Abstract: When laser welding is performed by irradiating a laser beam to a objected joint portion of metals adjacently arranged, the irradiation of the laser beam is terminated after power of the laser beam is reduced in comparison with an irradiation starting time without constantly setting the power of the laser beam from the irradiation start to the irradiation termination. When the power of the laser beam is constant from the irradiation start to the irradiation termination, the metals melted by the irradiation of the laser beam are suddenly cooled and solidified by the irradiation termination of the laser beam so that various problems are caused. In contrast to this, the sudden cooling solidification of the molten metals can be restrained by terminating the irradiation of the laser beam after the power of the laser beam is reduced. Thus, it is possible to reduce the generation of a crack and an air bubble in a welding portion. Further, residual stress of the welding portion can be reduced and restrained.

Abstract: Predictive models of physical parts of the laser processing system part determined. These predictive models are used to determine how the physical system will actually react. The predicted reaction from the models is used as feedback in order to produce the control signals. These physical models therefore adjust to the operation of the system, much in the way that actual feedback would adjust the operation of the system. However, the system may be used at faster speeds, where the actual feedback could not be produced fast enough. Different kinds of modeling are described, including in-position feedback which models sharp movements of the laser system, trajectory models which superimpose the commanded curve over the predicted actual curve to determine errors in trajectory, and constant/variable energy density controls.

Abstract: The present invention relates to a method for marking metallic alloys using laser alloying. Specifically, the present invention is directed toward the use of laser alloying steel or aluminum alloys with a mark that provides protection against wear and corrosion and greater permanency.

Abstract: A number of new laser patterns are defined by laser scribing the material. This produces new laser patterns which have not previously been known.

Abstract: An EOM Q-switched CO2 laser produces bursts of laser pulses delivered at a high PRF such as 20-140 kHz and having a short high-power spike of about 80-150 ns followed by a lower-power tail of about 0.05-12.0 &mgr;s. The bursts and/or laser pulses can be shaped by controlling the RF pumping duty cycle, the delay between the onset of RF pumping and the initiation of Q-switching, the pulse repetition frequency, and/or the duration of the tail. The bursts of laser pulses can be adapted to facilitate machining of metal layers and/or layers containing materials having disparate vaporization temperatures and/or disparate melting points, such as FR4 or green ceramics.

Abstract: A method of repairing a disconnected wiring, which has a step of connecting a main wiring in which disconnection is caused and a spare wiring which is formed on or under the main wiring via an interlayer insulating film in their intersecting region of the main and spare wirings, comprising the steps of opening a hole by irradiating a laser beam of a first output intensity from a laser to the intersecting region of the main wiring and the spare wiring, and connecting the spare wiring and the main wiring by melting a part of the spare wiring and the main wiring by irradiating a laser beam of a second output intensity, which is different from the first output intensity, toward the hole.

Abstract: The present invention relates to the use of a laser to remove surface contamination and oxidation from a ball grid array substrate. The laser etching can be configured to cover the entire substrate or pinpointed to the epoxy molding compound/solder resist (EMC/SR) interfaces. Additionally, a laser can be used to roughen the surface of a substrate to provide better adhesion when attaching the die to the substrate.

Abstract: It is an object of this invention to provide a laser piercing method capable of reducing the time required for piercing a workpiece and satisfactorily forming a pierced hole.

Abstract: A method and system for processing at least one microstructure which is part of a multi-material device containing a plurality of microstructures is provided. The at least one microstructure has a designated region for target material removal. The method includes generating a laser beam, modifying the laser beam to obtain a modified laser beam, and sequentially and relatively positioning the modified laser beam into at least one non-round spot having a predetermined non-round energy distribution on the designated region to remove the target material in the designated region. The predetermined non-round energy distribution covers an area of the designated region such that energy is more efficiently coupled into the designated region for the non-round energy distribution than energy coupled into the designated region for a round energy distribution covering the same area.

Abstract: A method for manufacturing an ink jet head. In a thick film laminating step, a patterning layer corresponding to the configuration of ink flow paths on a member provided with a pressure generating source is formed, and an inorganic material layer is overcoated on the patterning layer to form an ink discharge surface. A patterned image of a predetermined ink discharge port configuration is irradiated by a laser capable of completing a sublimate ablation process before the laser beams are dispersed in a work piece as thermal energy. Subsequently, the sublimate ablation process is executed on ink discharge ports almost simultaneously from the inorganic material layer on the ink discharge side up to the interior of the thickness of the patterning layer. The patterning layer is removed after processing the ink discharge ports.

Abstract: A method for altering a circuit pattern of a printed-circuit board includes the steps of removing a portion of the printed-circuit board so that the circuit pattern inside the printed-circuit board is exposed, and connecting an exposed portion of the circuit pattern to another portion of the printed-circuit board by a conductive body so that a circuit path is formed between the exposed portion of the circuit pattern and the other portion of the printed-circuit board.

Abstract: A quasi-CW diode- or lamp-pumped, A-O Q-switched solid-state UV laser system (10) synchronizes timing of the quasi-CW pumping with movement of the positioning system (36) to reduce pumping while the positioning system (36) is moving from one target area (31) to the next target area (31) to form multiple vias in a substrate at a high throughput. Thus, the available UV power for via formation is higher even though the average pumping power to the laser medium (16), and thermal loading of the laser pumping diodes (14), remains the same as that currently available through conventional CW pumping with conventionally available laser pumping diodes (14). The quasi-CW pumping current profile can be further modified to realize a preferred UV pulse amplitude profile.

Abstract: A method of lasing a filler wire to weld a first workpiece to a second workpiece comprising first and second materials, respectively, includes positioning a tip of the filler wire above an opening defined by the workpieces. The tip extends over a width of the opening and over a portion of each of the workpieces. The filler wire is preheated and melted by directing a laser beam at the tip. The laser beam is advanced along a length of the opening with the tip positioned under the laser beam to form a high aspect ratio weld between the workpieces. The high aspect ratio weld has an aspect ratio of at least about two. The energy and time required for the laser beam to melt the filler wire is reduced as the filler wire is preheated.

Abstract: There is described a laser processing device (1) whereby, by means of laser light (6), a workpiece (4) can be processed and wherein, at the same time, an image of the workpiece (4) to be processed is obtained, wherein the focusing of the imaging optics is independent of the focusing of the laser optics. The device (1) comprises a stationary laser mirror (21) and laser focusing optics (22), which laser focusing optics (22) are axially displaceable relative to the laser mirror (21). The device (1) further comprises imaging optics (23) which are al axially displaceable relative to the laser mirror (21), such that the axial distance between the laser focusing optics (22) and the imaging optics (23) is constant.

Abstract: A laser printing apparatus is formed by a laser oscillator 10, galvano mirrors 42, 44 for scanning the laser light emitted from the laser oscillator 10, and an f&thgr; lens 40 for focusing the laser light emitted from the laser oscillator 10 on MCCs 32, 34 serving as the member to be printed. The laser oscillator 10 is an YLF laser oscillator which emits the laser light of the third harmonics in the ultraviolet range. The laser printing is performed on the MCCs 32, 34 serving as the member to be printed by using the laser light emitted from the laser oscillator 10.

Abstract: Motorized slides are inserted between the end of a robot arm and a robot tool/sensor arrangement to provide additional positioning ability. A control unit of the slides cooperates with the control unit of the sensor to maintain the tool correctly positioned over a feature while the robot arm moves following a programmed path. The control unit of the sensor has look-ahead and additional buffers from which corrected information is determined to compensate for robot teaching inaccuracies, calibration and robot arm response errors. A sensor with two distinct probing zones is used to get information about the position of the tool tip and of the feature to assist in calibrating the sensor/tool relation.

Abstract: Each one of multiple laser sources are independently separately mounted on a laser material processing platform and their beam paths are combined by a combiner which includes one or more optical elements mounted in the laser material processing platform which make the beam paths parallel and colinear. The combined beams are then moved in X and Y planes relative to a workpiece supported in the laser material processing platform under the control of a computer in the performance of work in accordance with a work program. The beam path of each laser source and the optical axis of the beam delivery system are each pre-aligned to the same predetermined reference and automatically coincide upon installation such that these components are rapidly and interchangeably interfaceable. The beams are orthogonally polarized and the optical elements of the combiner transmit one beam while reflecting another beam. While two laser beams are shown, an infinite number of laser beams may be used.

Abstract: A workpiece, designed as a printed circuit board for example, can be moved by means of a transport device under a laser unit in such a way that a region to be machined of the workpiece passes into the deflecting region of the laser beam. The workpiece is set between clamping jaws to a vertical position in which the laser beam is focused exactly on that surface of the workpiece which is to be machined. As a result, the machining accuracy can be considerably increased.

Abstract: Method of laser welding which comprises at least two steps: a first step wherein the laser (10) is operated for some time T1 at low intensity in order to create a melt (31) in one part (12) with little or no evaporation of matter, thereby reducing product contamination, and a further step wherein the laser is operated for a shorter time T2 at high intensity in order to push said melt (31) towards a further part (13), whereby large gaps between said parts can be bridged, yet further reducing product contamination thanks to the low laser energy needed to proceed with the further step. Optionally, a third step is performed during a third period of time (T3) in which the weld is post-heated.

Abstract: The process for manufacturing an electronic circuit includes disposing an electronic device on a circuit substrate and hot melting a solder formed on the electronic device or the circuit substrate to bond the electronic device and the circuit substrate. The process includes the steps of feeding a liquid onto lands on the circuit substrate, aligning and mounting the electronic device on the lands, placing the circuit substrate in a treating vessel and heating the circuit substrate. The heating step includes controlling a pressure of an atmosphere in the treating vessel, hot-melting the solder to prevent at least a portion of the liquid from evaporating until the electronic device and the circuit substrate are bonded and to permit the liquid to evaporate after the electronic device and the circuit substrate are bonded.

Abstract: A method and apparatus are provided for forming shapes and contours in metal sections by generating laser induced compressive stress on the surface of the metal workpiece. The laser process can generate deep compressive stresses to shape even thick components without inducing unwanted tensile stress at the metal surface. The precision of the laser-induced stress enables exact prediction and subsequent contouring of parts. A light beam of 10 to 100 J/pulse is imaged to create an energy fluence of 60 to 200 J/cm2 on an absorptive layer applied over a metal surface. A tamping layer of water is flowed over the absorptive layer. The absorption of laser light causes a plasma to form and consequently creates a shock wave that induces a deep residual compressive stress into the metal. The metal responds to this residual stress by bending.

Abstract: A method of laser machining using an ultra-fast pulse laser is presented. According to the present invention a plurality of holes with a pitch less than the wavelength of the laser are drilled into a material sample. Reliable and reproducible hole drilling is accomplished through an exemplary drilling sequence which applies a number of pulses at a first pulse energy to the surface spaced to avoid laser hardening of the surface for adjacent holes of a first set of holes. Next, the number of pulses is increased or the energy of the laser beam is increased to drill holes that are interstitial to the first set of holes. The exemplary laser machining process may used to produce both one-dimensional and two-dimensional photonic crystals, among other applications.

Abstract: A monitor of a plurality of optical signals utilizing fiber optics which form an array. An image of the array is captured and the captured image is processed for detecting a quality of an optical signal such as the presence, absence, intensity, wavelength, or other quality of the optical signal. A method of monitoring a plurality of optical signals by capturing a plurality of optical signals from an array of signals and detecting a quality of at least one optical signal is also disclosed.

Abstract: When a laser beam is focussed onto a substrate for the purpose of substrate processing, the optical units such as beam expander, deflecting unit, and optical imaging device prescribe the range of depth of focus in which it is possible to work with a minimum spot size. The difficulty of boring thin holes, especially in thick substrates, is overcome with a second laser beam that is widened via a second beam expander and likewise focused onto the substrate via the deflecting unit and the optical imaging device. The position and the length of the second range of depth of focus can be varied by selecting the magnification of the second beam expander or by maladjustment. Thin holes can also be bored into thick substrates by using the two laser beams one after another.

Abstract: A method of laser machining using an ultra-fast pulse laser is presented. According to the present invention a plurality of holes with a pitch less than the wavelength of the laser are drilled into a material sample. Reliable and reproducible hole drilling is accomplished through an exemplary drilling sequence which applies a number of pulses at a first pulse energy to the surface spaced to avoid laser hardening of the surface for adjacent holes of a first set of holes. Next, the number of pulses is increased or the energy of the laser beam is increased to drill holes that are interstitial to the first set of holes. The exemplary laser machining process may used to produce both one-dimensional and two-dimensional photonic crystals, among other applications.

Abstract: For the laser machining of organic materials, a laser with the below listed parameters is used. The laser has a wavelength of 300 nm to 1200 nm, a pulse width of >50 ns and a pulse frequency of ≧20 kHz. To increase a degree of absorption and consequently the machining rate, additives with good absorption of the laser beam with the respectively chosen wavelength are admixed with the organic materials.

Abstract: A method of laser machining using an ultra-fast pulse laser is presented. According to the present invention a plurality of holes with a pitch less than the wavelength of the laser are drilled into a material sample. Reliable and reproducible hole drilling is accomplished through an exemplary drilling sequence which applies a number of pulses at a first pulse energy to the surface spaced to avoid laser hardening of the surface for adjacent holes of a first set of holes. Next, the number of pulses is increased or the energy of the laser beam is increased to drill holes that are interstitial to the first set of holes. The exemplary laser machining process may used to produce both one-dimensional and two-dimensional photonic crystals, among other applications.

Abstract: A process for precision patterning or cutting of a sheet stock, such as an adhesive tape, includes the step of irradiating a surface of a sheet stock with an irradiation source to pattern or cut a part in the sheet stock and adjusting at least one of a beam width and the power of the irradiation source to form a cut in the sheet stock to a controlled depth. The method is particularly useful for precision cutting adhesive members, such as adhesive fluid seals, for an inkjet print cartridge.

Abstract: A laser amplifier for laser shock processing having a pump cavity supplying photons at selected or variable wavelengths and orientations to that of the gain medium present therein. In one embodiment, the pump wavelength is substantially equal to a corresponding wavelength difference between the upper laser state energy level and the ground state energy level of atoms composing the gain medium. In an alternate embodiment, photonic energy is applied asymmetrically to the gain medium to produce a desired spatial energy profile. The pump cavity may comprise an alexandrite laser or a diode laser system. Depending on the type of pump cavity, the photonic energy is applied to the gain medium either longitudinally or transverse to the laser beam axis of traversing therein.

Abstract: A method of drilling a circuit substrate. A circuit substrate including at least a core layer and a metal layer covering one or both surfaces of the core layer is provided. A half-etching process is performed by etching the metal layer on the circuit substrate with an etchant to reduce the thickness of the metal layer. A surface treatment on the surface of the metal layer A via is formed in the circuit substrate by laser.

Abstract: In a laser beam machining method for a wiring board, a machined portion of the wiring board is irradiated with a pulsed laser beam for a beam irradiation time ranging from about 10 to about 200 &mgr;s and with energy density of about 20 J/cm2 or more, thereby machining the wiring board, for example, drilling for a through-hole and a blind via hole, grooving, and cutting for an outside shape.

Abstract: Method for welding coated sheets with a laser beam in which an energy beam is directed on a welding zone of the sheets and is adapted to drive the coating steam vapor outward. The invention is particularly applicable in the field of vehicle manufacturing.

Abstract: This invention is directed toward a method of calculating the total laser energy needed to produce one or more selected laser induced surface modification reactions in a substrate moving relative to a laser beam. The present invention is further directed to a method for programming a programmable feedback control system with the calculated total laser energy such that the control system may be used to control laser beam power level and beam width in a process for producing a laser induced surface modification.

Abstract: An energy beam method and apparatus for processing a workpiece is accomplished by making the energy density per unit time and unit area of the energy beam proportional to the traveling velocity of the workpiece. This is accomplished by adjusting the frequency, irradiation power, or duty cycle of the energy beam. The travel velocity of the workpiece is measured by using a linear scale to generate pulse signals, calculating a traveling velocity based on the pulse signals and generating a pulse signal, dividing the pulse signals output by the calculation step, and generating a trigger signal in response to the pulse signals created by the dividing step to drive an energy beam irradiation device (such as a laser generator) to output the energy beam.

Abstract: A laser comprising a master oscillator and a loop phase conjugate mirror (Loop-PCM) for substantially eliminating transient relaxation oscillations to instead form controlled sustained pulsations. In a preferred embodiment suitable for material processing applications with high power requirements, the master oscillator is part of a Phase Conjugate Master Oscillator Power Amplifier (PC-MOPA). A method for processing a material using a Loop-PCM by determining and using an optimal pulse fluence, duration and spacing is provided. Using pulses of the kind which are produced by the transient, and normally not desirable, relaxation oscillations common to Nd:YAG and other lasers, relaxation oscillations with controllable pulse duration, repetition rate and duty cycle are generated, making it ideal for materials processing.

Abstract: The present invention is to provide a novel laser welding method, capable of preventing formation of a welding defect, and achieving a deep penetration by a low heat input so as to enable formation of a welding structure with a high strength and a high toughness even in the case of welding by a high power laser. A welding operation is executed with a periodical fluctuation adjustment so as to have a base output of 50% or more with respect to a peak output.

Abstract: A laser processing method is presented for processing a circuit board including at least two layers, having a conductive layer with a plurality of holes disposed on a surface layer of insulating layer to be processed by applying laser beam to an insulating layer corresponding to holes of the conductive layer. In this laser processing method or apparatus, a circuit board is irradiated with a laser beam, and a reflected laser beam is detected, whereby the laser process of the insulating layer corresponding to an abnormal hole in the conductive layer is stopped, if the detected value of the reflected laser beam is an abnormal value out of a desired value. Also in this laser processing method or apparatus, the insulating layer corresponding to the hole is processed when the detected value of the reflected light conforms to the desired value.

Abstract: A method of forming cooling holes in a gas turbine engine component. The method includes the steps of forming a hole in the component extending between a first surface of the component and a second surface of the component opposite the first surface and supplying pressurized air to the hole from the second surface of the component. The method also includes the step of sensing a parameter representative of air flow through the hole. Further, the method includes enlarging the hole until the sensed parameter represents a preselected air flow rate through the hole.

Abstract: A burst (50) of ultrashort laser pulses (52) is employed to sever a conductive link (22) in a nonthermal manner and offers a wider processing window, eliminates undesirable HAZ effects, and achieves superior severed link quality. The duration of the burst (50) is preferably in the range of 10 ns to 500 ns; and the pulse width of each laser pulse (52) within the burst (50) is generally shorter than 25 ps, preferably shorter than or equal to 10 ps, and most preferably about 10 ps to 100 fs or shorter. The burst (50) can be treated as a single “pulse” by conventional laser positioning systems (62) to perform on-the-fly link removal without stopping whenever the laser system (60) fires a burst (50) of laser pulses (52) at each link (22). Conventional wavelengths or their harmonics can be employed.

Abstract: A method of making a small-diameter through hole having high reliability with regard to a hole wall at a high rate with the energy of a high-output carbon dioxide gas laser without pre-making any hole in a copper foil, forming or disposing a coating or a sheet of an organic substance containing 3 to 97% by volume of at least one powder selected from the group consisting of a metal compound powder, a carbon powder and metal powder which have a melting point of at least 900° C.

Abstract: The object of the present invention is to provide a low iron loss and low noise grain-oriented electrical steel sheet for securing both low core loss and low noise of a transformer at the same time.

Abstract: A method for manufacturing a liquid-discharging recording head can prevent deviation in the dimensions and the pitch of grooves, serving as liquid channels, and holes, serving as discharging ports, and generation of burrs around discharging ports while maintaining the grooves and the holes to desired sizes and without increasing a time required for the processing when forming the grooves and the holes by projecting a laser beam. In the method, when performing ablation processing of the liquid-channel grooves or the discharging ports in a top-plate blank by projecting the laser beam, the processing is performed by changing the energy density per unit time of the laser beam continuously or stepwise by adjusting the oscillation voltage or the oscillation frequency of the laser beam, attenuating the laser beam, or moving a substance to be processed along the optical axis.

Abstract: When drilling a multi layered sheet-like material, drilling is first made with pulses having energy that generates an inter-layer pull-off force smaller than the adhesion force between the layers. Then pulses with higher energy are radiated for trimming the shape of the holes, and thus through-holes having a desired shape are drilled without causing delamination of the layers.

Abstract: Cleaning a media surface, such as a disc surface, comprises subjecting the surface to a detector for sensing the nature of the surface for an irregularity in the smoothness of the surface. Directing, on detecting an irregularity beyond a predetermined amount, a burnishing pulse laser output to that irregularity, and energizing the laser to thereby impart an energy source to reduce the irregularity to a degree less than a predetermined amount.

Abstract: There is provided a glass-ceramic substrate for a magnetic information storage medium having a data zone and a landing zone capable of stably lifting a magnetic head in the landing zone and also capable of reducing the amount of lifting of the magnetic head in the data zone for realizing a high recording density. The landing zone has a multiplicity of projections or depressions formed by irradiation of laser beam. A CO2 laser or a laser diode pumped solid-state laser can be used for this purpose. The surface roughness (Ra) of a polished surface of the landing zone is within a range from 3 Å to 9 Å, height of the projections or depressions is within a range from 50 Å to 300 Å, surface roughness (Ra) of the projections or depressions is within a range from 10 Å to 50 Å and interval of the projections or depressions is within a range from 10 &mgr;m to 200 &mgr;m.

Abstract: A device for machining a hole or a shape of varying profile in a mechanical workpiece using an excimer laser comprises a screen having an aperture of predetermined shape disposed between the excimer laser and a device for focussing the laser beam, the screen being movable in a plane perpendicular to the laser beam. Control means is provided for automatically controlling displacement of the screen in real time while the hole is being machined in the workpiece, the control being effected as a function of the number of pulses emitted by the excimer laser. As an alternative, the screen may be replaced by a diaphragm comprising variable-aperture shutters.

Abstract: A laser joining system deforms a workpiece projection based on collapse of the projection to a predetermined displacement. The laser joining system has a laser system for generating a predetermined level of laser radiation based on radiation control signals. An actuation system directs the laser radiation to the projection and contacts the projection with a laser head based on forced control signals. The actuation system also generates position feedback based on a position of the laser head, wherein the position feedback includes a reference position of the laser head. The joining system further includes a controller communicating with the laser system and the actuation system. The controller generates the radiation control signals and the force control signals based on the position feedback. When the projection collapses to a predetermined displacement with respect to the referenced position, one of the radiation control signals causes the laser system to discontinue generation of the laser radiation.

Abstract: A method and apparatus for quality control of laser shock processing. The method includes measuring emissions and characteristics of a workpiece when subjected to a pulse of coherent energy from a laser. These empirically measured emissions and characteristics of the workpiece are correlated to theoretical shock pressure, residual stress profile, or fatigue life of the workpiece. The apparatus may include a radiometer or acoustic detection device for measuring these characteristics.

Abstract: A single pass actuator (70, 200), such as a deformable mirror (70), quickly changes, preferably in less than 1 ms, the focus and hence the spot size of ultraviolet or visible wavelength laser pulses to change the fluence of the laser output (66) at the workpiece surface between at least two different fluence levels to facilitate processing top metallic layers (264) at higher fluences and underlying dielectric layers (266) at lower fluences to protect bottom metallic layers (268). The focus change is accomplished without requiring Z-axis movement of the laser positioning system (62). In addition, the spot size can be changed advantageously during trepanning operations to decrease via taper, reduce lip formation, increase throughput, and/or minimize damage.

Abstract: The description relates to a procedure for fastening a carbide tooth (1) at a saw blade (2), with a carbide tooth (1) fabricated according to the saw tooth geometry being held butt-jointed to the prepared front-side abutting surface (3) of the saw blade (2) and then being attached to the saw blade under addition of heat along the joint (10) between the saw blade (2) and the carbide tooth (1). To create favorable process conditions it is suggested that the carbide tooth (1) is welded to the saw blade (2) by means a focal spot (9) of a laser beam (7) extending over the whole joint length.