Abstract: A slab waveguide laser which provides efficient operation in predominantly a single mode operation includes a periodic modulation structure positioned between a slab waveguide and one of two cavity mirror reflectors. Alternatively, the periodic modulation structure may be included along the slab face. The periodicity of the periodic modulation structure is determined by the width of the waveguide to ensure that the periodic modulation is coherently self-imaged in one (or more) round trip(s) of the laser cavity. Because of the low loss propagation within the slab waveguide, overall cavity losses are minimized in both the lateral and transverse directions of the slab.

Abstract: A fiber optic connector is described which has an alignment sleeve (70, FIG. 3) for surrounding fiber-holding ferrules (44, 68), wherein the sleeve can deflect to receive a slightly misaligned mating ferrule and wherein the assembly can be readily removed for cleaning. The sleeve is expandable in diameter and is contained in a hood (80) that surrounds the sleeve and that forms front and rear shoulders (82, 84). The hood loosely surrounds the sleeve and the hood is loosely contained in a connector housing passage (34), to facilitate reception of a slightly misaligned mating ferrule. A hood alignment sleeve assembly includes a front body (50) and a rear retention sleeve, or body, with a spring (56) spanning them, the front body being attached to the hood, and the hood shifting forward and rearward with the sleeve. The hood includes a front hood piece (152) forming the front sleeve-abutting shoulder and a rear hood piece (154) forming the rear shoulder.

Abstract: A circuit is provided for driving a second harmonic generator, wherein an unstable optical output caused by a non-linear optical element is stabilized. The optical output value produced by the second harmonic generator is integrated using an integration coefficient selected using a switch according to the level of the optical output value. The integration coefficient may be defined using a first integration coefficient setting resistor connected in parallel with a series connection including a second integration coefficient setting resistor and a negative-polarity-controlled switch.

Abstract: In a high speed optical clock extraction arrangement, an incoming digital signal is divided between two paths (11, 25). The signal on one path (25) is fed direct to a receiver (203), while the signal on the other path (11) is fed to a non-linear optical amplifier (1) which has separate gain and absorbing regions. The non-linear optical amplifier (1) is triggered by the incoming signal to pulsate at a clock frequency contained in the signal, and the resultant strong output clock signal is coupled into the path (25) carrying the incoming signal to the receiver (203). The non-linear optical amplifier (1) can provide a very high frequency clock output as a result of selective modification of the carrier lifetime.

Abstract: A reading magnifier formed by a bundle of juxtaposed longitudinally tapered optical fibers having a viewing end and a flat base end. The flat base end is cut at a bias across the bundle of optical fibers such that a line normal to the flat base end forms an acute angle with the direction of orientation of the optical fibers. The viewing end of the bundle may also be cut at an angle relative to the optical fibers. The reading magnifier provides a cone of light admittance that is skewed at an angle relative to a cylinder normal to the flat base end. The tilted admittance cone may also be achieved by bending the bottom portion of a bundle of tapered continuous optical fibers.

Abstract: The efficiency of an N.times.N waveguide grating router may be increased in many applications by incorporating at least one output waveguide, such as an (N+1).sup.st waveguide, positioned for capturing second order diffraction optical energy from a free-space region in the router. The second order diffraction optical energy is delivered at a wavelength or at wavelengths corresponding to that wavelength or those wavelengths output on a particular associated one of the original N waveguide outputs for the router.

Abstract: A flashlamp-excited dye laser generates a pulsed output beam having a long pulse duration. The laser includes a pulse forming circuit which generates an excitation pulse having an amplitude which generally increases in coordination with the lasing threshold for the flashlamp-excited dye laser. The flashlamp-excited dye laser is driven with the pulse to produce a pulsed output beam of laser radiation of at least 500 microseconds in duration.

Abstract: A source of electromagnetic radiation including an output, means for generating a drive signal derived from a regenerative feedback signal generated from a portion of said output, further characterized in that an electrical signal obtained from said portion of said output is passed through a narrow bandpass filter in generating said regenerative feedback signal, and means for modulating said electromagnetic radiation within the cavity when the modulating means is driven by said drive signal is disclosed together with a method of generating short pulse electromagnetic radiation signals including operating a electromagnetic radiation source having an output, generating a drive signal derived from a regenerative feedback signal generated from a portion of said output, further characterized in that said portion of said output is passed through a narrow bandpass filter in generating said regenerative feedback signal, and, modulating said electromagnetic radiation, said drive signal derived from a regenerative feed

Abstract: A method and system for forming microlens (78) on an optical fiber (60) include optical fiber lensing device (10) having lowering mechanism (18) for inserting optical fiber (60) at a predetermined and controlled speed to a predetermined depth in oil-acid bath having oil layer (62), acid layer (64), and boundary (68) between oil layer (62) and acid layer (64). The next step is to etch optical fiber (60) at boundary (68) by forming meniscus (66) around optical fiber (60) to selectively and controllably form on optical fiber (60) a microlens (78) having a predetermined shape, preferably a hyperbolic shape. The etching includes the steps of first tapering optical fiber (60) to a shape determined by the distance that optical fiber (60) is first inserted into acid layer (64). The etch step further chemically mills microlens (78) on optical fiber (60) to the predetermined shape by controlling the etch time and position of optical fiber (60) relative to boundary (68) for etching optical fiber (60) at boundary (68).

Abstract: A laser oscillator has a casing 10. A cooling medium is supplied from an inlet port 134 to a heat exchanger 8 via a pipe 35, and discharged form it via a pipe 37 and an outlet port 136. The ports 134 and 136 are symmetrically positioned relative to a center line of the casing when seen from upward. An inlet port 340 and an outlet port 342 have a similar positional relation ship thereto.

Abstract: This invention relates to a singlemode laser source tunable in wavelength with a self-aligned external cavity, comprising: a resonant cavity having an output face that is partially reflecting (331) and a retroreflecting dispersive device (31, 39), defining a main collimating axis (351) and a secondary collimating axis (381), an amplifier wave guide (33) placed in position inside the resonant cavity. The retroreflecting dispersive device comprises a plane diffraction grating (31) having dispersion planes and an orthogonal reflecting dihedral (39) whose line of intersection (391)is parallel to the dispersion plane of the diffraction grating containing the collimating axes (351, 352).

Abstract: A laser light generating apparatus has a first light source generating a light beam of a fundamental wavelength, a resonator made up of a plurality of reflection devices having high reflectance with respect to the fundamental wavelength of the light beam and a non-linear optical crystal element located within the resonator and generating a light beam of harmonic when the light beam of the fundamental wavelength is input thereto. Further, the laser light generating apparatus an amplifier element located within the resonator and amplifying the light beam of the fundamental wavelength therein and an energy source for exciting the amplifier element.

Abstract: A new cartridge excimer laser system and method for generating an excimer laser beam using the system are provided. The system utilizes a cartridge (10) which contains a halogen-noble gas mixture (19), electrodes (50, 60) having external electrical connections (30, 40), an assembly (20) for transmitting a laser beam output (400), and an external gas port (90). The cartridge (10) fits onto a receptacle (100) located within a receiving compartment (200) of the laser base (300) of the new system. The cartridge (10) is easily replaced by the system operator and is refurbished by the manufacturer when the gas mixture (19) therein is exhausted.

Abstract: An electrode is formed in a predetermined pattern on one surface of a unipolarized MgO-LiNbO.sub.3 substrate that is a ferroelectric substance and possesses a non-linear optical effect. The substrate is subjected to corona electrical charging by the electrode and a corona wire disposed above another surface of the substrate which is opposite to the electrode-side surface, and hence an electric field is applied to the substrate. When localized domain reversals are created on areas where the electrode faces the substrate, a vessel is attached to the electrode-side surface of the substrate. While a resulting closed space is kept in a vacuum by a vacuum pump but the opposite-side surface of the substrate relative to the electrode-side surface is in a non-vacuum, an electric field is applied to the substrate.

Abstract: An opto-mechanical switch suitable for use in optical telecommunications systems comprises an input port and two output ports interconnected by an optical path, an optical element and an actuation mechanism for moving the optical element relative to the optical path so as to change coupling of light beams between the input port and the output ports. The optical element is supported by a flexible suspension unit comprising a pair of mutually-spaced twin elongate flexures. Each of the pair of flexures is attached at one end to an anchorage and at its other end to a mounting for optical element. The flexures are identical in length and flexibility and are spaced apart in the direction of displacement of the optical element. In use, when the actuator displaces the optical element, the flexures flex in common in the direction of displacement of the optical element. The optical element may be an optical fiber, a mirror, a prism, and so on.

Abstract: In a gas laser (1) with a laser gas circulation path (5) in which a fan (4) conveys the laser gas (6) through a laser discharge space or tube (2) and a cooling system (3a, 3b), the gas throughput is increased by a bypass (8) of the laser discharge space (2). In the bypass may be a filter, cooler and catalyst for treating that portion of the laser gas flowing therethrough. The volume of gas diverted through the bypass may be adjusted to improve the efficiency of the laser.

Abstract: Methods and apparatus for side pumping lasers are disclosed. By pre-collimating radiation emitted by laser diode arrays, the present invention provides transverse mode matching to achieve fundamental, or TEM.sub.00, mode operation in the corresponding (nominally vertical) axis. Optics associated with the resonant cavity additionally redirect energy longitudinally through the gain media, enhancing fundamental mode operation in the (nominally horizontal) other axis as well. With dual forty-watt linear arrays of laser diodes and four longitudinal passes, TEM.sub.00 mode outputs exceeding fifteen watts have been achieved.

Abstract: The design and application of an uncoated sapphire crystal as a beamsplitter and output coupler of a laser resonator includes placing the crystal sufficiently close to the Brewster angle to intercept a beam from a lasing medium in a free electron laser to provide a Fox-Smith type resonator or a Michelson type resonator depending on the optical path through the crystal to enable use of high power lasers in interferometric and optical coupling measurements.

Abstract: The present invention relates to a tuneable ring laser with an output having a fixed, stable linear state of polarization with a fixed and known azimuth. The state of polarization at the output is fixed by compensating for component birefringence of the various ring elements that alter the polarization state and azimuth.

Abstract: A housing in a laser system encloses a cathode and a displaced anode and gases ionizable and reactive chemically when a voltage pulse produces a cathode-anode electrical discharge. Moving air cools the components (capacitors, thyratron and triggering circuitry) for producing the voltage pulses. The laser gas temperature is continuously regulated at a particular value whether or not there is an electrical discharge. The concentration of one of the gases in the chamber is regulated to values alternately on opposite sides of an optimal value to provide an optimal energy in each chemical reaction of the gases. The gases are recirculated as by a fan driven on a shaft by a pair of motors and are filtered during such recirculation. The shaft speed is regulated at a particular value and the motor currents are regulated to be equal. Any ozone formed in a compartment holding the high voltage terminals is purged by passing a neutral gas (nitrogen) through the compartment to the atmosphere.