micron modelocked laser system

A flashpumped, tunable, two-micron, solid state laser is disclosed in which laser spiking is suppressed. The solid state laser comprises: a laser cavity defined by a first reflective element and an output coupler reflective element to form a reflective path therebetween; a laser crystal disposed in the laser cavity, the laser crystal having a host material doped with preselected activator ions sufficient to produce a pulse of laser emission at a desired laser transition wavelength in a range between about 1.9 microns and about 2.1 microns when the crystal is optically excited to produce the laser emission; a pulsed flashlamp for optically exciting the laser crystal to produce a pulse of laser emission at the desired laser transition wavelength; a tuner disposed in the laser cavity between the laser crystal and one of the reflective elements for tuning the laser emission to the desired laser transition wavelength in the range of wavelengths between about 1.9 microns and about 2.1 microns; optical plates oriented at Brewster's angle in the reflective path for suppressing oscillation of undesired wavelengths within the laser cavity; and a nonlinear crystal disposed in the reflective path to enable the laser to emit through the output coupler reflective element a smooth, long pulse of laser emission without spiking at the desired laser transition wavelength.

Suppression of relaxation oscillations in flashpumped, two-micron

A tunable solid state laser for producing a laser emission at any desired w or high laser gain transition in a predetermined range of wavelengths is disclosed. The tunable solid state laser comprises: a laser cavity defined by a first reflective element and an output coupler reflective element to form a reflective path therebetween; a laser crystal disposed in the laser cavity; means for optically exciting the laser crystal to produce a laser emission in the predetermined range of wavelengths; a tunable element disposed in the laser cavity between the laser crystal and one of the reflective elements for tuning the laser emission to any desired laser transition in the predetermined range of wavelengths; and a plurality of optical plates oriented at Brewster's angle in the reflective path in the laser cavity for suppressing oscillation of undesired wavelengths within the laser cavity, the optical plates being transparent to the laser emission over the predetermined range of wavelengths. The tunable solid state laser can further include an aperture disposed in the reflective path in the laser cavity to allow the laser to lase in the laser cavity only at the lowest order spatial transverse mode of the desired wavelength in the predetermined range of wavelengths.

Tunable solid state laser with high wavelength selectivity over a

A room temperature solid state laser for producing a laser emission at a wavelength of substantially 1.96 microns is disclosed. In a preferred embodiment, the laser includes: a laser cavity defined by a plurality of coated reflective elements to form a reflective path thereamong; a laser crystal disposed in the laser cavity and capable of lasing at substantially 1.96 mircons and 2.01 microns when excited; and means for exciting the laser crystal to lase at substantially 1.96 microns and at substantially 2.01 microns. The laser crystal is comprised of a host crystal material capable of accepting Cr.sup.3+ and Tm.sup.3+ ions. Through their respective reflectivities at each of the wavelengths at substantially 1.96 microns and 2.01 microns, the coated reflective elements collectively operate to produce substantial loss in radiation at the wavelength of substantially 2.01 microns and to reflect radiation from the excited laser crystal at a wavelength which will sustain a laser emission only at a wavelength of substantially 1.96 microns.

Growing community of inventors

Laurel, MD, United States of America

Joseph F Pinto