Abstract: In a slab laser, a gas mixture containing carbon dioxide CO2 is formed as a laser-active medium in a discharge space which is formed between two plate-shaped metal electrodes, the flat faces of which are located opposite one another. A resonator mirror is arranged on each of the mutually opposite end faces of the discharge space, the mirrors forming an unstable resonator parallel to the flat faces. At least one of the mutually facing flat faces is provided either on the entire flat face with a dielectric layer the thickness of which is greater on at least one sub-surface than in the remaining area of the flat face, or the at least one flat face is provided with a dielectric layer exclusively on at least one sub-surface.

Abstract: A gas-discharge waveguide CO2 laser has a Z-shaped folded waveguide formed by three ceramic tubes. Ends of the adjacent tubes are shaped and fitted together to form a common aperture. The tubes are held fitted together by spaced-apart parallel discharge electrodes. Four minors are arranged to form a laser-resonator having a longitudinal axis extending through the tubes.

Abstract: An RF power-supply for driving a carbon dioxide CO2 gas-discharge laser includes a plurality of power-oscillators phase-locked to a common reference oscillator. Outputs of the phase-locked power-oscillators are combined by a power combiner for delivery, via an impedance matching network, to discharge-electrodes of the laser. In one example the powers are analog power-oscillators. In another example, the power-oscillators are digital power-oscillators.

Abstract: A thin beam laser crystallization apparatus for selectively melting a film deposited on a substrate is disclosed having a laser source producing a pulsed laser output beam, the source having an oscillator comprising a convex reflector and a piano output coupler; and an optical arrangement focusing the beam in a first axis and spatially expanding the beam in a second axis to produce a line beam for interaction with the film.

Abstract: A gas-discharge waveguide CO2 laser has a Z-shaped folded waveguide formed by three ceramic tubes. Ends of the adjacent tubes are shaped and fitted together to form a common aperture. The tubes are held fitted together by spaced-apart parallel discharge electrodes. Four mirrors are arranged to form a laser-resonator having a longitudinal axis extending through the tubes.

Abstract: A command apparatus (10) for a plurality of laser power supplies (11, 12) comprises: a command generating section (5) generating commands for the laser power supplies; and a separating section (36) separating the generated commands into a bias command, an output command, an offset command and a gain command, wherein the bias command and the output command are common to the laser power supplies, the offset command and the gain command are defined at least in accordance with the discharge tubes corresponding to the laser power supplies respectively, wherein the command apparatus further comprises a transmitting section (37) transmitting, to the laser power supplies, the bias and the output command which are common to the laser power supplies and, transmitting the offset and the gain command defined at least in accordance with the discharge tubes corresponding to the laser power supplies respectively, corresponding to the laser power supplies.

Abstract: A laser device is provided. The laser device includes a laser tube, and power devices distributed uniformly along the length of the laser tube.

Abstract: The invention provides microchannel lasers having a microplasma gain medium. Lasers of the invention can be formed in semiconductor materials, and can also be formed in polymer materials. In a microlaser of the invention, high density plasmas are produced in microchannels. The microplasma acts as a gain medium with the electrodes sustaining the plasma in the microchannel. Reflectors are used with the microchannel for obtaining optical feedback to obtain lasing in the microplasma gain medium in devices of the invention for a wide range of atomic and molecular species. Several atomic and molecular gain media will produce sufficiently high gain coefficients that reflectors (mirrors) are not necessary. Microlasers of the invention are based on microplasma generation in channels of various geometries. Preferred embodiment microlaser designs can be fabricated in semiconductor materials, such as Si wafers, by standard photolithographic techniques, or in polymers by replica molding.

Abstract: A laser may comprise a ceramic body including a first wall and a second wall opposite the first wall, a first mirror positioned at first ends of the first and second walls, a second mirror positioned at second ends of the first and second walls opposite the first ends, the first and second walls and the first and second mirrors defining a slab laser cavity within the ceramic body. The laser may further comprise a first electrode positioned outside the laser cavity and adjacent to the first wall of the ceramic body and a second electrode positioned outside the laser cavity and adjacent to the second wall of the ceramic body, wherein a laser gas disposed in the laser cavity is excited when an excitation signal is applied to the first and second electrodes. In some embodiments, the first and second mirrors may form a free-space multi-folded resonator in the slab laser cavity. In other embodiments, the first and second mirrors may form a free-space unstable resonator in the slab laser cavity.

Abstract: An oscillator housing includes a main body unit that is shaped into a frame and formed of a metallic material and a cover unit that is formed of a metallic material to cover openings of the main body unit, and has an outer wall that has an arc cross section perpendicular to the optical axis and extends in the optical axis direction and side walls that are connected to the both ends of the outer wall in the optical axis direction. When the cover unit is fixed to the main body unit with a fixing member, the outer wall having an arc shape is configured such that force is generated in the height direction towards the outside of the oscillator housing on the connecting portion of the cover unit with the main body unit.

Abstract: The proposed gas discharge laser comprises extended solid main discharge electrodes, at each of which at least one ultraviolet pre-ionizer is placed, a gas flow area being formed by means of dielectric gas flow guides and the work surfaces of main electrodes and the pre-ionizers being placed outside of the gas flow area for illuminating a space between the main discharge electrodes through a gap defined between the main electrodes and dielectric guides. The proposed invention makes it possible to design a gas discharge laser for a high pulse repetition frequency mode with high-quality laser radiation.

Abstract: The invention relates to a two-stage laser system well fit for semiconductor aligners, which is reduced in terms of spatial coherence while taking advantage of the high stability, high output efficiency and fine line width of the MOPO mode. The two-stage laser system for aligners comprises an oscillation-stage laser (50) and an amplification-stage laser (60). Oscillation laser light having divergence is used as the oscillation-stage laser (50), and the amplification-stage laser (60) comprises a Fabry-Perot etalon resonator made up of an input side mirror (1) and an output side mirror (2). The resonator is configured as a stable resonator.

Abstract: An RF excited laser assembly includes a pair of opposed electrodes, and at least one inductor. The pair of opposed electrodes defines an inter-electrode gap that provides a discharge volume for laser propagation within a gas medium. The pair of opposed electrodes define one or more discharge-free regions within a laser-free region in the inter-electrode gap. The least one inductor is electrically connected to both electrodes and extends between the electrodes within the inter-electrode gap and inside of the one or more discharge-free regions within the laser-free region.

Abstract: One aspect of the disclosed subject matter describes a gas discharge laser chamber. The gas discharge laser chamber includes a discharge region formed between a first electrode and a second electrode, a tangential fan for circulating gas through the discharge region, wherein the fan is proximate to an input side of the discharge region, an input side acoustic baffle proximate to the input side of the discharge region. The input side acoustic baffle includes a vanishing point leading edge, a vanishing point trailing edge, a gas flow smoothing offset surface aligning a gas flow from a surface of the input side acoustic baffle to an input side of a cathode support in the discharge region, a plurality of ridges separated by a plurality of trenches, wherein the plurality of ridges and the plurality of trenches are aligned with a direction of gas flow through the discharge region and wherein the plurality of ridges have a random pitch between about 0.3 and about 0.7 inch.

Abstract: The invention provides a method for 3D modeling of a three-dimensional tubular structure of an examination object from 2D projection images (D) of the structure taken from different projection directions. The method has the following steps: reconstruction of a 3D image from the 2D projection images (D); selection of at least one 3D central line point (MO) in the 3D image, said 3D central line point being located in the structure; segmentation of 3D central line points (M) of the structure in the 3D image; forward projection of the 3D central line points (M), which have been segmented in the 3D image, into 2D projection images (D?); determination of border points of the structure in the 2D projection images (D?) on the basis of 3D central line points (Z) that have been projected in; and back-projection of the border points from the 2D projection image (D?) into the 3D image.

Abstract: An optical element holding and extraction device is provided. The device includes an optical element, an optical element holder having a tubular gripping portion and a tubular extraction portion connected at one end to the tubular gripping portion, and a retainer that is slideably carried on the tubular extraction portion. The diameter of the tubular extraction portion is less than the tubular gripping portion. In addition, the tubular gripping portion grips the peripheral edge of the optical clement. The device may be used in a variety of gas lasers, including excimer lasers.

Abstract: A cooling structure (16) for use inside a ceramic cylindrical tube (11) of a metal vapor laser (10) to cool the plasma in the tube (11), the cooling structure (16) comprising a plurality of circular metal members (17, 31) and mounting members (18, 34) that position the metal members (17, 31) coaxially in the tube (11) to form an annular lasing volume, with the metal members (17, 31) being axially spaced from each other along the length of the tube (11) to prevent the metal members from shorting out the current flow through the plasma in the tube (11) and to provide spaces through which the heat from localized hot spots in the plasma may radiate to the other side of the tube (11).

Abstract: A circuit configuration for detecting a functional disturbance has a first and a second differential amplifier. The outputs of the differential amplifiers are connected to the inputs of a gate. One input of the differential amplifiers is in each case connected to a reference potential terminal. The respective other input of the first and second differential amplifiers is connected to a monitoring means, which responds in the event of a change in the supply voltage at a supply potential terminal of the circuit configuration.

Abstract: A long wavelength infrared laser system is disclosed where radiation from laser sources such as frequency-doubled Nd:YAG or a Cr:LiSAF is used to resonantly pump a gain medium consisting of a holmium-doped fluoride crystal having a high active ion concentration. The laser pump source has a pulse duration that may be short enough to gain switch a particular transition or long enough to allow end-pumping with high energy densities without damage. The gain material has an absorption approximately resonant with the pump source wavelength, and the dopant concentration is selected to maximize absorption strength for a given excitation. The output radiation from the laser system consists of one or more wavelengths including, in particular 3.9 nm but also other infrared wavelengths such as 1.4 &mgr;m, 2.9 &mgr;m and 3.4 &mgr;m., several of which may be produced simultaneousely from the same laser material through the mechanism of cascade transitions.

Abstract: An electro-absorption modulated laser is provided having three sections, a laser section, an isolation section, and a modulation section. The laser section produces light along a straight waveguide path. The modulation section also has a straight waveguide path, but is angled with respect to the laser section's path. The isolation section between the other two sections includes a path that is collinear with the respective laser or modulation section at each end, but is gradually curved in the middle.

Abstract: A gas laser gas has an elongated cavity in which are disposed a first elongated electrode tube having an inner diameter, and a second elongated electrode tube disposed coaxially within the first electrode tube and having an outer diameter smaller than the inner diameter of the first electrode tube and spaced therefrom so as to provide a gas discharge chamber therebetween. The second electrode tube provides a gas exit chamber therewithin, and the first electrode tube is spaced from the wall of the cavity to provide a gas entry chamber thereabout. The electrode tubes permit gas to flow therethrough from the gas entry chamber to the gas exit chamber. The electrodes may be formed from a gas permeable material such as sintered metal, or formed from a non-permeable material with openings therein. The electrodes may have coolant flowing therethrough.

Abstract: A power efficient continuous wave gas ion laser system, associated laser tube and method are described. The system uses a fixed electrical input power and a power factor corrected power supply producing an output voltage and an output current from the fixed input electrical power. A gas ion laser tube is configured for use in the system having a particular cavity length which is established as a distance between a first mirror and a second mirror for operation using the output voltage and the output current. The system may be configured to provide a light output power improvement of approximately thirty percent over prior laser systems. In one feature, a laser tube is configured for providing the improved light output power in a conventional laser head configuration such that the laser tube may directly replace laser tubes in prior installations. Existing and new laser installations may benefit.

Abstract: A test circuit operable to examine both differential outputs and single outputs of a device under test (DUT), the circuit comprises a first circuit having as inputs a first output of the DUT and a first set of independent reference voltages, and an output of the first circuit coupled to a plurality of comparators. The test circuit further comprises a second circuit having as inputs a second output of the DUT and a second set of independent reference voltages, and an output of the second circuit coupled to the plurality of comparators. The test circuit further comprises a select circuit coupled to outputs of the comparators, the output of the first circuit and the output of the second circuit. The select circuit outputting the outputs of the first circuit and the second circuit or outputting the outputs of the comparators.

Abstract: A gas laser oscillator having at least three discharge tubes disposed along the optical axis, and a spacer having an opening centered on the optical axis. The spacer is disposed between a partially reflective mirror and the closest discharge tube.

Abstract: A gas laser oscillator having at least three discharge tubes disposed along the optical axis, and a spacer having an opening centered on the optical axis. The spacer is disposed between a partially reflective mirror and the closest discharge tube. Further, the discharge tubes are disposed in series along the optical axis, and satisfy the following three formulas simultaneously: 1 Formula 1 r1/r2 > 1.0 Formula 2 L2/(L1 + L2) < 0.85 Formula 3 r3/r2 < 1.

Abstract: A gas laser oscillator having at least three discharge tubes disposed along the optical axis, and a spacer having an opening centered on the optical axis. The spacer is disposed between a partially reflective mirror and the closest discharge tube. Further, the discharge tubes are disposed in series along the optical axis, and satisfy the following three formulas simultaneously: r1/r2>1.0  Formula 1 L2/(L1+L2)<0.85  Formula 2 r3/r2<1.4  Formula 3 where the sum of lengths of a pair of discharge tubes disposed at both ends in optical axis direction is L1, the inside diameter of these discharge tubes is r1, the sum of lengths of the other discharge tubes in the optical axis direction is L2, the inside diameter of these discharge tubes is r2, and the inside diameter of the opening of the spacer is r3.

Abstract: Decay time in scintillator compositions comprising yttrium or lutetium and gadolinium oxides and europium oxide is decreased by incorporating therein at least one of the oxides of ytterbium, samarium, praseodymium, neodymium, dysprosium, holmium, thulium, cerium and erbium as an acceptor. Other properties including afterglow and radiation damage are maintained at acceptable levels.

Abstract: Decay time in scintillator compositions comprising yttrium or lutetium and gadolinium oxides and europium oxide is decreased by incorporating therein at least one of the oxides of ytterbium, samarium, praseodymium, neodymium, dysprosium, holmium, thulium, cerium and erbium as an acceptor. Other properties including afterglow and radiation damage are maintained at acceptable levels.

Abstract: Optical microcavities are potentially useful as light emitters for, e.g., flat panel displays. Such microcavities comprise a layer structure, including two spaced apart reflectors that define the cavity, with a layer or layers of organic (electroluminescent) material disposed between the reflectors. We have discovered that a microcavity can simultaneously emit radiation of two or more predetermined colors such that the emission has a desired apparent color, exemplarily white. Emission of two or more colors requires that the effective optical length of the cavity is selected such that the cavity is a multimode cavity, with the wavelengths of two or more of the standing wave modes that are supported by the cavity lying within the emission region of the electroluminescence spectrum of the active material. A particular embodiment with two organic emitting (active) layers is disclosed.

Abstract: A high temperature laser assembly capable of withstanding operating temperatures in excess of 1500.degree. C. is described comprising a segmented cylindrical ceramic lasing tube having a plurality of cylindrical ceramic lasing tube segments of the same inner and outer diameters non-rigidly joined together in axial alignment; insulation of uniform thickness surround the walls of the ceramic lasing tube; a ceramic casing, preferably of quartz, surrounding the insulation; and a fluid cooled metal jacket surrounds the ceramic casing.

Abstract: A high current, pulsed, high repetition rate, electric discharge, extreme ultraviolet and Xray laser. The low inductance discharge bore is constructed from a plurality of discs (18). The bore segments are separated from one another by spacers constructed from a refractory electrical insulator (20). The components in contact with the gas discharge are constructed from high temperature materials with low sputtering rates and low rates of ion burial. Gas return holes (74) are provided in the bore segments discs. Xray reflecting mirrors form an optical cavity.

Abstract: A discharge portion of an ion laser tube is formed of either amorphous carbon or crystalline graphite member having an amorphous carbon layer on its surface.

Abstract: A gas discharge laser includes a cylindrical symmetric discharge tube, having a prescribed gas therein at a low pressure, centered within a microwave-resonant cavity immersed in an axial magnetic field. Appropriate mirrors, optically aligned with a longitudinal axis of the discharge tube, are positioned at each end of the plasma column, one of which is partially transmissive. A pair of Brewster windows, or a pair of flat windows with antireflective coatings, one at each end of the discharge tube, are interposed between the mirror and discharge tube. Electromagnetic energy in the microwave range, e.g., greater than 1 GHz, is injected into the cavity and made to resonate in an appropriate mode. A large portion of the resonating energy is coupled into the discharge tube, causing a plasma to be created and maintained. The axial magnetic field confines the plasma to the center regions of the discharge tube, away from the walls, so as to form a plasma column.

Abstract: A segmented coaxial laser shell assembly having at least two water jacket sections, two pairs of interconnection half rings, a dialectric break ring, and a pair of threaded ring sections. Each water jacket section with an inner tubular section that defines an inner laser cavity with water paths adjacent to at least a portion of the exterior of the inner tubular section, and mating faces at the end of the water jacket section through which the inner laser cavity opens and which defines at least one water port therethrough in communication with the water jackets. The water paths also define in their external surface a circumferential notch set back from and in close proximity to the mating face. The dielectric break ring has selected thickness and is placed between, and in coaxial alignment with, the mating faces of two of the adjacent water jacket sections.

Abstract: The improved longitudinal discharge laser electrode with IR baffle includes an electrode made up of washers spaced along the laser axis in order to form inter-washer spaces for hollow cathode discharge to take place and for IR radiation to be trapped. Additional IR baffles can be placed between the electrode ann the window.

Abstract: The present invention provides a novel ion-laser tube possessive of a high output characteristic. The ion-laser tube includes an improved slender discharge tube made of silicon carbide possessive of a high resistivity to sputtering caused by high energy ions and electrons involved in a large discharge current. The improvement in the novel ion-laser tube over the prior art manifests in the discharge tube having an inner wall surface possessive of a small roughness, typically approximately 4 micrometers or smaller. Such small roughness in the inner wall surface of the discharge tube is possessive of preventing silicon carbide molecules existing in the inner wall surface thereof to be sputtered by high energy ions and electrons involved in the large discharge current. As a result of those, the novel ion-laser tube is free from a substantial reduction of laser output.

Abstract: The IR baffles placed between the window and the electrode of a longitudinal discharge laser improve laser performance by intercepting off-axis IR radiation from the laser and in doing so reduce window heating and subsequent optical distortion of the laser beam.

Abstract: The invention provides an ion laser tube in which a TiC or B.sub.4 C coating layer having excellent durability to plasma bombardment and an alumina coating layer for preventing oxidation of TiC and B.sub.4 C are provided on an inner face of a central hole in an SiC capillary member, whereby stability to electric discharge or plasma bombardment increases and properties of the ion laser tube are stabilized. Thus, the sputtering resistance is improved and degradation of the laser properties is suppressed.

Abstract: A structure for holding tubular cathode in a gas laser tube. The cathode is provided at one end with a slender projection inserted into a hollow member attached to one sealing flush member and caulked at a groove formed in the hollow member to hold the cathode. The cathode is also provided with spring plate members at the other end. A slender discharge tube is provided with an expanded portion serving as a discharge chamber, the expanded portion having a smaller diameter than the cathode and pressing against the spring plate members. The spring plate members securely hold the cathode within the gas laser tube without melting or cracking at the sealing flush members during welding.

Abstract: An apparatus and method of fabricating an tubular reflector for use in a laser. The tubular reflector is formed by first grinding smooth the inside surface of a round metal tube. The polished tube is inserted into an elliptical mold. The mold is then pressed to shape the round tube into an elliptical tube. Next the inner wall of the tube is coated with a highly reflective material. Finally, a light source and a laser rod are positioned in the tube such that after the light source is turned on, light is reflected off the reflective walls of the tube to the laser rod resulting in laser light emitting from the ends of the rod. It may also be preferable that the elliptical tube be formed by combining and bending two flat metal sheets.

Abstract: A saturable reactor comprising a magnetic core (1) having an annular or an elongated race-track configuration, an electrical insulator (6) disposed around the magnetic core and a conductor winding (3) wound around the insulator (6). A coolant duct (7) is provided in the insulator to extend radially transversely across the magnetic core and having a radially separated inlet and outlet (8,9). A saturable reactor may comprises an annular magnetic core (51), a conductor winding including a first conductor (55) surrounded by the magnetic core (51) and a second conductor (56) disposed around the magnetic core and connected to the first conductor (55) through a load. A control winding (54) extends through the first and second conductors (55,56), and at least one of the first and second conductors (55,56) has a notch or a through hole (57,59) for insulatingly receiving the control winding (54) therein.

Abstract: A heat conducting structure in a discharge tube of an ion laser, that has high resistance to erosion due to sputtering comprises a discharge limiting member having an inner aperture, and a thin film of refractory ceramic coating areas near the inner aperture. The thin film of ceramic does not significantly retard heat flow out of the discharge into the heat conducting structure, but significantly increases resistance of the heat conduction structure to sputtering.

Abstract: The present invention provides a heat-resistant electrical insulator adapted for joining laser housing portions, which insulator comprises: an annulus; a channel in the annulus traversing the circumference and length of the housing; at least two ports, each communicating with the channel and an outer surface of the housing; and an attachment for securely attaching each end of the annulus to a laser housing member.

Abstract: A disk, or heat web, is generally circularly shaped, and has a circumferential lip normal to the plane of the disk. A split ring, fabricated from a material having a low co-efficient of thermal expansion fits within the circumferential lip. A generally circularly shaped expansion member, made from a material having a relatively high coefficient of thermal expansion, fits within the split ring. A suitable brazing material is placed between the split ring and the circumferential lip of the disk. The heat produced by the brazing process expands the split ring and allows it to be brazed into place when the assembly is placed on the inside of the cylindrical member.

Abstract: An improved electrode design for reducing discharge instability, especially in white light lasers. The apparatus consists of at least one cathode electrode (12) arranged between anode electrodes (14), said cathode being divided into two equally long tube parts (15) designed with inner cylindrical electrode surfaces (A.sub.1, A.sub.2) between which a widened portion (16) is located and each anode electrode is connected via and insulator (13) to the end of each tube part (15) facing away from the widened portion. This widened portion of the cathode serves to divide the cathode which in turn stablized the current and the current density. It can also serve as a metal reservoir.

Abstract: An ion laser is constructed with means for generating a magnetic confinement field operating in the cathode transition region of the laser. The magnetic confinement field is preferably generated by first and second magnetic windings, each axially aligned with the laser volume, but disposed so as to generate first and second magnetic fields which are of opposite polarity. The first and second magnetic fields of opposite polarity combine to create a region of zero axial magnetic field, which in a preferred embodiment is located substantially within the cathode transition region of the laser. In an alternate embodiment, the first and second magnetic fields are of the same polarity, and therefore generate a region of minimized axial magnetic field, preferably located substantially within the cathode transition region of the laser.

Abstract: Metal vapor laser apparatus includes an envelope within which is contained electrodes and a plurality of cylindrical copper segments arranged between them. During operation of the laser, bromine and helium buffer gas are arranged to flow through the envelope, causing copper bromide to be produced. When a discharge is established between the electrodes, the copper bromide vaporizes and dissociates to give copper vapor which is then excited to produce a population inversion. Such apparatus is able to operate at relatively low temperatures, in the region of 600.degree. C.

Abstract: A gas laser with a discharge bore defined by a single-bore extruded ceramic discharge tube is disclosed. An outer tube is located over the discharge tube so as to define an annular space therebetween. Caps are located over both ends of the tubes and each cap is provide with at least one gas transport passage so the discharge bore and the annular space are in communication. The annular space is filled with electrically insulating, thermally conducting components such as washers, baffles and ceramic granules. When the laser is in operation the annular space serves as a gas return path so a uniform equilibrium pressure is maintained in the discharge bore. The components in the annular space inhibit the flow of electrical current in the space so all of the current flow is through the discharge bore so as to excite the gas therein. The components in the annular space also provide a thermally conductive path between the discharge tube and the outer tube to diffuse heat away from the discharge bore.

Abstract: Laser apparatus includes a gas filled tube and is arranged to act as a switch to trigger, within the tube itself, a discharge. The power dissipated in the discharge is applied to material which forms, or is to form, a laser amplifying medium, to provide pumping power. Thus, no external switch, such as a thyratron, is required, unlike conventional laser arrangements.

Abstract: Several gas-tight enclosures share a common optical cavity. The enclosures may be filled with neat gases or mixtures of gasses. The same gas or mixture, at the same or a different pressure, may occur in more than one enclosure. The gas or gasses in the various enclosures may be pulsed to lase in any desired sequence, simultaneously, or in any combination.