Abstract: The invention deals with a face pumped slab laser in which the slab is of a rectangular configuration, favoring use of an optical resonator cavity capable of producing a rectangular beam of good quality within the cavity. The novel optical resonator cavity, which produces this rectangular beam, is stable on one axis corresponding to the smaller beam dimension and unstable on an axis orthogonal to the first axis corresponding to the larger beam dimension. The result is both high efficiency, excellent power and a good quality output beam is produced.

Abstract: The invention is a nonlinear or bistable optical device having a low switching energy. The invention uses a means responsive to light for generating a photocurrent, a structure having a semiconductor quantum well region, and means responsive to the photocurrent for electrically controlling an optical absorption of the semiconductor quantum well region. The optical absorption of the semiconductor quantum well region varies in response to variations in the photocurrent. A photodiode or phototransistor may be used as the means responsive to light, and may be made integral with the structure having the semiconductor quantum well region. An array of devices may be fabricated on a single chip for parallel logic processing.

Abstract: A Q-switched laser in which the laser cavity contains on one side of the laser rod (1) a mirror (2) and on the other side of the laser rod (1) in sequence a polarizer (4) and an electro-optical cell (5) and first fold-back reflector means (3) to fold-back the beam to a second reflector (6) arranged to direct the beam back to the polarizer (4) to form a loop around the electro-optical cell (5). The mirror (2) is a partial reflector to allow output from the laser rod (1) through the mirror in pulse reflection mode or is a total reflector to allow output from the polarizer (4) in pulse transmission mode.

Abstract: An unpolarized electro-optically Q-switched laser using a laser rod (4), a prism (1) and a Pockels cell (5) between a pair of mirrors (2, 3) wherein the prism (1) is selected to give a low-angle walk-off arranged that when a quarter wave length voltage is applied to the Pockels cell the first pass will be cancelled by an equal and opposite walk-off during the return path.

Abstract: An amplitude modulator for a tunable ring cavity dye laser is disclosed. The modulator is operated in time synchronization with the laser pump and is located assymetrically within the ring to attenuate dye laser pulses in one direction while passing pulses in the opposite direction, thereby producing a mode locked unidirectional travelling wave. The use of a low dispersion electro-optical modulator in a dye laser yields subpicosecond optical pulses with wide tunability.

Abstract: An RF discharge waveguide laser is modulated by an electro-optic modulator positioned in a second optical cavity coupled to a gain cavity containing the waveguide.

Abstract: Reducing the widths of pulses in a beam from a laser by passing the beam through means to rotate the plane of polarization of the beam when a voltage is applied and reflecting the beam back through the means to rotate to a polarizer, the voltage being applied for a length of time equal to the desired pulse width, the portions of the pulses that have passed through the means to rotate when the voltage was applied being deflected by the polarizer into an output beam, the portions of the pulses that have passed through the means to rotate when the voltage was not applied being passed directly through the polarizer without being deflected into the output beam.

Abstract: A uv preionized CO.sub.2 oscillator with integral four-pass amplifier capable of providing 1 to 5 GW laser pulses with pulse widths from 0.1 to 0.5 ns full width at half-maximum (FWHM) is described. The apparatus is operated at any pressure from 1 atm to 10 atm without the necessity of complex high voltage electronics. The reinjection technique employed gives rise to a compact, efficient system that is particularly immune to alignment instabilities with a minimal amount of hardware and complexity.

Abstract: A laser system and method is disclosed which is capable of producing high peak power, high pulse rates, and narrow pulses. The invention comprises an acousto-optic shutter and a frustrated total internal reflectance Q-switch in a unique configuration which allows maximum power to be obtained from the laser device while still achieving high pulse rate and narrow pulse width.

Abstract: An electronically switchable multiwavelength laser system comprises a lasing medium capable of generating a beam having at least two different wavelengths, an anisotropic birefringent component in optical alignment with the medium for refracting the beam into spatially separate polarized rays containing both wavelengths, and another electrically controllable anisotropic electrooptically active element, such as a Pockels' cell, having electrodes aligned with the respective rays and selectively energizable to block either ray to permit the laser to oscillate at the wavelength and polarization of the unblocked ray. The laser system includes highly reflective and partially transmissive mirrors defining the laser cavity and assisting in wavelength discrimination, the birefringent component and Pockels' cell being disposed in series between the lasing medium and the highly reflective mirror.

Abstract: Apparatus (FIG. 2) receives light (11) in an input direction (12) and controls the directions in which portions of it travel through regions (13,14) to emerge (at 15) in an output direction (16) with intensity responsive to the product of two electrical potential differences multiplied together.Electrooptic reflective means (18) comprising two electrodes (19,20), on a region (13) in a waveguide (17), form a first Bragg grating (18) with a direction of Bragg incidence in the input direction (12). Similar means (23) comprising two electrodes (24,25), on a region (14), form a second Bragg grating (23) with a direction of Bragg incidence the same as a direction of Bragg reflection (22) from the first grating.A prism (26) directs light (11) from a laser (27) to enter in the input direction (12) into the electrooptic means (18).

Abstract: A known electro-optic has a semiconductor laser, a temperature sensor for controlling an electrically operated cooler, and an optical fiber end portion anchored close to the laser to receive light from it. Usually the fiber is anchored by a mass of cured epoxy. This invention proposes anchoring the fiber in a mass of fusible alloy which is melted and solidified using a Peltier effect device which is driven with one polarity current to function as a heater and with a reverse polarity current to function as a cooler. Once the package is complete and the laser is operating, the temperature sensor together with the Peltier effect device functioning as a cooler are used to cool the laser.

Abstract: An electro-optically Q-switched cavity-dumped laser is improved by the addition of an injection control laser, so that time jitter is reduced, frequency stability is improved, higher peak circulating power in the Q-switch pulse is achieved, an intracavity grating is no longer required.

Abstract: A single element interposed in a laser resonator cavity provides for AM mode-locking, Q-switching and dumping in a sequential operation in which a Pockels cell or like polarization rotation device is first energized to prevent build-up of radiation in a laser cavity, is then switched to provide for mode-locking by energization with a periodically varying signal, and is finally energized to dump a single mode-locked pulse. The sequential operation permits the use of a single electro-optic element and a single pair of electrodes. Q-switching, mode-locking and dumping are accomplished utilizing the same physical effect in the crystal, e.g., polarization rotation.

Abstract: Electro-optical apparatus for modulating a randomly polarized light beam is disclosed. The apparatus includes an electro-optical cell and a plurality of optical elements configured to polarize the randomly polarized light beam into two light beam components and to guide the light beam components along two respectively corresponding sets of optical paths, a portion of each set of optical paths passing colinearly through a predetermined axis of the electro-optical cell. Each set of paths are combined to reform an associated portion of the randomly polarized light beam which is exited at a corresponding exit surface of the apparatus, the reformed exited portion, in each case, being a function of the energization of the electro-optical cell. In one application, the electro-optical apparatus is disposed in the optical cavity of a laser system and operative therein as a Q modulator wherein the Q of the laser cavity is dependent on the energization level of the electro-optical cell.

Abstract: The optical beam scanner employs novel utilization of the well known Stark effect. By means of an external applied voltage, a change in the index of refraction of an optical medium is produced. This produces a bending effect on light transmitted through the medium. Varying the applied voltage can be used to vary the refractive index, or a refractive index gradient may be produced by providing a gradient in the applied field, to produce no moving parts scanning of the optical beam.