Abstract: A capacitor using a dielectric film wherein plural capacitor units each including one or two capacitor elements are formed on an insulator upper electrodes of at least two capacitor elements of different capacitors units are electrically connected. Each of the capacitors includes a lower filmy electrode, a dielectric film formed on the lower filmy electrode, and an upper filmy electrode formed on the dielectric film. Since plural capacitor units are suitably connected to have desired characteristics, a great deal of flexibility is realized.

Abstract: A method of forming and inspecting beam drilled holes, and in particular laser beam drilled holes, in an article, such as a turbine blade or vane airfoil, with a hollow interior. The method includes (a) filling the hollow interior with a beam blocking material having fluorescent material, (b) beam drilling the holes in the wall through to the hollow interior, and (c) inspecting the hole under an ultraviolet light. The beam blocking material preferably includes a wax material and step (a) includes filling the hollow interior with a melted mixture of the wax and fluorescent materials. The wax material may be a pattern wax material suitable for use in making turbine blade investment casting molds and the fluorescent material may be a fluorescent penetrant.

Abstract: An electron beam processing apparatus imparted with capability of preventing occurrence of a failure in welding or the like processing of a workpiece by automatically compensating for changes in a focused position of an electron beam ascribable to time-dependent consumption of a rod-like cathode. The apparatus includes a bias voltage detecting circuit for monitoring a bias voltage applied to the rod-like cathode electrode and an automatic lens-current correcting circuit for controlling lens currents flowing through focusing coils by referencing experimentally obtained relations between the bias voltage or cathode temperature and lens current such that change of the position of the focal point can be nullified.

Abstract: A laser processing method locates a processing head at a piercing start position so that the focal point of the laser beam is positioned above the workpiece surface and offset from a point right above the intended piercing point on the workpiece. While conducting irradiation with the laser beam and jetting of an assist gas, the processing head located at the piercing start position is moved simultaneously both in a direction parallel to the workpiece surface and a direction perpendicular to the workpiece surface such that the focal point approaches the piercing point.

Abstract: A Laser beam machining is carried out by irradiating beforehand the laser beam along a final locus for a main machining, under such a condition as to obtain an energy density for forming a groove angled to a surface of a work. Thereafter, the laser beam is irradiated to the groove, while changing only the energy density according to a cutting condition to cut the work.

Abstract: A method of providing a body of material (14), having a thermal conductivity approximately equal to that of glass, with a sub-surface mark. A beam of laser radiation (12) to which the material (14) is substantially opaque is directed to surface of the body, so as to cause beam energy to be aborbed at the surface of the material in an amount sufficient to produce localised stresses within the body (14) at a location spaced from the surface without any detectable change at the surface, the localised stresses thus produced being normally invisible to the naked eye but capable of being rendered visible under polarised light.

Abstract: Detecting light from a detecting light source (122) is irradiated to a workpiece (1) and the reflected light is detected by a photosensor (126). At the same time, light resulting from emission of plume produced upon laser processing is also detected by the photosensor (126). A laser controller (26) binary-codes a detection signal from the photosensor (126) to provide a rectangular wave signal (TP) and, based on the rectangular wave signal (TP), generates a trigger signal (TP.sub.2) for oscillating a processing laser beam. At this time, the trigger signal (TP.sub.2) is fed back to generate a gate signal (GP) and, based on the gate signal (GP), the detection signal resulted from the emission of the plume is omitted in the gate circuit (245) to produce a trigger signal (TP.sub.G). This trigger signal (TP.sub.G) is given with a delay time (T.sub.D) to produce a trigger signal (TP.sub.1). The above trigger signal (TP.sub.2) is generated in synch with the trigger signal (TP.sub.1).

Abstract: Oxygen and nitrogen contained in air is separated by an air separator. The separated nitrogen gas is supplied to an optical path cover of a laser beam machine as a protective gas for bend mirrors. Further, the separated nitrogen gas or oxygen gas can be selectively supplied to a laser beam head as an assist gas. The purity of the separated nitrogen gas can be kept within a predetermined range (94 to 99.5%) on the basis of a difference in pressure between a first conduit for supplying nitrogen gas and a second conduit for supplying oxygen gas. It is preferable to provide a filter for removing dust from air supplied to the air separator and a second filter for removing oil mist from the separated nitrogen supplied to the optical path cover.

Abstract: Apparatus for treating a material having a miniaturized photoionic head including at least one optical fiber (2), a pulsed light source permitting the treatment of the material (10), a light injector for injecting light into one end of the fiber and a miniaturized photoionic head (8) having a ring (16). One side of the ring is fixed to the other end of the fiber, and the other side of the ring is against the material. This ring confines a plasma forming, due to the pulsed light, in the space defined by the ring, from a material or a substance (20) placed in the space, for the treatment of the material such as surface treatment of metals.

Abstract: Apparatus and methods for decorating a gemstone with colored indicia so that the indicia is readily visible from an exterior surface of the gemstone. The indicia is engraved on an predetermined exterior surface portion of the gemstone. The exterior surface on which the indicia is engraved may be the exterior surface from which it is visible, or another surface. The gemstone may be semi-precious, man-made, or precious, and can be faceted or cabochon. The indicia is engraved in the exterior surface by a laser beam. The laser beam is directed to the exterior surface, while the gemstone is held in a manner so that a significant portion of the laser beam is precluded from reflecting internally within the gemstone, thereby ensuring that the gemstone is not damaged by the laser beam. Once engraved a colored inlay, e.g., paint, is provided in the engraved recess to complete the decorative indicia.

Abstract: A thin film conductive line is formed between MR pads on an MR head for protecting an MR sensor from electrostatic discharge (ESD) during assembly steps between row level fabrication of the head and prior to merge of a head stack assembly with a disk stack assembly. The conductive line may have a reduced thickness delete pad. A laser beam having a fluence sufficient to sever the conductive line at the delete pad but insufficient to damage or cause debris from structure underlying or surrounding the conductive line is used to sever the conductive line.

Abstract: An image display method for a liquid crystal mask marker displays an image of a high sharpness even when the marking speed is high. To this end, when the display image of a liquid crystal mask (4) is to be rewritten, the method includes performing at least one of (a) making all of the opaque picture elements (B) of the current image (P1) to become transparent, and (b) making all of the transparent picture elements (A) of the current image (P1) to become opaque; then making the electrodes of all of the picture elements (A,B) to be grounded or set equipotentially; and then starting the display of the next image (P2).

Abstract: A laser beam machining method is disclosed which makes it possible to cut a mild steel sheet or the like at a higher speed. A condenser lens (10a) is arranged within a machining head (10). A laser beam (11) is converged by this condenser lens (10a) and irradiated onto a workpiece. The machining head (10) has an assist gas inlet port (10b) formed through one side wall thereof, to which are connected an oxygen gas cylinder (90) and an inactive gas cylinder (91). The gas supplied via the assist gas inlet port (10b) is delivered as a jet toward the workpiece through the nozzle at the tip of the machining head (10). The oxygen gas cylinder (90) and the inactive gas cylinder (91) are provided with respective electromagnetic valves (90a) and (91a) of which the opening and closing can be electrically controlled. To cut the workpiece, a saturated cutting speed of the workpiece is determined in advance by an experiment or the like.

Abstract: An improved laser processing head comprising a housing, a lens holder-nozzle mounted within the housing and a gas distributor for introducing gas adjacent a focusing lens retained within the housing to cool the lens and prevent the lens from becoming contaminated or damaged from material ablated from the workpiece. The gas distributor is comprised of a plurality of angled distribution slots that creates a vortex gas flow action directed away from the face of the lens and towards the nozzle outlet.

Abstract: An on the fly method of laser shock peening a gas turbine engine part by continuously moving a metallic gas turbine engine part while continuously firing a stationary laser beam, which repeatably pulses between relatively constant periods, on a portion of the part with sufficient power to vaporize material on the surface of the portion of the part with the pulses around laser beam spots formed by the laser beam on the surface and form a region having deep compressive residual stresses extending into the part from the laser shock peened surface. Flowing a curtain of water over the surface upon which the laser beam is firing while moving the part until the laser shock peened surface is completely covered by laser beam spots at least once. The surface may covered by a paint which is then the material used to produce the plasma or the surface may be unpainted and the metal of the part is used to produce the plasma.

Abstract: A laser cutting machine having a cutting head that is positionable in X-, Y- and Z-directions and which comprises a laser oscillator for supplying a beam via a plurality of mirrors to the cutting head and onto a workpiece mounted on a flat table surface with rising rollers or a retractable rotatable support in the table. The locations and center-of-gravity positions of the machine components are disposed for optimum maneuverability and balance. The plurality of mirrors in the optical system have a first bend mirror, that is a precision-adjustable, circular-polarizing mirror, and a plurality of subsequent bend mirrors that are disposed to counterbalance any resulting phase shift amounts. The subsequent mirrors can be ES or PS coated mirrors and can be accompanied by convex, concave, collimating, etc. mirrors and lenses as needed. A collimation device ensures proper focusing of the beam over a wide movable range.

Abstract: Apparatus and methods for engraving indicia on gemstones and the gemstones created thereby. The indicia may be either decorative indicia, readily visible to the naked eye, or identification indicia, invisible to the naked eye, and is engraved on or adjacent a predetermined exterior surface portion of the gemstone. The gemstone may be semi-precious, man-made, or precious and has another exterior surface portion for engagement by a portion of the apparatus. The apparatus basically comprises a support for supporting the gemstone and laser device for generating a laser beam and for directing it beam to the predetermined exterior surface of the gemstone to engrave the indicia therein. The support is constructed to engage the other exterior surface portion of the gemstone in such a manner that a significant portion of the laser beam is precluded by the support from reflecting internally within the gemstone, thereby ensuring that the gemstone is not damaged by the laser beam.

Abstract: An image heating apparatus includes a heater includes an electrically insulating base plate, an electrically resistive layer, on the base plate, for generating heat when supplied with electrical power, and a terminal electrode for connection with the resistance layer, including a silver alloy layer, and a conductive layer having a lower resistance value than the silver alloy layer; a film for transmitting the heat from the heater to heat an image on a recording material while being moved together with the recording material, sliding on the heater; and a power supply connector press-contacted to the silver alloy layer with a predetermined contact pressure.

Abstract: A method of machining a blind slot 3 in a workpiece 2 comprises heating the surface of the workpiece 2 above its melting temperature with, for example, a beam of laser energy and directing at least two gas streams 5, 6 such that they together with the base of the slot 3, create a vortex having a predetermined rotational direction for removing molten material from the slot 3.

Abstract: The invention relates to a laser marking method in which a laser beam is used for raster scanning of a liquid-crystal mask, on which a desired marking pattern is formed and the laser beam passing through the liquid-crystal mask gives a marking to an object. A marking pattern on the liquid-crystal mask is successively switched over to a subsequent marking pattern every scanning line, to reduce variation in transmissivity of the liquid-crystal mask, thereby obtaining marking with less unevenness of image.