Abstract: A laser apparatus for producing a laser light beam can include a gain medium; a pump light source to provide a pump light beam to the gain medium; a first reflector disposed between the first gain medium and the first pump light source and spaced apart from a gain portion of the first gain medium; a second reflector; and an output coupler. The first reflector is substantially reflective to the laser light beam and substantially transmissive to the pump light beam. The first and second reflectors and the output coupler define a folded beam path having a first portion and a second portion. The first portion of the beam path extends from the first reflector to the second reflector through the gain medium and the second portion of the beam path extends from the first reflector to the output coupler through the gain medium. The first and second beam paths define, within the gain medium, a non-zero folding angle.

Abstract: A laser apparatus for producing a laser light beam can include a gain medium; a pump light source to provide a pump light beam to the gain medium; a first reflector disposed between the first gain medium and the first pump light source and spaced apart from a gain portion of the first gain medium; a second reflector; and an output coupler. The first reflector is substantially reflective to the laser light beam and substantially transmissive to the pump light beam. The first and second reflectors and the output coupler define a folded beam path having a first portion and a second portion. The first portion of the beam path extends from the first reflector to the second reflector through the gain medium and the second portion of the beam path extends from the first reflector to the output coupler through the gain medium. The first and second beam paths define, within the gain medium, a non-zero folding angle.

Abstract: Fiber lasers include a fiber polarization controller to compensate for polarization variation In addition, fiber lasers include dual gain fibers to provide broader bandwidth for ultrashort pulse generation and amplification.

Abstract: Laser cutting and sawing can be performed on a variety of materials, transparent or non-transparent, including quartz, sapphire, glass, semiconductors, and diamonds. By direct generation of a special laser beam from a laser cavity and/or by shaping of a laser beam, unique characteristics of the beam in X- and Y-axes are utilized in the cutting and sawing of materials. Such a method and apparatus can reduce breakage and weight loss of the processed material while maintaining or increasing the cutting/sawing throughput.

Abstract: In an optical fiber system for delivering laser, a laser beam is focused onto an optical fiber at an injection port of the system. The end portions of the fiber have cladding treatments to attenuate stray light and cladding mode light, so as to enhance the protection of the outer layer joint points. Photodetector sensors monitor scattered stray light, cladding mode light, and/or transmitted cladding mode light. Sensor signals are provided to a control unit for analyzing the fiber coupling performance. If need be, the control unit can control a laser shutter or the like to minimize or prevent damage. In materials processing applications, the photodetector signals can be analyzed to determine the processing status of a work piece.

Abstract: A system and method for photolithographic mask repair. The system includes a structure for supporting a mask to be operated on, a laser emitting device for effecting mask repair, a light source adjacent the support structure for selected illumination of the mask, a laser processor for effecting sequential angular manipulation of a laser beam projecting from the laser emitting device, a computer device for controlling the sequential angular manipulation so as to capture a generally complete waveform of the beam, and a microscope for multi-aspect viewing of the mask during navigation of the beam about the mask. The computer device, simultaneously with manipulation of the beam, effecting fine motion control of the beam, controlled movement of the motorized aperture for effecting the sequential angular manipulation, controlled support structure movement, and image data processing.

Abstract: A light beam with non-uniform cross-sectional intensity profile is positioned into a central portion and two side lobes and the two side lobes are folded over the central portion to form a concentrated beam at a focus plane having substantially uniform intensity profile. The partitioning and folding may be done by mirror pairs disposed along the axis of the beam, or a trapezoidal prism.

Abstract: A method and device are provided to accomplish laser driven pyrolytic, photolytic and photoactivativation process requiring controlled atmosphere without the use of gas tight cells.A method and device are provided to correct clear faults on a photo-lithographic mask by metallic deposition on the mask at standard temperature and pressure. The deposition is formed by the pyrolytic decomposition of an organometallic gas mixture which may include chromium and molybdenum hexacarbonyls, and a buffer gas. The decomposition is done utilizing a laser beam. The device may be incorporated into a system which has other members used to correct opaque faults in the same mask.

Abstract: An autofocusing microscope includes a spot marker assembly for projecting a spot marker on the sample surface. The image of the spot marker is continuously scanned while the objective lens is moved along a preselected range of distances from said sample surface. The lens is then moved to the optimum focusing in accordance with the scanning.

Abstract: A frequency doubler for a Q-switched laser is disclosed in which a Type II SHG crystal is oriented to generate a second harmonic frequency beam in response to the orthogonal components of a fundamental beam. After the fundamental beam makes a round trip through the SHG crystal, any differential phase delays between the orthogonal components due to birefringence are eliminated to improve the efficiency of the cavity.

Abstract: A frequency doubler for a laser is disclosed in which a Type II SHG crystal is oriented to generate a second harmonic frequency beam in response to the orthogonal components of a fundamental beam. After the fundamental beam makes a round trip through the SHG crystal, any differential phase delays between the orthogonal components due to birefringence are eliminated to improve the efficiency of the cavity.

Abstract: A frequency doubler for a laser is disclosed in which a Type II SHG crystal is oriented to generate a second harmonic frequency beam in response to the orthogonal components of a fundamental beam. After the fundamental beam makes a round trip through the SHG crystal, any differential phase delays between the E and O rays of the fundamental beam due to birefringence are eliminated to improve the efficiency and stability of the cavity.

Abstract: The disclosure is of a segmented YAG laser rod having segments cemented together and its method of manufacture.

Abstract: The disclosure is of a segmented YAG laser rod having segments cemented together and its method of manufacture.

Abstract: A reliable, low cost, light weight, CW pumped Nd:YAG laser with optional Q-switching is provided with a rail for the laser optics that isolates the optical axis from movement of the laser head housing. A laser pot is provided with a housing and quickly detachable cover both molded of a resin that is impervious to water, optically opaque, possesses low thermal deformation, high dielectric strength and resistance to damage by light and UV radiation. The pot is formed with a cavity lined by molded reflectors and divided by a septum interposed between the laser rod and lamp. The lamp is removable with the cover and is readily coupled with the lamp sockets designed for accepting variations in lamp manufacturing tolerances. The power supply for the laser resonator is transformerless and parallel triggering is employed for the lamp. The cooling system is provided with a water immersed heat exchanger defined by a coated copper tube that prevents ionic action.

Abstract: A method and apparatus for providing coincident orthogonally-polarized laser beams having twice the frequency of a fundamental frequency emitted by a laser source is disclosed. A second harmonic generator within a laser resonator cavity causes frequency-doubled laser beams to travel in opposite directions along an axis thereon. One of the beams undergoes a polarization change of substantially 90.degree. and is returned for travel along the laser axis in the same direction as a second frequency-doubled beam which has not undergone a polarization change. The orthogonally-polarized beams are then emitted through an output mirror designed for transmitting beams of twice the frequency of the fundamental beam.

Abstract: A laser system is disclosed for facilitating transient surface heating and/or melting and regrowth of amorphous, polycrystalline or imperfect crystalline semiconductor wafer material. This system also has specific application to gettering of impurities and the annealing-out of defects within a semiconductor wafer. In the system, a number of circular target-wafers are arranged around the periphery of a turntable. The turntable rotates while a simple, slow-moving beam-delivery system moves radially with respect to the turntable delivering a helical scan which may also be in the form of a multiple-track. Use of the turntable with a multiple wafer load allows efficient batch-processing. Blocking masks may be employed when it is desired to irradiate only selected areas of the semiconductor substrates.