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 semiconductor laser having a light amplifying diode heterostructure with a flared gain region in an external resonant cavity. The flared gain region has a narrow aperture end which may be coupled to a single mode waveguide and a wide output end. A light emitting surface of the heterostructure proximate to the wide end of the flared gain region is partially reflective and combines with an external reflector to form a resonant cavity that is effectively unstable. The intracavity light-emitting surface proximate to the narrow aperture end is antireflection coated. The external reflector may be a planar mirror or a grating reflector. A lens or an optical fiber may couple the aperture end of the flared gain region to the external reflector. Frequency-selective feedback is provided by orienting the grating reflector or providing a prism in the cavity in front of the external planar mirror. Other filtering elements may also be placed in the external cavity.

Abstract: A semiconductor laser is provided which is capable of generating a train of ultrashort light pulses with an ultrahigh repetition frequency and which is useful in optical communications and optical information processing. The semiconductor laser is a mode-locked semiconductor laser which has two resonator cavities which are formed by two facets and a distributed feedback structure between these two facets. The length of the resonator cavity formed between one facet and the distributed feedback structure is 1/m (where m is an integer) of the length of the resonator cavity formed by the other facet and the distributed feedback structure. A saturable absorption region and a high-frequency modulation region are provided within the longer of the resonator cavities. By making the high-frequency modulation frequency be equal to the round trip frequency of the light within the longer resonator cavity, mode-locked operation is achieved.

Abstract: The invention is for a new type of an efficient and compact laser system, based on semiconductor gain medium, which produces high peak power.

Abstract: The optical design of a laser resonator smooths out the intensity beam profile of the generated laser beam and prevents the formation of "hot-spots." The active laser resonator containing the active laser medium is optically coupled to a free space passive optical resonator to provide mixing and filtering of the spatial modes.

Abstract: A laser is disclosed whose resonant cavity includes a back facet of a semiconductor gain element as one mirror and a passive resonator as part of a second mirror. Appropriate optics are provided for a round-trip path within the resonant cavity that avoids double-passing the passive resonator so that intracavity losses are reduced and more power is fed back to the gain element, which is the active medium of the laser. By ensuring a high percentage feedback of the radiation to the semiconductor gain element, amplitude stable operation can be achieved while locking the frequency of the gain element to the passive resonator. By providing both frequency and amplitude stable operation, fluctuation of the circulating power in the passive resonator is minimized and, therefore, can be usefully employed for many applications.

Abstract: A semiconductor laser oscillator structure and method is described having a tapered gain region in one-half of a laser cavity and a confocal oscillator region in another half of the cavity. An aperture is formed between two pairs of cavity spoilers located between the two cavity halves. One pair of spoilers is provided for receiving light which is reflected off of an output facet back into the semiconductor and removing it from the gain region. The other pair of spoilers removes light reflected from a curved mirror surface formed at the end of the other laser cavity half.

Abstract: A wavelength-varying multi-wavelength optical filter laser using a single pump light source is disclosed.

Abstract: A semiconductor device includes a chip, a laser element formed on the chip and a heating element formed on the chip. The laser element is driven to emit a laser beam upon light-on of a laser. Upon light-off of a laser, switching is made so that the heating element is driven so as not to emit the laser beam in the normal laser beam emission direction by the laser element.

Abstract: A mode locked as a seed source for a solid state regenerative amplifier system is disclosed. The system includes components for forming an external cavity laser with a semiconductor amplifier, exciting and mode locking the cavity laser to emit optical pulses with a linearly time varying optical frequency, collecting and collimating the optical pulses, isolating the optical pulses and amplifying the optical pulses for a selected application. The selected applications include but are not limited to medical imaging, fuel diagnostics, ultrafast spectroscopic measurements, network synchronization, distributed optical clock network, electro-optic sampling, timing Jitter reduction, a source for inducing nonlinear optical effects, and optical time domain relectometry. A mount mechanism support for an optic system is also disclosed.

Abstract: A tunable laser system having a wide tunable range, and narrow line widths, achieves relatively high output powers. The tunable laser system includes a master optical parametric oscillator which generates a seed beam, and a power optical parametric oscillator which is responsive to the seed beam to generate a narrow line width, high power output beam. The master OPO and power OPO comprise gain media consisting of BBO, tunable over a range from about 400 nanometers to more than 2000 nanometers. The master OPO includes line narrowing elements, such as a tunable grating, which limits the line width of the output beam to less than one wave number (centimeter.sup.-1). Pump energy is supplied to the master OPO and power OPO using a Nd:YAG laser with a harmonic generator, so that the second, third, or fourth harmonics of the primary 1064 nanometer line of YAG can be used to pump the BBO crystals. The power OPO may be an unstable resonator.

Abstract: Plural planar optical devices are simultaneously pumped by a single pumping source. Various arrangements for accomplishing such pumping are disclosed. By utilizing these arrangements, the topology and routing of integrated arrays including optical devices are simplified.

Abstract: A phased array of semiconductor laser elements is provided in which the percentage of light which propagates into different diffractive orders is modified by an optical element. The diode laser includes a body of a semiconductor material having an active region therein which is adapted to generate radiation and emit the radiation form a surface of the body, and separate reflecting mirrors at opposite sides of the active region with at least one of the mirrors being partially transparent to the generated light to allow the light generated in the active region to be emitted therethrough. The optical element may take the form of a modification in the arrangement of the semiconductor laser elements, or an array of microprisms, or an external mirror to modify the percentage of light which propagates into different diffractive orders.

Abstract: One end of semiconductor laser 1 is coated an antireflection film 1A. And, the external resonator is constructed with a diffraction grating 2 and an external reflective mirror 4. Additionally, a beam splitter 3 is provided between the diffraction grating 2 and the external reflective mirror 4. An output light from antireflection film 1A of semiconductor laser 1 is transformed to a parallel light by the convex lens 5A, and is supplied to the beam splitter 3. The parallel light 13A changes a light path thereof at beam splitter 3, and is then supplied to the external resonator. A wavelength of the parallel light 13A is determined by the diffraction grating 2, so that the light has a selected wavelength, and a phase which is matched with a phase condition of the external resonator. A portion of the resonated light is reflected by the beam splitter 3, and is fed back to the semiconductor laser 1 via convex lens 5A, as a reflected light.

Abstract: A micro gas laser that provides a very high power to size or weight ratio by including a laser array featuring common optics and common discharge structures. The gas laser includes a laser housing enclosing a supply of laser gas and elongated first and second electrodes. The electrodes are parallel to each other and form a rectangular discharge section between them. Two elongated bore separators extend between the first and second electrodes to divide the discharge section into the three elongated resonator cavities. The bore separators are thin ceramic wafers that electrically isolate the resonator cavities from each other, but retain sufficient thermal conductivity to provide efficient diffusion cooling. The gas laser includes means to apply an electric field between the electrodes sufficient to create a laser beam in each of the three resonator cavities.

Abstract: The invention increases the tuning range of a laser by altering the output coupler reflectivity. In a first embodiment of the invention, the tuning range of an external cavity laser is increased by applying a substantially spectrally flat reflective coating to the front facet of a semiconductor laser which has higher reflectivity than the uncoated front facet. In addition to increasing the tuning range, the increased reflectivity of the front facet reduces the laser threshold current for all laser wavelengths. In a second embodiment of the invention, various complex coatings were applied to the output coupler to generate reflective characteristics that change according to wavelength. The complex coatings enhance reflectance at the edges of the laser tuning curve without adversely affecting the output power at the center wavelengths. This further increases the tuning range of the laser while simultaneously maintaining high output power for each selected output wavelength.

Abstract: The present invention is directed to a method and apparatus for fabricating a dual beam semiconductor laser, wherein the laser includes first and second semiconductor laser dies respectively affixed to one another while separated by intervening alignment structures. The alignment structures provide accurate placement of the dual laser beams with respect to one another while also assuring thermal isolation of the laser diodes. The fabrication method employs photolithographic techniques to accurately position the alignment structures across an entire semiconductor wafer, thereby assuring accuracy in alignment of the assembled dual beam lasers. As a result, the need for multiple-step alignment operations commonly employed in the production of multiple diode laser devices is eliminated.

Abstract: A method of deflecting and steering laser beams of the kind that comprises generating two converging pumping beams defining between them a convergence angle .psi.. The two converging pumping beams are targeted on a predetermined intersection region of a third-order, non-linear polarization medium so as to intersect therein whereby each of said pumping beams is split in the said intersection region to form a plurality of scattered portions each of which interferes with the pumping beam from which it was formed to generate a light interference pattern, the light interference patterns thus generated from the two pumping beams causing self-generation of a common grating such that there emerge from said polarization medium two output beams each forming with a neighboring pumping beam a steering angle .THETA. which is controllable by variation of the magnitude of the wavenumber of at least one of the two pumping beams so as to form a wavenumber difference dk between the two pumping beams.

Abstract: A laser light beam generating apparatus includes at least one light beam source, first and second reflectors, a non-linear optical crystal element and an actuator. The light beam source emits a light beam. The non-linear optical crystal element is provided between the first reflector and the second reflector. A light beam emitted from the light beam source is incident on the non-linear optical crystal element through the first reflector. The actuator actuates at least one of the first and second reflectors along an optical axis of the light beam emitted from the light beam source.

Abstract: A frequency tunable waveguide extended cavity laser formed with a laser diode, a channel waveguide comprising an electro-optic material, a frequency tunable Bragg grating reflector formed in or on the channel waveguide and a pair of conducting electrodes. The frequency of radiation produced by the frequency tunable waveguide extended cavity laser is adjusted so as to be at a desired frequency by applying a voltage to the conducting electrodes. The device further incorporates a waveguide nonlinear optical frequency converter to produce frequency convened radiation at a higher frequency. Feedback means are included for dynamically controlling the desired frequency so as to be at a frequency for optimum frequency conversion.

Abstract: A single semiconductor diode laser array with multiple laser beams is used in a laser printer. The single diode laser array is formed by joining two semiconductor diode lasers. Each diode laser emits multiple laser beams that can have a different wavelength than the multiple laser beams of the other diode laser. The diode lasers can be made from different materials, such as GaAs/AlGaAs and GaInP/AlGaInP. The polarization of one diode laser can be orthogonal to the polarization of the other diode laser. The first diode laser has the dimensions of a long width and a short length. The second diode laser has the dimensions of a short width and a long length. The lasing elements are formed centrally to the width of each diode laser. The diode lasers are mounted on separate heatsink mounts. When the diode laser array is assembled, an insulator separates the lasing elements of each diode laser. Contact wires are attached to bonding pads located near the exposed ends or sides of each diode laser.

Abstract: The present invention is directed to providing compact systems and methods for producing and amplifying chirped pulses to provide high energy ultrashort pulses. Further, the present invention is directed to providing a compact system which is reliable and cost effective to fabricate. In accordance with exemplary embodiments, relatively compact tunable lasers can be used to directly generate long chirped optical pulses. For example, compact monolithic semiconductor lasers which have relatively small dimensions (e.g., dimensions smaller than large frame solid state lasers) and which permit their emission wavelength to be tuned (i.e., changed) relatively fast during the generation of an optical pulse can be used. These pulse sources eliminate any need for bulk components in the cavity of, for example, a mode-locked femtosecond laser. The relatively long chirped optical pulses can subsequently be amplified in plural amplification stages to increase their energy content.

Abstract: A gas laser, in particular a CO.sub.2 laser, contains as laser medium a gas that is excited into a plasma by a HF energy supply, in particular a microwave energy supply, whereas the HF waves are coupled into the laser medium (4) through a rectangular waveguide (1). In order to obtain a compact structure with an efficient coupling of the HF energy, coupling is ensured by means of a ribbon-shaped waveguide (3) that projects into the rectangular waveguide (1) and thus also allows the outcoupling on all sides of the rectangular waveguide.

Abstract: A tunable laser formed on a semiconductive wafer comprising a plurality of monolithically integrated optical amplifiers and a planar optical multiplexer is disclosed. According to the invention, one of the optical amplifiers is activated by energy, which amplifier produces a signal. The signal is carried along a waveguide associated with the optical amplifier and enters a reflective Dragone router, which is the preferred optical multiplexer. The reflective Dragone router functions, in conjunction with the activated optical amplifier, to define a wavelength selective optically transmissive pathway to create lasing action. Facet mirrors are cleaved in the semiconductive wafer defining the lasing cavity which includes the optical amplifiers, associated waveguides and the reflective Dragone router.

Abstract: Controlled, high-power laser oscillator. A single laser gain medium is used to efficiently generate high-power, controlled laser light without exposing the control elements to high-power radiation. The control element or elements are separated from the oscillator gain volume by a separator optic which permits only a portion of the energy from the gain volume to enter the region of the control elements, laser light having the desired characteristics being returned to the gain volume through the separator optic. Energy not entering the control region exits the laser as oscillator output energy in order to obtain high efficiency.

Abstract: A wavelength-division-multiplexed transmitter has a single modulator modulating the output of an array of individually actuable semiconductor lasers integrated onto the same substrate as the modulator. An optical combiner integrated onto the same substrate between each of the lasers and the single modulator combines the outputs of the lasers. One or more of the lasers are activated as desired for wavelength division multiplexing.

Abstract: A high powered OPO system which produces a substantially collimated, low divergence output beam is based on the use of an unstable resonator. An optical parametric gain medium, such as beta-barium borate (.beta.-BBO), lithium tri-borate (LBO), cesium borate (CBO), potasium tri-phosphate (KTP), or other similar materials is mounted within the unstable resonator with suitable tuning mechanisms. Optics are provided for supplying a pump beam through the optical parametric gain medium to induce gain. In a preferred system, the unstable resonator comprises a positive branch, confocal unstable resonator. Further the unstable resonator may be injection seeded for a narrow linewidth output.

Abstract: A slab laser amplifier array includes a plurality of parallel, stacked, laser resonators, with each resonator having a walk-off mode of propagation of laser light from an input side of the resonator to an output side of the resonator where the exiting light diffracts around the resonator mirror. A source of a plurality of phase related, for example co-phasal, light beams supplies phase related light to each input side. The source of phase related light may be a source of one single mode beam followed by a telescope with an aperture having plural stops or a co-phasal array of laser resonators. A laser array of open resonators also has circular concentric electrodes.

Abstract: Method and arrangement for locking a laser to an external cavity that is electronically tunable to provide an optical source that is highly coherent and which is frequency stabilized over a variable frequency range. Preferably, an injection laser is tightly coupled to an external acousto-optic cavity having a reflective mirror on its back facet and carried on an electro-optic crystal substrate. A transducer is coupled to the external cavity and converts an electrical sinusoidal input signal into an acoustic wave which travels along the electro-optic crystal substrate to modulate the refractive index of the material along the optical waveguide. The periodicity of the refractive index along the waveguide is accordingly determined to be equal to one half wavelength of the acoustic frequency propagating in the waveguide which locks the laser at a particular optical frequency determined by the refractive index profile. The arrangement is particularly desirable for frequency division multiplexing applications.

Abstract: A self-mode-locked ring cavity laser incorporating a laser crystal such as Ti:Sapphire includes an external cavity for producing self-starting of mode-locked operation. The external cavity receives a portion of one of the continuous wave beams from the ring cavity modulates it, and retroreflects it back to the ring cavity to initiate mode-locked unidirectional operation. The unidirectional mode-locked operation is in a direction which decouples the external cavity.

Abstract: A device includes a transmitter for transmitting a first optical signal towards a target, which incorporates an optical parametric oscillator. A receiver is capable of receiving a second optical signal from said target. The second optical signal is the reflected signal from the first signal. The receiver means comprises an optical parametric amplifier. A wavelength matching device matches the wavelengths produced by the optical parametric oscillator with that received from the optical parametric amplifier. The optical parametric amplifier is typically joined with a laser to form an optical parametric amplifier laser, while the optical parametric oscillator is joined with a laser to form an optical parametric oscillator laser.

Abstract: A pulsed solid state laser system is disclosed which utilizes a plurality of individual laser rods which are sequentially pumped and whose beans are combined into a single interleaved output bean. The individual laser rods are pumped at an average power level which is below that for maximum output power from each rod, thereby obviating the need for refrigeration cooling. A compact optical system is disclosed which permits a constant beam size even at different pump levels and other advantages. A compact cooling system is also disclosed.

Abstract: An apparatus for achieving in-phase mode operation of a diode laser. A photonic band gap mirror (photonic crystal) having a periodic lattice structure is placed in front of light emitted from one side of the laser diode array. Because of an incomplete photonic band gap in the photonic crystal, light normal to the crystal will be primarily reflected while light at an angle will be primarily transmitted through the mirror. Since in-phase emission is primarily normal and out-of-phase emission primarily off axis, the reflected light which is directed back into the laser cavity will be the predominant lasing mode. The out-of-phase mode primarily transmitted will have significantly larger losses. The resulting laser diode apparatus will therefore operate in-phase and produce a single lobe far-field distribution.

Abstract: The present invention encompasses both a method and an apparatus for fabricating a multiple beam semiconductor laser array, wherein the laser includes a plurality of semiconductor laser dies affixed in a linear fashion to a supporting heatsink. Accurate alignment of the lasers and control of interlaser spacing is achieved through the use of alignment structures formed on the mounting surface of the heatsink. Once assembled, the alignment structures remain in an abutting relationship with the ridge waveguides present on each of the semiconductor lasers. The method not only enables the accurate placement of the laser diodes relative to one another so as to reduce interlaser spacing error, but also eliminates the need for multiple-step alignment operations to produce the multiple diode laser array.

Abstract: In a form of the disclosure an array of coupled cavities (called minicavities) of a QWH semiconductor laser are defined by a native oxide of an aluminum-bearing III-V semiconductor material and are arranged serially end-to-end along the longitudinal direction. The native oxide confines the injected carriers and optical field within the cavities, resulting in reflection and optical feedback distributed periodically along the laser stripe. Single-longitudinal-mode operation is exhibited over an extended range. In a further form of the disclosure, two linear arrays of end-coupled minicavities are arranged side by side to obtain a two dimensional array, with resultant lateral coupling between the linear arrays. The two dimensional array exhibits mode switching and multiple switching in the light power (L) versus current (I) characteristic (L-I) with increasing current. In another form of the disclosure, a stripe laser is transversely coupled (or side-coupled) with a linear array of end-coupled minicavities.

Abstract: An integrated, multi-wavelength laser having formed on a substrate (12) a plurality of active, individually selectable waveguides (14), a passive output waveguide (16), and a diffraction grating (18) formed in a Rowland-circle spectrometer geometry. The frequency of the lasing light is determined by-the geometrical relationship of the selected active waveguide, the diffraction grating, and the output waveguide. The active waveguides are positioned such that lasing light cannot diffract between two active waveguides. Little crosstalk occurs because no carrier depletion occurs in the output waveguide.

Abstract: A semiconductor-laser-pumped solid-state laser apparatus having a semiconductor laser device, a solid state laser medium, and laser resonators. The semiconductor laser device has a plurality of emission points which are arranged on a straight line and from which pump light is generated. The laser resonators are disposed in correspondence with the emission points. A plurality of solid state laser beams can be generated by using one solid state laser medium.

Abstract: A dual-wavelength laser system with intracavity, sum-frequency mixing including a bifurcated resonant cavity having a first arm, a second arm and a common arm; a first laser element located in the first arm for providing a first input laser beam of a first wavelength; a second laser element located in the second arm for providing a second input laser beam of a second wavelength; a nonlinear-mixing element in the common arm; and a beam combining device for combining the first and second beams and submitting them to the nonlinear-mixing element for providing an output laser beam of a third wavelength whose energy is the sum of the energy of the input laser beams.

Abstract: A laser system having plural optical paths, each with a dielectric mirror for extracting a different wavelength of light from a laser beam, and a laser medium movable with respect to the different optical paths for injecting the laser beam into a desired optical path. The laser medium is mounted to a motor driven carriage for moving the laser medium with respect to the different optical paths.

Abstract: Laser resonator, particularly for carbon dioxide lasers, with two resonator nd mirrors having active material between two fully reflecting end mirror faces, which form an unstable resonator cavity, and with at least one third, completely reflecting mirror face reflecting the laser radiation prior to its coupling out through a coupling-out opening of the resonator. So that the laser only requires a reduced degree of coupling out and/or has an improved beam quality, it is constructed in such a way that, in addition to the unstable resonator cavity, between the two end mirrors is provided at least one stable resonator cavity and that the stable resonator cavity is made from the same active material of the third mirror face as the face of one of the two end mirrors with the face of the other end mirror.

Abstract: Apparatus for providing beams of laser radiation at wavelengths of 1.44 .mu.m and 1.064 .mu.m on demand. Two Nd:YAG lasers are arranged in a side-by-side configuration and operated to provide laser output at wavelengths of 1.44 .mu.m and 1.064 .mu.m, respectively. In the preferred embodiment, a reflective spectral filter comprised of two reflectors reduces the amount of 1.064 .mu.m radiation in the output beam from the 1.44 .mu.m laser by a factor of 100 to 1000, but only reduces the amount of 1.44 .mu.m radiation in the output beam from the laser by less than 2%. The apparatus also provides collinear addition of the output from the 1.064 .mu.m laser. This collinear addition enables output radiation from both lasers to be coupled together into a single optical fiber. In fact, a user can choose to operate either laser separately or to operate both lasers simultaneously.

Abstract: The optical mirror incorporates a lightguide (20) produced on a surface (23) of a substrate (22) and used for the propagation of a light beam (36) in a direction parallel to said surface, a cavity (30) made in the lightguide (20) and having in the propagation direction a first (32) and a second (34) walls oriented perpendicular to said direction and having in section approximately the shape of a circular arc, the distance (L) separating the two walls being equal to the radius of curvature (R) of the second wall at the optical axis (37) of the mirror and a reflecting material layer (38) deposited solely on the second wall in order to reflect the light beam towards the first wall, the second wall forming a concave reflecting surface.

Abstract: A laser diode array device (1, 11) according to a first aspect of the invention comprises a plurality of laser diode elements, some of which are formed as monitor laser diode elements for controlling the optical output of the remaining laser diode elements so that the device can operate at a power consumption rate by far lower than that of a conventional laser diode array device where the component laser diode elements needs to be individually controlled, while it can be assembled to an enhanced density. A laser diode array device (21) according to a second aspect of the invention comprises laser diode elements for signal transmission and monitor laser diode elements realized in the form of resonant cavities having a same length and sharing a common reflecting surface of a high-reflection film disposed at an end thereof so that the laser diode elements for signal transmission and the monitor laser diode elements show substantially identical light emitting characteristics.

Abstract: An interferometric semiconductor laser includes a cavity in the form of a Y and at east three individually actuatable active segments. A central segment couples together the individually actuatable active segments. The central segment is an active or passive segment that acts as a beam divider. The arrangement of the segments forms two resonator paths which contain at least one common active segment. At least one resonator path includes an active segment that does not belong to the other resonator path. In the absence of, or with the same actuation of the active segments, the optical path length of one resonator path differs from the optical path length of the other resonator path.

Abstract: Whenever any laser is interfaced with any type of optics there is always backscatter back into the laser. For diode lasers this backscatter makes it emit chaotic radiation where the frequency spectrum is broad and contains many different frequencies. This means that the laser has limited use as a source of information transfer in fibers. This weakness can be overcome, by driving the laser with an external cavity filled with a Kerr material. The addition of a Kerr material in the external cavity suppresses the chaos, or coherence collapse. Thus the new apparatus of laser plus external cavity filled with a Kerr material increases the stability of the diode laser.

Abstract: The invention relates to lasers, and more particularly to solid state lasers such as neodymium on lithium niobate crystal lasers. The invention provides a structure with several juxtaposed optical waveguides (12) sufficiently close to each other laterally to be coupled laterally. In order to take into account the risks of inhomogeneity in the refractive indices or inaccuracies in the dimensions which would alter the distribution of the electromagnetic field of the propagation supermode in the coupled structure, it is proposed to act on the value of the index of propagation in each guide using an individual control (generally electrical). Because of the variation in index, individually controlled, phase differences in the laser wave between the different guides are produced and these phase differences react on the composition of the electromagnetic field defining the supermode. It is possible to go as far as modifying the directivity of the laser beam by this electrical control.

Abstract: A system for combining a plurality of laser beams into a combined output beam from at least two laser sources includes the removal of conventional perpendicularly oriented output windows from each of the laser sources. Reflecting mirrors are positioned perpendicular to the optical axis at the rear of the two laser sources. A fully reflecting mirror is positioned perpendicular to the optical axis of the first laser source to reflect coherent light received from the first laser source. A beam splitter is positioned between the first laser source and the fully reflecting mirror at the intersection of the optical axes of the first and second laser source. The beam splitter directs a portion of received coherent light into a combined output beam, with the remainder being directed back to the first and second laser sources.

Abstract: A semiconductor light emitting device able to emit a high intensity, stable light. An edge surface lighting type light emitting diode array is formed on a substrate. A light emitting edge surface of each light emitting element is formed by an etching method. A surface of the substrate in front of the light emitting edge surface is formed in multiple stage so that a light beam is not reflected by the surface of the substrate.

Abstract: An optical parametric oscillator/laser system includes an optical pump source for generating pump radiation and an embedded dual optical resonator containing an optical parametric oscillator/laser crystal. The embedded dual optical resonator includes a laser resonator and an optical parametric oscillator resonator. The OPOL crystal is an optical parametric oscillator material doped with ions that exhibit lasing transitions. The pump radiation stimulates generation of laser radiation. When the laser radiation reaches the parametric threshold, optical parametric radiation is generated. In one embodiment, the laser resonator and the OPOL resonator are each defined by spaced-apart mirrors. In another embodiment, the OPOL system includes an OPOL rod having end caps at each end. Each end cap includes surfaces for internally reflecting the laser radiation and the parametric optical radiation in a closed loop path so that the OPOL rod and the end caps define an optical resonator.

Abstract: A Q-switched laser having a gain medium disposed within a first cavity and a second cavity whose optical path length is adjustable such that the quality of the first resonant cavity is affected. One aspect of the invention is the changing of the physical path length of the second cavity so as to effect the reflectivity of a mirror common to both cavities as seen from the first cavity. Another aspect of the invention is the incorporation, within the second cavity, of a material whose refractive index or absorption coefficient can be varied by the application of an electric field, a magnetic field, a temperature change or an applied pressure.