Abstract: Method and apparatus are disclosed for beam dividing and shaping, in which the beams from laser diode array are divided in a plurality of sections along the slow axis and the sections of beams are then recombined along their fast axis so that the Lagrange invariant of the resulting beam increased approximately by n-fold in fast axis and reduced approximately by n-fold in slow axis. With the inclusion of above apparatus in diode laser modules, the main objectives of constructing high-efficiency solid state lasers can be achieved.

Abstract: An apparatus and method for automatically analyzing and controlling intensity of a train of high speed, high power multi-level optical pulses. The invention includes an optical pulse generator for generating the train of high speed, high power, multi-level optical pulses, wherein the optical pulse generator provides a low optical intensity level and a medium optical intensity level and a high optical intensity level. A photodetector is optically coupled with the optical pulse generator for generating a train of electrical pulses having amplitude levels in response to optical intensity levels of the train of optical pulses. At least one reference is employed, wherein an analyzer electrically coupled with the reference and the photodetector for analyzing the amplitude levels of the train of electrical pulses in comparison to the reference. A controller is electrically coupled with analyzer for generating a high correction signal based upon the analysis of the amplitude levels.

Abstract: A Q-switched microlaser is provided that is capable of supporting a zig-zag resonation pattern in response to side pumping of the active gain medium so as to effectively lengthen the microresonator cavity without having to physically lengthen the microresonator cavity. As such, the microlaser can generate pulses having greater pulse widths and correspondingly greater pulse energies and average power levels than the pulses provided by conventional microlasers of a similar size. A corresponding fabrication method is also provided according to one embodiment of the present invention that permits a plurality of side pumped Q-switched microlasers to be fabricated in an efficient and repeatable manner.

Abstract: A gallium nitride semiconductor laser device has an active layer (6) made of a nitride semiconductor containing at least indium and gallium between an n-type cladding layer (5) and a p-type cladding layer (9). The active layer (6) is composed of two quantum well layers (14) and a barrier layer (15) interposed between the quantum well layers, and constitutes an oscillating section of the semiconductor laser device. The quantum well layers (14) and the barrier layer (15) have thicknesses of, preferably, 10 nm or less. In this semiconductor laser device, electrons and holes can be uniformly distributed in the two quantum well layers (14). In addition, electrons and holes are effectively injected into the quantum well layers from which electrons and holes have already been disappeared by recombination. Consequently, the semiconductor laser device has an excellent laser oscillation characteristic.

Abstract: An insulating member (4) of an amorphous structure partially opened to expose a substrate (1; 1, 2, 3) is formed on the substrate. At least a compound semiconductor (5, 51, 52) containing at least nitrogen as a constituent element is deposited on the insulating member (4) and the substrate (40) exposed by the opening thereby to form a semiconductor material (1, 5, 51, 52). A semiconductor material (6, 7) configured of the first semiconductor material or configured of the first semiconductor material and another semiconductor material grown on the first semiconductor material is processed thereby to form a semiconductor device.

Abstract: Based on an oscillation ON/OFF signal and an output state instruction signal output to a high-voltage generating circuit (101) from a power supply control apparatus (301), heater voltage applied from a heater circuit (201) to a heater of a magnetron (2) is controlled depending on whether the magnetron (2) is stopped from oscillating or is continuously or intermittently operating. The heater voltage of the magnetron (2) measured during the intermittent operation is controlled to be higher than that measured during the continuous output and to be lower than that measured while the oscillation is stopped, thereby reducing the change in temperature of the heater and providing a lower limit temperature at which the magnetron (2) can oscillate stably. This configuration increases the service life of the magnetron (2) used for a microwave excitation laser.

Abstract: Laser source including materials with negative index of refraction dependence on temperature and with temperature independent coincidence between cavity modes and a set of specified frequencies such as DWDM channels in telecommunications applications. The free spectral range may be adjusted to equal a rational fraction of the specified frequency interval. The operating frequency may be defined by a frequency selective feedback element that is thermo-optically tuned by the application of heat from an actuator without substantially tuning the cavity modes. The operating frequency may be induced to hop digitally between the specified frequencies. In a particular embodiment, semiconductor amplifier and polymer waveguide segments form a linear resonator with a thermo-optically tuned grating reflector. In a further embodiment, an amplifier and two waveguides from a tunable grating assisted coupler form a ring resonator.

Abstract: A passive mode-locked linear-resonator fiber laser using polarization-maintaining fibers and a saturable absorber to produce ultra short pulses and a long-term reliable operation with reduced maintenance. Such a fiber laser can be configured to produce tunable pulse repetition rate and tunable laser wavelength.

Abstract: An optical source generates optical signals as a result of varying polarization states to achieve oscillation within an optical loop. The optical signals have narrow spectral width and the optical source is tuneable, so that optical components stimulated by the optical signals can be characterized over a predefined wavelength range with high wavelength resolution. The optical loop includes an optical gain element, a tuneable filter, and a polarization scrambler that provides a varying polarization transfer function. The optical gain element has sufficiently high gain within the passband of the tuneable filter and the polarization transfer function is sufficiently varied to attain oscillation within the optical loop, thereby generating the optical signals. The varying polarization transfer function of the polarization scrambler produces a corresponding variation in the polarization of the generated optical signals, which are coupled from the optical loop to an output.

Abstract: An n-type GaAs buffer layer 702, an n-type AlGaInP cladding layer 703, a multiple quantum well active layer 704 made of AlGaInP and GaInP, a first p-type AlGaInP cladding layer 705a, an optical guide layer 707, a second p-type cladding layer 705b, a p-type GaInP saturable absorption layer 706, and a third p-type AlGaInP cladding layer 707 are sequentially formed on an n-type GaAs substrate 701. In this structure, the volume of the saturable absorption layer is reduced, and the optical guide layer is provided. As the volume of the saturable absorption layer becomes smaller, the more easily the carrier density can be increased, the more easily the saturated state can be attained, and the more remarkable the saturable absorption effect becomes. Thus, a semiconductor laser having stable self-oscillation characteristics and, as a result, having a low relative noise intensity is realized.

Abstract: A method for selecting laser and pump frequencies for a quasi-two level solid state laser with a selected laser host and operating the laser with the selected laser and pump frequencies, the host having a fluorescence probablility P(&ngr;) over a frequency range from &ngr;i to &ngr;f, has the steps: (a) determining for the laser host, a power weighted average fluorescence frequency <&ngr;F> given by ⟨ v F ⟩ = 1 ( v f - v i ) ⁢ ∫ v i v f ⁢ v ·

Abstract: Disclosed is a low threshold vertical cavity surface emitter having a low refraction index confining layer (36) directly in the cavity spacer. This allows a ½ wavelength cavity spacer and lateral size of as low as 2 &mgr;m. Also disclosed is a method of rapid temperature annealing to seal a III-V crystal and inhibit oxidative degradation.

Abstract: An apparatus and a method for laser frequency stabilization include a laser, a modulator, a derivative module, a Fabry-Perot etalon, a photodetector, a balanced mixer, a signal processing module, and a feedback control module. The laser has an output and lases at a single frequency. The laser has a desired frequency and provides an optical signal including a substantial frequency chirp signal. The modulator is coupled to the laser and provides a modulation signal for modulating the laser. The derivative module is coupled to the modulator and provides a derivative signal which is a time derivative of the modulation signal. The Fabry-Perot etalon is coupled to the output of the laser and has a frequency response including a plurality of resonances. One of the plurality of resonances is centered on the desired frequency. The etalon filters the optical signal according to the frequency response.

Abstract: The invention includes a solid state laser which outputs wavelength emission &lgr;ss centered about 946 nm, combined with a lasing waveguide which includes a Yb doped optical waveguide such that when the &lgr;ss output is inputted into the lasing waveguide the lasing waveguide produces a wavelength emission &lgr;y centered about 980 nm. The invention further includes the utilization of pump light with optical waveguide amplifying devices.

Abstract: An intracavity, frequency-doubled, external-cavity, optically-pumped semiconductor laser in accordance with the present invention includes a semiconductor multilayer surface-emitting gain-structure surmounting a Bragg mirror. An external concave mirror and the Bragg-mirror define a stable laser-resonator including the gain-structure. A birefringent filter is located in the resonator, inclined at an angle to the resonator axis, for selecting a fundamental frequency of the laser-radiation within a gain bandwidth characteristic of semiconductor structure. An optically-nonlinear crystal is located in the laser-resonator between the birefringent filter and the gain-structure and arranged to double the selected frequency of laser-radiation. The gain-structure is coated with a dichroic coating which reflects the frequency-doubled radiation and transmits the fundamental radiation and optical pump-light.

Abstract: A semiconductor laser of present invention is constructed by an aluminum oxide (Al2O3) film on an end surface opposed to a beam emission surface of the semiconductor laser, a silicon nitride (SiNx, or Si3N4) film on the aluminum oxide film, and a silicon oxide (SiO2) film on the silicon nitride film. These films are made successively by a method of Electron Cyclotron Resonance (ECR) sputtering.

Abstract: Optical wavelength control method and apparatus which are capable of controlling an optical wavelength of a light source with a central wavelength which is uncertain and unstable at nanometer order is disclosed. In the optical wavelength control apparatus, the control target light entered from the variable wavelength light source is scanned at a prescribed period and optical pulses having a phase corresponding to the optical wavelength of the control target light are obtained. Then, a phase difference between a phase of the optical pulses and a phase corresponding to a reference optical wavelength is detected, and the variable wavelength light source is controlled by feeding back the phase difference to the variable wavelength light source such that the optical wavelength of the control target light is controlled by an optical frequency pulling with respect to the reference optical wavelength according to the phase difference.

Abstract: The gallium nitride group semiconductor laser device of this invention includes an active layer made of a nitride semiconductor formed between cladding layers and/or guide layers made of a nitride semiconductor on a substrate, wherein a light absorption layer is formed between the substrate and one of the cladding layers located closer to the substrate, the light absorption layer being made of a semiconductor having an energy gap substantially equal to or smaller than an energy gap of the active layer.

Abstract: Disclosed is an optical component packaging assembly including a rectangular plastic box with an upper half and a lower half. In the lower half, a thermal plastic vacuum formed insert is positioned within the lower half. The lower insert has a recess. The recess has opposed convex ends and central finger recesses. The opposed convex ends prevent the end faces of the optical component from being brought into contact with the insert. The convex ends may be v-shaped or semi-circular. The finger recesses provide convenient access to the laser rod so that the person unpackaging the laser rod from the optical component packaging is most likely to engage the laser rod at a center portion thereof rather than grasping the laser rod at the end faces thereof, thereby inadvertently damaging the optical surfaces of the laser rod.

Abstract: A precision positioning mount for UV-cured adhesives that provides adhesive junctions between modular assembly mounts and structural elements. Contact edges are placed on a first fixating area of an adhesive junction. The contact edges are pronounced edges of faces that slide along a second fixating area during the adjustment process. Thus, the assembly modules and structural elements are precisely referenced before, during and after their positioning and orientating. First and second fixating areas form a cavity that provides a volume for the adhesive. The mounts and structural elements are preferably made of sapphire for increased thermal conductivity. The elements of the assembly mounts are modular and interchangeable and provide various positioning modes.