Abstract: A method of minimizing contamination of optical components of a laser resonator is disclosed. The resonator components are located in an enclosure, which may contain contaminants including water vapor and organic favor released by the optical components, mounts of the optical components, or the enclosure itself. The enclosure may also contain suspended particulate matter. In order to reduce the level of these contaminants, a purging system extracts gas from the enclosure and passes the gas through a desiccant, an organic vapor trapping material, and a particulate matter filter then returns the extracted gas to the enclosure. The purging system is particularly useful for ultrafast lasers and ultraviolet lasers where the power of the laser radiation increases the probability of destabilizing reactions between laser radiation and contaminants.

Abstract: A laser apparatus includes a semiconductor laser element, a surface-emitting semiconductor element including a first mirror, a second mirror, and a modulation unit. The semiconductor laser element emits first laser light having a first wavelength. The surface-emitting semiconductor element is excited with the first laser light, emits second laser light having a second wavelength which is longer than the first wavelength. The first mirror in the surface-emitting semiconductor element is arranged on one side of the first active layer. The second mirror is arranged outside the surface-emitting semiconductor element so that the first and second mirrors form a resonator in which the second laser light resonates. The modulation unit modulates the surface-emitting semiconductor element.

Abstract: A semiconductor laser device is formed by laminating optical confinement layers and active layers so as to dispose each of said active layers between said optical confinement layers, wherein one of the opposite ends perpendicular to the junction planes of the individual layers in the semiconductor multi-layer film is coated with a low reflection film and the other of the ends is coated with a high reflection film, wherein the low reflection film is an Al2O3 film having a resistivity of 1×1012 &OHgr;·m or more, preferably 1×1013 &OHgr;·m or more, and having a stoichiometric ratio composition, which is deposited by, for example, an electron cyclotron resonance sputtering process.

Abstract: The above discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by a laser of the present invention. In accordance with the present invention the laser comprises a housing defining a plurality of compartments therein, a folded waveguide disposed within the housing, the folded waveguide defining a plurality of channels having a substantially rectangular cross section for guiding a laser beam, a plurality of electrodes disposed in the plurality of compartments and juxtaposed along opposite surfaces of the waveguide and at least one power supply connected to the plurality of electrodes. The channels having a prescribed width to height ratio for a prescribed channel length for a given Fresnel number. At least one optical housing is provided. The optical housing is mounted to the laser housing, the optical housing including a plurality of beam turning mechanisms disposed within a plurality of compartments accessible for adjusting the beam turning mechanisms.

Abstract: An n-InP second upper cladding layer is laid on a p-InP lower cladding layer while an active layer having upper and lower boundary surfaces that are uniformly flat in an optical waveguide direction is interposed therebetween. A diffraction layer having a phase-shifted structure in the optical waveguide direction is interposed between the lower cladding layer and the active layer or between the second upper cladding layer and the active layer. The length L of the diffraction grating layer in the direction of the optical waveguide is L≦260 &mgr;m; a mean coupling factor &kgr; of a diffraction grating layer is &kgr;≧150 cm−1; and &kgr;L satisfies 5.6>&kgr;L>3.0.

Abstract: A method for the self-calibration of a tunable, diode pumped solid state laser in which the frequency or the wavelength of the laser radiation of the fundamental frequency and/or doubled frequency is changed by of changing the optical cavity length by means of a piezo-actuator or Brewster window over the total amplification bandwidth of the laser-active material. According to the method, the performance curves during the tuning of an etalon or corresponding optical elements arranged in the cavity are recorded and stored and a tuning function for the respective optical element or optical elements is generated (derived) from these curves by a microcontroller or computer. An optimum working point for the optical element or optical elements for maximum suppression of side modes is adjusted by a digital or analog regulator with the help of a learning curve (learning characteristic).

Abstract: The invention relates to an optical system in the ray path of a confocal fluorescence microscope, comprising at least one laser light source (1, 2), a device positioned in the illuminating/detecting beam (3, 4, 5) for separating the exciting light (8) from the fluorescent light (9), an objective (10) arranged between the device and the object (7), and a detector (11) positioned downstream of the device situated in the detecting beam (5). The aim of the invention is to increase the fluorescence yield of the system while retaining its compact structure.

Abstract: Infrared generation is disclosed. A first laser field having a first frequency associated with a first interband transition is generated. A second laser field having a second frequency associated with a second interband transition is generated. The generation of the first laser field occurs substantially simultaneously with the generation of the second laser field. A third laser field is generated from the first laser field and the second laser field. The third laser field has a third frequency associated with an intersubband transition. The third frequency is substantially equivalent to a difference between the second frequency and the first frequency.

Abstract: A long pulse power system for gas discharge lasers. The system includes a sustainer capacitor for accepting a charge from a high voltage pulse power source. A peaking capacitor with a capacitance value of less than half the sustainer capacitance provides the high voltage for the laser discharge.

Abstract: An electrically-pumped vertical-cavity surface-emitting laser (VCSEL) has multiple active regions. Embodiments of the invention provide an electrically-pumped VCSEL having a number of different p-i-n junction and electrode arrangements, which, in various embodiments, allow independent biasing of the multiple active regions, and, in other embodiments, allow simplified electrical connections.

Abstract: A method of controlling a unipolar semiconductor laser in the 4-12 &mgr;m mid-infrared range. This is an optical control method, unlike a purely electrical, power control method which injects a relatively large flux of electrons. The optical control method may advantageously include two optical beams of the same wavelength and a device for making those beams interfere in the active layer of the laser, the optical control beams having a much shorter wavelength than the wavelength of the unipolar laser and having a frequency capable of being modulated more rapidly than that of the laser.

Abstract: A solid-state laser rod pumping module has a stack-type semiconductor laser including a plurality of bar-shaped components that are stacked in a direction parallel to the axis of a solid-state laser rod. Each bar-shaped component includes a plurality of laser-light-emitting portions that are aligned and integrated in a direction orthogonal to the axis of the solid-state laser rod. The large divergence angle of the stack-type semiconductor can be compensated by including a light focusing component for focusing laser light emitted out of the stack-type semiconductor laser. The focused light is guided by a laser light guiding component disposed in a diffusive reflection tube. A light guiding component guides the focused light onto a solid-state laser rod located within the diffusive reflective tube, while maintaining the length of one side of the cross section of the guided light.

Abstract: A laser apparatus wherein a gain medium and an optical output assembly are mounted on a common, thermally conductive substrate which provides selective thermal control of the gain medium and output components on the substrate while avoiding unnecessary thermal control of other laser components, and methods for selectively cooling a gain medium and output components of a laser apparatus.

Abstract: Multiwavelength modelocked laser systems and methods for reducing intensity fluctuations and amplitude noise in each of the wavelength channels as well as manipulating the interwavelength phase coherence properties. The systems and methods can include lens, semiconductor optical amplifier, grating, cylindrical lens, rod lens and an approximately 7 nm MQW saturable absorber between mirrors for providing a laser cavity resonator for hybridly modelocked operation. Additional systems and methods can include two different positions for the saturable absorber inside the laser resonator which enables direction of the interwavelength phase coherence properties. Up to approximately 300 MHz optical pulse trains in each of up to approximately three channels can be generated. Combining gain flattening and noise suppression within the optical cavity of the modelocked laser can result in generating up to approximately 123 wavelength channels, each having up to approximately 6 Giga Hertz optical pulse trains.

Abstract: This invention provides a vertical-cavity surface-emitting laser device comprising a surface light-emitting part comprising a cavity consisting of two multilayer reflectors and an active region between them and a waveguide part for introducing induced light into the surface light-emitting part. The device is substantially independent of a temperature and allows a wavelength to be controlled after manufacturing the device.

Abstract: There is disclosed an improved optical device (10;10a), eg comprising a semiconductor optically active or optoelectronic devices such as lasers, modulators, amplifiers, switching structures, or the like, mounted on a heatsink (28;28a) The invention provides an optically active device (10;10a) comprising a device body (12;12a) having an active region (14;14a) and an optically passive region(s) (20;22) provided at one or more ends (24,26;26a) of the active region (14;14a); and a heatsink (28;28a); the device body (12;12a) and heatsink (28;28a) being retained in thermal association with one another such that a first end of the at least one of the optically passive region(s) (20,22;22a) adjacent an end of the active region (14;14a) is provided within an area of the heatsink (28;28a), and a second end of the said at least one optically passive region(s) (20,22;22a) is provided outwith the area of the heatsink (28;28a).

Abstract: A chiral fiber laser implemented in a fiber Bragg grating mimicking the advantageous optical properties of a cholesteric liquid crystal structure is provided. The dopant, the pitch, the core cross section and dimensions thereof, of the inventive chiral fiber laser as well as the core and cladding materials used in construction thereof, may be advantageously selected and configured to enable the inventive chiral fiber laser to produce lasing at a desirable wavelength. In another embodiment of the inventive chiral fiber laser, a tunable defect is introduced to provide tunable lasing corresponding to the wavelength at the defect mode. Multiple embodiments using coupled fiber optical pumping as well as direct optical pumping for excitation of the inventive chiral fiber laser are provided.

Abstract: Single-stripe GaAs/AlGaAs semiconductor optical amplifiers which simultaneously generates from four to more than twenty tunable WDM channels. A four channel version trsnsmits approximately 12 picosecond pulses at approximately 2.5 GHz for an aggregate pulse rate of 100 GHz. Wavelength tuning over 18 nm has been demonstrated with channel spacing ranging from approximately 0.8 nm to approximately 2 nm. A second version uses approximately 20 wavelength channels, each transmitting approximately 12 picosecond pulses at a rate of approximately 600 MHz. A spectral correlation across the multiwavelength spectrum which can be for utilizing single stripe laser diodes as multiwavelength sources in WDM-TDM networks. A third version of multiple wavelength generation uses a fiber-array and grating. And a fourth version of wavelength generation uses a Fabry-Perot Spectral filter. Also solid state laser sources and optical fiber laser sources can be used.

Abstract: A semiconductor pump laser comprises a ridge waveguide electro-optical structure, which converts a ridge injection current into light and an integrated wavelength selective facet reflector. This reflector controls the longitudinal modal operation of the pump laser. Specifically, the reflector comprises a first reflective structure for reflecting light to return through the ridge waveguide electro-optical structure. A second reflective structure provides wavelength-selective reflectivity when operating in combination with the first reflective structure. In other words, the phase of light reflected from the first and second reflective structures is such that the net reflectivity of the facet is wavelength selective, or favors certain wavelengths over other wavelengths.

Abstract: A hybrid WDM-TDM optical link employing a hybrid modelocked multi-wavelength semiconductor which provides approximately 4 to approximately 20 wavelength channels that makes possible modulated multiplexed data which when demultiplexed by ultra fast optical demultiplexing provides rates suitable for conventional electronic photo receivers. The link uses single-stripe GaAs/AlGaAs semiconductor optical amplifiers which simultaneously generate from approximately four to more than approximately twenty tunable WDM channels. Diode laser can also include InP, InGaAlP, InGaAsP, InGaP, InGaAs. A four channel version transmits approximately 12 picosecond pulses at approximately 2.5 GHz for an aggregate pulse rate of 100 GHz. When generating approximately 20 wavelength channels, each transmitting approximately 12 picosecond pulses at a rate of approximately 600 MHz, there is provided optical data and transmission systems operating at rates in excess of 800 Gbits/s.