Abstract: A focal distance adjustable laser module including a cap having a tapered laser firing hole, a lens holder press-fitted into the cap to hold a rubber packing ring and a lens on the rubber packing ring and having an inner thread at the back side, a laser diode holder holding a mounting plate and a laser diode on the mounting plate and having an outer thread at the front side threaded into the inner thread of the lens holder, a circuit board secured to the mounting plate at the back and connected to the laser diode to control its operation, and a spring mounted inside the lens holder and imparting a backward pressure to the laser diode holder to prohibit displacement of the laser diode holder relative to the lens holder.

Abstract: A sealed gas laser tube (10) has a pair of electrically insulated electrodes (53, 54) supported in the tube (11) adapted to couple to an external RF supply (30).

Abstract: A semiconductor laser unit includes a semiconductor laser device, a first temperature detector that detects a temperature in the vicinity of the semiconductor laser device, and an electronic cooler that heats or cools the semiconductor laser device. The semiconductor laser unit also includes first and second branching devices for extracting first and second branched lights from an oscillation light outgoing from the semiconductor laser device, a band pass filter that transmits only a light of a predetermined wavelength band among the first branched light, and an optical filter that transmits the second branched light so that a transmission loss is increased or decreased in one way with a change of the wavelength within a wavelength band where the oscillation wavelength of the semiconductor laser device can be changed, to output a second monitor light.

Abstract: A Ring Laser Gyroscope, constructed on a low thermal expansion, lithium containing, glass-ceramic frame, with a negatively charged trap electrode applied directly to the frame surface near the cathode for the purpose of intercepting mobile positive ions transported under the influence of the anode to cathode electric field during laser operation.

Abstract: The illumination energy of an excimer laser is measured and adjusted to always effect illumination at constant energy. A laser beam output from an optics is reflected by a mirror, and applied to a sample. A beam profiler is disposed behind the mirror to measure the energy of an illumination laser beam. An energy attenuating device disposed between another mirror and the optics is operated based on the measurement value so that the energy of the laser beam applied to the sample is kept constant.

Abstract: A system for improving the thermal uniformity, beam quality and lasing efficiency of composite solid state lasers by reducing parasitic oscillations and confining the laserable medium to a location in the composite laser component where it is most efficient is provided. The improvements are accomplished by bonding one or more laser-inactive or laser-radiation-absorbing layers to a laserable medium.

Abstract: A laser having a line-narrowing output coupler. This output coupler reflects a portion of light generated in the gain medium and provides a spectral narrowing of that reflected light. A portion of the line narrowed beam is directed back into the gain medium for further amplification and a portion is transmitted as a part of the laser output. In a preferred embodiment, the laser is line narrowed in the rear as well as by the line narrowing output coupler.

Abstract: The present invention relates to a laser generator in which a laser beam is generated by energizing a laser medium and is amplified optically with optically amplifying mirrors, and the laser beam is received by a absorber, wherein a spacer 9 having a through hole 9a for passing therethrough the laser beam and at least one small second through hole 9b is arranged at a circumference of an absorber 7, and a cooling medium 12 circulates in the small second through hole 9b of the spacer 9. In this structure, if a scattering laser beam is generated at the circumference of the laser beam absorber, a parallelism of the optical amplifying mirrors is maintained so that the laser generator can generate the stable laser beam.

Abstract: A heatsink and an optical system are provided for use in conjunction with a dissipating semiconductor or electronic device, such as a light source, that generate a large amount of heat and is required to be cooled for optimum performance. The light source may be a laser diode or laser array or bar and is generally mounted on the heatsink with other optical components, such as collimating and focusing lenses, isolators or terminal ends of optical fibers, for coupling the output beam of the light source in aligned relation to these optical elements. Because of the higher temperature operation of such light sources, the heat generated causes thermal expansion of mechanically connected structures, such as between the heatsink for supporting the light source and its associated submount and an underlying support, usually a cooler.

Abstract: In order to produce higher harmonics more efficiently in a laser having a first optically nonlinear crystal acting as a frequency doubler, and at least one further optically nonlinear crystal acting as a frequency multiplier disposed behind the first nonlinear crystal in the direction of propagation of laser radiation produced by the laser, the first to second-to-last optically nonlinear crystals are selected to each have a walk-off angle in the range of 0.1.degree. to 6.degree., and all of the optically nonlinear crystals are disposed relative to one another in such a way that the plane of the principal section of one crystal contains a direction of small angular acceptance with respect to phase matching of a following crystal.

Abstract: New sensing and diagnostic methods are implemented with multimode fiber Bragg gratings (MMFBG) and methods for sensor addressing and multiplexing are described. Real time structural strain and vibration monitoring using optical time domain reflectometry (OTDR) is discussed. The first all-mode, wave optics calculations of the reflectivity of Bragg gratings in highly multimode optical fibers are presented, including the effects of individual mode power changes due to microbending transducer loss upstream from the grating. Two categories of multimode fiber gratings are possible, independent mode and mode coupling, and the fabrication differences between these types of gratings are described. The reflectivity properties of independent mode multimode fiber gratings are examined and compared to single mode fiber gratings.

Abstract: An optical end-pumped fiber laser doped with one or more rare-earths and with distributed feedback (DFB) via a fiber Bragg-grating, which is oscillating on two orthogonally polarized wavelengths. The distance between the wavelengths may be tuned by changing the birefringence of the fiber. The laser may be applied as a polarimetric sensor in which an asymmetrical force changes the wavelength separation, or as a tunable two-wavelength source. A particular preferred field of application is for measuring the pressure in pipes, to determine the flow.

Abstract: A crystal substrate, with an adhesive uniformly applied to its entire rear surface, is fixed to the inner wall of an element housing. By adjusting the thickness of a wall of the element housing, forming grooves in the wall, or fixedly attaching a deadweight to the wall, the resonant frequency of the element housing is adjusted so as to restrain the optical waveguide element from resonating. Further, by mounting the optical waveguide device on a printed board via an elastic member or the like, propagation of the vibration to it is suppressed.

Abstract: A desktop medical laser generator (10) for laser surgery has a base plate (12) and an optical assembly (14) mounted thereon. The optical assembly (14) has an improved lamp housing (16) having two identical shell sections (44) and associated components for housing a YAG rod (60) and a lamp (58). Light emitted from the lamp housing (16) is doubled in frequency by a KTP crystal (26), monitored by two power detectors (32,34) and emitted through an output connector (36). A line power control system (90) insures the current drawn from a standard wall receptacle (80) does not exceed accepted limits. An output power detection system (90) closely monitors output power.

Abstract: A diode-pumped high performance solid state laser has at least one pump module comprising at least two laser diode arrays which transversely irradiate a solid state laser rod. The path length of the radiation emitted by a laser diode array through the solid state laser rod and the required absorption path for this radiation, determined by the emission wavelength of this radiation and the doping of the laser-active medium, are adapted to one another extensively in different ways.

Abstract: A light expanding system for converting a light beam generated from a point-like light source into a collimated linear or planar light beam is disclosed herein. According to an embodiment of the invention, a system for producing a linear light beam includes a beam collector and a light pipe adjacent to which a multiplicity of specially configured microprisms are located. The light expanding system according to this embodiment is suitable for use in devices utilizing a linear light beam, such as a scanner. According to another embodiment of the invention, a system for producing a planar light beam includes, in addition to the beam collector and light pipe described above, an additional light pipe with adjacent microprisms. The light expanding system according to this embodiment of the invention can be used, for example, in displays, road signs, medical research equipment, instrument meters or jewelry; to light pictures or art work; or as part of a see-through lighting system far use in dentistry and surgery.

Abstract: A laser having two feedback elements at least one which is wavelength selective, is provided with a demountable optical connector located between the gain medium of the laser and the wavelength selective feedback element. An optical waveguide is utilized to direct optical radiation between the demountable optical connector and the wavelength selective feedback element. The demountable optical connector, for example, a mechanical fibre connector allows the wavelength selective feedback element, for example, a fibre grating, to be exchanged cheaply, simply and quickly, and thus allows the wavelength of operation of the laser to be altered.

Abstract: A heat sink for slab lasers has two heat conductive members. Each heat conductive member has a generally planar surface and is configured such that a solid state laser medium is disposable therebetween while contacting the planar surfaces thereof. There is at least one window formed in at least one of the heat conductive members for facilitating pumping of the solid state laser medium. The two heat conductive members cause heat to be removed from the solid state laser medium in a manner which mitigates thermal focusing and depolarization of laser radiation stimulated within the solid state laser medium.

Abstract: An intracavity modulated pulsed laser and methods of using the same. In one preferred form, an intracavity modulated pulsed laser comprises an amplification medium, a pulsed pumping source, a beam modulator, and two mirrors, one totally reflective and one partially reflective for generating at least one laser output burst comprising a plurality of sub-pulses having variably controllable peak powers. In another preferred form, a non-linear crystal is utilized to double the frequency of each laser output burst. In still another preferred form, a fluorescence feedback control circuit is utilized to control the beam modulator.

Abstract: An eyesafe laser system includes a Q-switch crystal formed of a semiconductor host material having noncentrosymmetric tetrahedral substitutional sites doped with transition metal ions in concentrations from about 0.001 to about 0.10 atomic percent, which functions as to be a saturable absorber of light at eyesafe wavelengths with a relatively long relaxation lifetime. Co.sup.2+ :ZnSe has been demonstrated to have advantageously high absorption cross section and advantageously high relaxation lifetime at both 1.54 .mu.m (Er:glass laser) and 1.6 .mu.m (Er:YAG laser). Other candidate host materials include other zinc chalcogenides, cadmium chalcogenides and zinc oxide.