Abstract: According to the present invention, laser performance is improved by appropriately matching the spectral periods of various etalons within the laser cavity. A first embodiment of the invention is a discretely tunable external cavity semiconductor laser where a grid fixing etalon is present in the laser cavity, the grid fixing etalon free spectral range (FSR) is a whole number multiple of the laser cavity FSR, and the grid fixing etalon FSR is a whole number multiple of the chip etalon FSR. A second embodiment of the invention is a fixed wavelength external cavity semiconductor laser where the chip etalon FSR is a whole number multiple of the laser cavity FSR, and a mode suppressing etalon is inserted into the laser cavity such that the mode suppressing etalon FSR is a whole number multiple of the chip etalon FSR. A third embodiment of the invention is a tunable external cavity semiconductor laser where the chip etalon FSR is a whole number multiple of the laser cavity FSR.

Abstract: An IAU laser is stabilized to reduce intensity fluctuations. The laser comprises an IAU gain medium disposed in an optical resonance cavity and a multiphoton absorbing medium disposed in the cavity to reduce intensity fluctuations. A pump source to excite the gain medium is coupled to the cavity. In operation, the multiphoton absorbing material absorbs primarily at high intensity levels, effectively increasing the loss at high intensities. In an advantageous embodiment, the active medium comprises erbium-doped glass and the multiphoton absorber comprises a body of semiconductor exhibiting two-photon absorption at the emission wavelength.

Abstract: The invention concerns an ultrahigh frequency emitting device, having: at least a first and a second microlaser (22, 24), emitting at two different frequencies &ohgr;1 and &ohgr;2, means of slaving the first and the second microlaser frequency-wise, an array of N elements (N≧2) (52, 54, 56, 58) placed on the path of the beam of the second laser, each element making it possible to impose a phase delay on the beam which passes through it, N means (26, 28, 30, 32) for mixing the beam emitted by the first laser and each of the N delayed beams, and for producing N signals of frequency &ohgr;1-&ohgr;2, N antenna-forming means (34, 36, 38, 40) for emitting radiation at the frequency &ohgr;1-&ohgr;2.

Abstract: A waveguide device in the form of either a solid-state laser or amplifier is divided into separate pumping and output mode control sections along at least one direction of the device by leaving a portion of a core of the device unclad or by depositing appropriate coatings on different sections of the core or by contacting/bonding materials with different refractive indices to different sections of the core or by a combination of these approaches. The core has a pump input surface for receiving pumping radiation at a pumping wavelength and one or more output surfaces for emitting a laser beam at an output wavelength. When used as an amplifier, the core also has a laser input surface which may be the same as one of the output surfaces.

Abstract: The present invention relates to a gas laser with a high-voltage electrode 12 and a ground electrode 14, which electrodes 12, 14 are disposed relative to each other so as to form a discharge gap 16 between them, and with high voltage generating means including a circuit having at least one storage capacitor and at least one secondary capacitor 18, 20, said secondary capacitor 18, 20 being disposed in the area of said high-voltage electrode 12 within a discharge chamber 32 filled with laser gas. Said secondary capacitor 18, 20 includes at least one external surface 28, 28′ oriented towards said high-voltage electrode 12 and made of a material which is inert with respect to said laser gas, which external surface 28, 28′ forms at least one boundary surface of a flow channel 26, 26′ for said laser gas.

Abstract: The invention concerns an optical coupler formed of a photonic optical fiber (2) assembled by melting and stretching with at least one multimode optical fiber (4, 6). The phototonic fiber can be used to inject or extract a signal, whereas the multimode fibers can be used to inject pump light. The invention is able to in particular effectively couple multimode pumps in a laser cavity formed by a double cladding fiber. In this case, the optical fiber is not used to inject a signal, but to provide the coupler with a digital opening and a diameter adapted to those of the cavity. The invention is also able to couple one or several multimode pumps in a double cladding fiber. In this case, this makes it possible to retain in the coupler for the signal transmitted through the photonic fiber a mode diameter greater than or equal to the mode diameter at the inlet or outlet of the coupler.

Abstract: An optically pumped laser with an Er:Yb: doped solid state gain element is disclosed, which is passively mode-locked by means of a saturable absorber mirror. The laser is designed to operate at a fundamental repetition rate exceeding 1 GHz and preferably at an effective wavelength between 1525 nm and 1570 nm. Compared to state of the art solid state pulsed lasers, the threshold for Q-switched-mode-locked operation is substantially improved. Thus, according to one embodiment, the laser achieves a repetition rate beyond 40 GHz. The laser preferably comprises means for wavelength tuning and repetition rate locking.

Abstract: Lenses 102, 103, and 104, a diffraction grating 105, a mirror 106, a light isolator 107, an arm 108, a pulse motor 109, and a pulse motor 110 operate in conjunction for mechanically roughly adjusting the wavelength of laser light generated by an LD 101, and the wavelength of laser light generated by the LD 101 is electrically finely adjusted in a wavelength adjustment section 30.

Abstract: A laser includes a first optically reflective element; a second optically reflective element opposed to and aligned with the first optically reflective element to define a laser cavity having an optical axis; an optical pump source for injecting optical pump energy into the laser cavity along the optical axis; a solid-state dye gain element having a thin host in which a dye is dissolved that is interposed between said first and second optically reflective elements along the optical axis for transforming the optical pump energy into a resonant optical signal; and a cooling element in thermal contact with the solid-state dye gain element for absorbing heat energy from the solid-state dye gain element to control the temperature of the solid-state dye gain element.

Abstract: A multiple spectral line Raman laser having adjustable relative power output between different spectral lines is provided. The laser includes a lasing cavity, first and second reflectors optically coupled to a back end of the cavity that reflects substantially all light having wavelengths of &lgr;1 and &lgr;2, respectively, and a tunable reflector assembly optically coupled to a front end of the cavity that reflects a selected proportion of said light having wavelengths of &lgr;1 and &lgr;2 in response to a single source of strain to control relative power output of light at these wavelengths. The lasing cavity may be a linear length of gain fiber, and the tunable reflector may include a single fiber Bragg grating (FBG) having a trapezoidal reflection profile, or a pair of fiber Bragg gratings mounted on either side of a flexible substrate such that when the substrate is bent, one FBG stretches while the other is compressed.

Abstract: A method for recording an image on a photosensitive surface, comprising: producing a primary pulsed light beam; converting the primary light beam, in a light wavelength converter separate from the pulsed light source, to an ultraviolet pulsed light beam; modulating the ultraviolet pulsed beam; and scanning the ultraviolet pulsed light over the surface to record an image on the photosensitive surface.

Abstract: An apparatus for laser beam targeting and method of laser cutting or marking of an article is disclosed. In one aspect of the invention, the laser beam targeting apparatus comprises at least one laser scan head comprising at least one motor driven deflector for scanning a linearly polarized laser beam across a target, and a polarization control device comprising at least one Brewster plate wherein the polarization control device rotates the Brewster window around an axis parallel to the laser beam to thereby gradually transmit or deflect the laser beam in order to control the level of laser beam energy scanning across the target in accordance with the movement of the at least one deflector and a laser scanner.

Abstract: A diode pump, solid state laser deep UV laser source is described for customized ablation in photo-refractive surgery. The solid-state deep UV laser source is tailored to have a pulse repetition rate of about 1 kHz and a relatively small spot size at both positions of the cornea and the scanner. Such a deep UV laser source enables the use of fast scanner and the implement of fast eye tracker. One embodiment of such a deep UV laser source comprises a passively Q-switched microchip laser, a diode-pumped multiple pass amplifier, and a wavelength converter.

Abstract: A laser diode array, having one or a plurality of electrically mounted laser diode bars, in which current paths through the array are sufficiently parallel and close together to result in a substantial reduction of inductance. As a result, higher duty cycles at lower pulse widths are possible. In some embodiments, a heatsink is provided as part of an overall assembly. The heatsink may provide part or all of a return portion of the current path for the array. Alternatively, the heatsink may be insulated from the rest of the array. The array itself may be fabricated in any of a number of known manners.

Abstract: A apodized chiral fiber grating consists of a chiral fiber with a variable effective grating strength along different regions of its length, such that the effective grating strength gradually increases from one end of the chiral fiber until a peak effective grating strength is reached and then gradually decreases at the same rate towards the other end of the fiber. Optionally, the effective grating strength remains stable for a portion of the fiber before decreasing. Other forms of grating strength variations in different regions of the chiral fiber are also contemplated. The effective grating strength variation produces an apodized chiral fiber that possesses desirable characteristics that greatly reduce or eliminate the sidelobes in the fiber's spectral response.

Abstract: The present invention is a micro-cavity laser and methods related thereto. In the preferred embodiments, the micro-cavity laser comprises a laser pump signal in a fiber waveguide which is optically coupled to a micro-cavity resonator through a fiber taper. The micro-resonator includes a gain medium necessary for lasing action. The lasing frequency can be determined based upon the gain medium, the micro-cavity structure, as well as frequency selective elements such as gratings incorporated into the micro-cavity. The tapered fiber waveguide permits the micro-cavity laser to operate without a break in the fiber waveguide. In the preferred embodiments, the micro-cavity resonator is constructed from a doped silica or a semiconductor material. The present invention provides a compact laser with improved emissions and coupling efficiencies. Alternative configurations include multiple micro-cavities on a single fiber waveguide and/or utilizing multiple waveguides attached to one or more micro-cavity resonators.

Abstract: The invention provides a two-stage laser mode of photolithographic molecular fluorine laser system for matching the center wavelength of an oscillation-stage laser to the center wavelength of an amplification-stage laser, thereby oscillating a laser beam having a low spectral purity and a narrow linewidth. The laser system is of the two-stage mode comprising an oscillation-stage laser 10 and an amplification-stage mode 20. The center wavelength of a laser beam emitted out of the oscillation-stage laser 10 is compared with and substantially matched to the center wavelength of a laser beam emitted out of the amplification-stage laser 20 when the latter is oscillated by itself.

Abstract: An excimer or molecular fluorine laser system includes a wavelength calibration module permitting the wavelength of the narrow band output beam to be calibrated to a specific absolute wavelength. The module is preferably a lamp which contains at least one species including platinum with an optical transition within the emission spectrum of the laser system. Light from the lamp is preferably coincident at a spectrometer with a beam portion from the laser, and the laser beam wavelength is calibrated by simultaneous analysis at the spectrograph.

Abstract: Methods and systems for laser-based processing of materials are disclosed wherein a scalable laser architecture, based on planar waveguide technology, provides for pulsed laser micromachining applications while supporting higher average power applications like laser welding and cutting. Various embodiments relate to improvements in planar waveguide technology which provide for stable operation at high powers with a reduction in spurious outputs and thermal effects. At least one embodiment provides for micromachining with pulsewidths in the range of femtoseconds to nanoseconds. In another embodiment, 100W or greater average output power operation is provided for with a diode-pumped, planar waveguide architecture.

Abstract: Methods and systems for using a laser type clock to produce a train of ultra-stable optical pulses. The methods and systems include generating an approximately 10 GHz ultralow noise pulse train from a harmonically modelocked laser having an intracavity Fabry-Perot etalon filter from a semiconductor lasers such as ring lasers, and the like. System output can have residual phase modulation(PM) noise values of approximately 18 fs and amplitude modulation(AM) noise values of approximately 0.05% RMS, and residual phase modulation(PM) noise values of approximately 94 fs and amplitude modulation(AM) noise values of approximately 0.05% RMS.