Abstract: Embodiments of a wavelength tunable optical coupler, integrated optical components, and lasers are disclosed. The tunable optical coupler, the integrated optical components, and the lasers include thermo-optic organic material that has an index of refraction which can quickly vary in response to changes in temperature. By controlling the temperature in the thermo-optic organic material through the use of heaters or coolers, the optical coupler, the integrated optical components, and the lasers can be quickly and selectively tuned over a broad range of wavelengths with high spectral selectivity.

Abstract: A subject of the invention is to reduce the temperature dependence of an etalon as a wavelength locker for a semiconductor laser device and so forth. Concretely, it is to restrict the lowering of the wavelength locking performance of the etalon dependent on the temperature variation. A means to solve the subject is the use of an air gap etalon. Concretely, the means is provided with a media plate and parallel plane plates on both sides of the media plate. The two parallel plane plates and the space between them constitute the air gap etalon.

Abstract: After forming domain inverted layers 3 in an LiTaO3 substrate 1, an optical waveguide is formed. By performing low-temperature annealing for the optical wavelength conversion element thus formed, a stable proton exchange layer 8 is formed, where an increase in refractive index generated during high-temperature annealing is lowered, thereby providing a stable optical wavelength conversion element. Thus, the phase-matched wavelength becomes constant, and variation in harmonic wave output is eliminated. Consequently, with respect to an optical wavelength conversion element utilizing a non-linear optical effect, a highly reliable element is provided.

Abstract: A laser includes an Nd:YVO4 crystal end-pumped with diode-laser light having a wavelength at which the absorption coefficient for Nd:YVO4 is less than about 0.35 (35%) of the absorption coefficient at 808 nm.

Abstract: Speckle of a laser beam is reduced by inserting an anti-speckle apparatus in the beam path to disrupt its spatial coherence while maintaining its temporal coherence. In one embodiment, the anti-speckle apparatus is a phase retarder plate bearing periodic optically-coated regions. Transmission or reflection of the beam through coated and uncoated regions causes an internal phase shift of first beam portions relative to second beam portions, thereby disrupting spatial coherence. Size and thickness of the coated regions can be carefully tailored to meet requirements of stepper and scanner equipment manufacturers for maximum allowable spatial coherence expressed as a minimum permissible number of coherent cells across the beam cross-section. An alternative embodiment of an anti-speckle apparatus is a scattering plate bearing a roughened surface. Transmission or reflection of the beam by the roughened surface disrupts the beam's spatial coherence.

Abstract: A light wavelength converting element which can reduce an amount of light fed-back to a semiconductor laser. The light wavelength converting element converts a wavelength of a fundamental wave which enters from a first end surface side of an optical waveguide to thereby emit a converted wavelength wave from a second end surface side thereof. The second end surface is inclined with respect to the side surface of the optical waveguide. Also provided is a wavelength stabilized laser having a semiconductor laser, a device which feeds a laser beam emitted from the semiconductor laser back to the semiconductor laser, and a band-pass filter. An optical length between the semiconductor laser and the device is made to be longer than a coherent length of the semiconductor laser, thus improving linearity of a current vs. light output characteristic.

Abstract: A device (10) for producing high frequency radiation using a source of elliptically polarized radiation is disclosed based on: irradiating a frequency multiplication medium having a screw axis (16) symmetry of approximate Nth order symmetry, oriented so that said elliptically polarized radiation propagates in parallel to the screw axis (16). Also, a method for producing high frequency radiation is disclosed based on irradiating a frequency multiplication medium having a screw axis (16) of approximate Nth order symmetry with elliptically polarized radiation so that the elliptically polarized radiation propagates in parallel to the screw axis (16). Furthermore, a method of producing a beam of high frequency radiation composed of only a limited number of wavelengths is disclosed whereby the intensity of a beam (22) interacting with a frequency multiplication medium is selected so that only a limited number of wavelengths is emitted.

Abstract: A process evaluates an aging property of a distributed Bragg reflector (DBR) laser. The process includes illuminating a Bragg grating of the distributed Bragg reflector (DBR) laser with light while the DBR laser is both supplied a tuning current and not lasing. The process also includes performing an action to the DBR laser responsive to a wavelength of a Bragg peak in a portion of the light reflected by the Bragg grating and a value of the tuning current supplied during the illuminating.

Abstract: An ultra-broadband, variable and multiple wavelength, waveform shaping apparatus is disclosed that excels with the ability to yield light pulses shaped in waveform, variable and multiple in wavelength over an ultra-broad bandwidth, the pulses being as short as in the order of pico-seconds or less, or even in the order of femto-seconds.

Abstract: A semiconductor laser device including a light reflecting facet positioned on a first side of the semiconductor device, a light emitting facet positioned on a second side of the semiconductor device thereby forming a resonator between the light reflecting facet and the light emitting facet, and an active layer configured to radiate light in the presence of an injection current, the active layer positioned within the resonator. A wavelength selection structure is positioned within the resonator and configured to select a spectrum of the light including multiple longitudinal modes, the spectrum being output from the light emitting facet. Also, an electrode positioned along the resonator and configured to provide the injection current, and a tuning current that adjusts a center wavelength of the spectrum selected by the wavelength selection structure.

Abstract: An optical module includes a light-emitting device that outputs laser light, a temperature detection unit that is arranged in proximity to the light-emitting device and detects the temperature of the light-emitting device, a wavelength monitor unit that receives laser light outputted from the light-emitting device and having passed through an optical filter and monitors the wavelength of the laser light, and a temperature adjustment unit that adjusts the wavelength of laser light outputted from the light-emitting device based on a signal outputted from the wavelength monitor unit. The temperature adjustment unit adjusts the wavelength of the laser light so as to fall within a wavelength range, in which the wavelength is adjustable by the wavelength monitor unit, based on a signal from the temperature detection unit, and then adjusts the wavelength of the laser light so as to be locked at a predetermined wavelength based on the signal from the wavelength monitor unit.

Abstract: A laser oscillator comprises a laser medium, an optical excitation laser diode that irradiates the laser medium with light, a polarizer disposed on an optical path of the laser medium at a first end thereof, a first Porro prism disposed with the optical path coinciding with a point on a ridgeline thereof and with the ridgeline parallel or perpendicular to a plane of incidence of the polarizer, and a second Porro prism disposed on the optical path of the laser medium at a second end thereof with the optical path coinciding with a point on a ridgeline thereof. An angle formed by the two ridgelines of the first and second Porro prisms is a predetermined angle other than 0 degrees, 90 degrees, 60 degrees, 45 degrees and 36 degrees, 30 degrees.

Abstract: An error signal generation system and method for continuous and accurate positioning of a tunable element used in association with a coherent light source. A tunable element is positioned in a coherent light beam with a fixed frequency or wavelength, and a detector is positioned in association with the light beam and tunable element that is capable of generating an error signal indicative of spatial losses associated with the positioning of the tunable element in the light beam. A tuning assembly is operatively coupled to the tunable element and detector and is configured to position the tunable element according to the error signal generated by the detector.

Abstract: A semiconductor laser comprises a sapphire substrate, an AlN buffer layer, Si-doped GaN n-layer, Si-doped Al0.1Ga0.9N n-cladding layer, Si-doped GaN n-guide layer, an active layer having multiple quantum well (MQW) structure in which about 35 Å in thickness of GaN barrier layer 62 and about 35 Å in thickness of Ga0.95In0.55N well layer 61 are laminated alternately, Mg-doped GaN p-guide layer, Mg-doped Al0.25Ga0.75N p-layer, Mg-doped Al0.1Ga0.9N p-cladding layer, and Mg-doped GaN p-contact layer are formed successively thereon. A ridged hole injection part B which contacts to a ridged laser cavity part A is formed to have the same width as the width w of an Ni electrode. Because the p-layer has a larger aluminum composition, etching rate becomes smaller and that can prevent from damaging the p-guide layer in this etching process.

Abstract: The invention relates to a gas discharge laser including a discharge tube (1), in which a gas is present and which has at least one aperture (19) through which a laser beam emerges or at which a laser beam is reflected. For withdrawing a partial amount of the gas contained in the discharge tube (1), at least one gas withdrawal point (9) is present, from which the withdrawn gas is supplied to a sintered filter (11) for being cleaned. The cleaned gas may be led in via at least one gas inlet point (27) in the zone of the aperture (19). The invention further relates to a method of operating a gas discharge laser, and the use of a sintered filter for cleaning gas withdrawn from a discharge tube (1) of a gas discharge laser.

Abstract: A wavelength-locked, integrated optical signal source structure using a semiconductor laser device is disclosed. The optical source structure has a semiconductor laser formed on a semiconductor substrate, and an etched portion coupled with an output end of the semiconductor laser. The etched portion is configured to pass on a first amount of light beam radiated by the semiconductor laser, and to reflect a second amount of light beam by a given reflection angle. A multiple microcavity is formed in a position spaced apart from the etched portion, and the first amount of light beam is incident upon the multiple microcavity. The optical source structure has a first optical detector for detecting the first amount of light beam passing through the multiple microcavity, and a second optical detector for detecting the second amount of light beam reflected by a slanted, reflecting surface portion of the etched portion.

Abstract: An adjusting device for a multi-beam source unit includes a mounting bracket, a base member rotatably mounted on the mounting bracket and a multi-beam laser diode provided with light emitting points positioned substantially in a straight line with respect to each other. The multi-beam laser diode is mounted on the base member and radiates a laser beam from the light emitting points. The base member rotates such that the laser beam is radiated onto a predetermined position of an image recording plane of a scanning optical system.

Abstract: The invention describes a surface-emitting laser (VCSEL) with lateral current injection. The pump current (4), from the contact face (2) on the decoupling side, in a first region (12) outside the resonator volume, is carried predominantly parallel to the resonator axis, and in a second region (13) is conducted predominantly perpendicularly to the active volume (9). A contact geometry is also described, which brings about automatic regulation of the size of the active volume (9) as a function of the pump current (4).

Abstract: In a laser apparatus, precision of wavelength control, wavelength stability and speed of wavelength control are increased, and an optical component is prevented from being polluted. A ball screw is used a feed screw of a feed screw mechanism that changes the orientation angle of the optical component.

Abstract: A cooled mirror device for laser systems or the like, comprising a main mirror body and a mirror cover rigidly connected to the main mirror body, wherein the main mirror body and/or the mirror cover have a cooling device, wherein the mirror cover is made from an aluminum material, and coated with copper or another reflection-enhancing material to form a reflection-enhancing mirror surface.