Abstract: The invention is an apparatus and a method for drilling holes in a work piece with a laser. A laser beam is received by the optical system and directed along an optical path. The system directs the laser beam through a moveable mask aperture creating a sub-beam, that is reduced in size by a lens system as it is imaged onto a work piece. Multiple features are formed in the work piece by moving the mask.

Abstract: A photonic crystal comprising a waveguide made of material. The waveguide has a periodic set of holes. The material proximate to at least one of the holes in the periodic set of holes exhibits an index of refraction that has been modified by the application of laser energy relative to the material proximate to other holes in the periodic set of holes.

Abstract: A method for pre-calibration of a laser micro-machining system to achieve alignment tolerances greater than the diffraction limit of an illumination wavelength. A blank is mounted in the system, such that the beam spot is incident on its top surface. Two marks are ablated in the blank. The centers of the marks are a predetermined distance apart. The blank is illuminated with light and imaged with a digital camera. The resulting image is scaled such that each pixel has a width corresponding to a distance on the imaged surface, which is less than half of the illumination wavelength. The number of pixels between the centers of the marks determines this distance. The locations of the marks in the image are determined and a coordinate system is defined for surfaces imaged by the digital camera. Coordinates of the beam spot in this coordinate system are also determined using the second mark.

Abstract: A photonic crystal comprising a waveguide made of material. The waveguide has a periodic set of holes. The material proximate to at least one of the holes in the periodic set of holes exhibits an index of refraction that has been modified by the application of laser energy relative to the material proximate to other holes in the periodic set of holes. The photonic crystal is tuned to temporarily transmit a specific wavelength of light to create an on-off switch for the specific wavelength. Multiple photonic crystals are used to form a multiplexer and a demultiplexer.

Abstract: A laser drilling system for drilling holes in a work piece with a laser. The system includes: a laser for creating a laser beam and directing the laser beam along an optical path; a mask having at least one aperture, the mask and the aperture being located in the optical path to cause the creation of a sub-beam; a lens for forming a reduced-size image of the sub-beam onto the work piece and a translation stage for moving the mask to change the position of the sub-beam on the work piece. The laser beam has a wavefront cross-section with an area greater than the size of the aperture and is incident upon the mask and the aperture to create the sub-beam.

Abstract: A microcavity forming device is provided for making microcavities in a tungsten wire. The microcavity forming device includes a source of particles; a housing for receiving a heated tungsten wire; and a plurality of jet nozzles disposed in the housing for spraying the particles toward the heated tungsten wire. The particles are 0.35-0.75 micron in diameter. The heated tungsten wire is received in the housing and the jet nozzles spray the particles toward the tungsten wire to form the microcavities in the tungsten wire.

Abstract: A microchannel forming device is provided for making microchannels in a wire. The microchannel forming device includes a plurality of dice for receiving a heated wire spaced along a longitudinal axis. Each die has a circumferential surface forming an opening, and teeth projecting normally from the surface and terminating in the opening. As the heated wire is drawn through the opening of each die, the teeth engage the heated wire to form longitudinal microchannels therein.

Abstract: A microcavity forming device is provided that includes a microcavity forming means of making microcavities in a surface of a heated filament wire. The microcavity forming means includes an array of teeth for engaging the surface along a length dimension of the filament wire. The device further includes a drawing means of drawing the filament wire along the length dimension. The drawing means draws the filament wire along the length dimension and the array of teeth engages the surface of the filament wire to form the microcavities.

Abstract: A tuned optical resonator having a substrate and an input waveguide and an optical resonator waveguide formed on the substrate. The optical resonator waveguide has a resonant frequency, exhibits a first index of refraction, temporarily exhibits a second index of refraction responsive to application of laser energy, and temporarily resonates at the resonant frequency while the laser energy is being applied.

Abstract: A microchannel forming device is provided for making microchannels in a wire. The microchannel forming device includes a plurality of dice for receiving a heated wire spaced along a longitudinal axis. Each die has a circumferential surface forming an opening, and teeth projecting normally from the surface and terminating in the opening. As the heated wire is drawn through the opening of each die, the teeth engage the heated wire to form longitudinal microchannels therein.

Abstract: A wet type friction clutch and an electromagnetic clutch is disclosed wherein a pilot clutch 61 is disposed in a magnetic flux path 95 of an electromagnet 57 and is kept between an armature 71 and the electromagnet 57. Upon excitation of the electromagnet 57, the armature 57 is retracted to allow the pilot clutch 61 to be coupled. The pilot clutch 61 includes a plurality of clutch plates 87, 89 which are interleaved with respect to one another for sliding movements. Adjacent clutch plates 87, 87A, 87B, 89, 89A, 89B, 89C, 89D, 89E, 89F are formed with oil guide passageways 86, 96, 98, 106, 108, 110, 114 to create a hydrodynamic pressure effect to allow the clutch plates to be separated with a limited drag torque.

Abstract: A photonic crystal comprising a waveguide made of material. The waveguide has a periodic set of holes. The material proximate to at least one of the holes in the periodic set of holes exhibits an index of refraction that has been modified by the application of laser energy relative to the material proximate to other holes in the periodic set of holes. The photonic crystal is tuned to temporarily transmit a specific wavelength of light to create an on-off switch for the specific wavelength. Multiple photonic crystals are used to form a multiplexer and a demultiplexer.

Abstract: A photonic crystal comprising a waveguide made of material. The waveguide has a periodic set of holes. The material proximate to at least one of the holes in the periodic set of holes exhibits an index of refraction that has been modified by the application of laser energy relative to the material proximate to other holes in the periodic set of holes.

Abstract: A tuned optical resonator having a substrate and an input waveguide and an optical resonator waveguide formed on the substrate. The optical resonator waveguide has a resonant frequency, exhibits a first index of refraction, temporarily exhibits a second index of refraction responsive to application of laser energy, and temporarily resonates at the resonant frequency while the laser energy is being applied.

Abstract: The invention is an apparatus and a method for drilling holes in a work piece with a laser. A laser beam is received by the optical system and directed along an optical path. The system directs the laser beam through a moveable mask aperture creating a sub-beam, that is reduced in size by a lens system as it is imaged onto a work piece. Multiple features are formed in the work piece by moving the mask.

Abstract: A wet type friction clutch and an electromagnetic clutch is disclosed wherein a pilot clutch 61 is disposed in a magnetic flux path 95 of an electromagnet 57 and is kept between an armature 71 and the electromagnet 57. Upon excitation of the electromagnet 57, the armature 57 is retracted to allow the pilot clutch 61 to be coupled. The pilot clutch 61 includes a plurality of clutch plates 87, 89 which are interleaved with respect to one another for sliding movements. Adjacent clutch plates 87, 87A, 87B, 89, 89A, 89B, 89C, 89D, 89E, 89F are formed with oil guide passageways 86, 96, 98, 106, 108, 110, 114 to create a hydrodynamic pressure effect to allow the clutch plates to be separated with a limited drag torque.

Abstract: An apparatus for metal line deposition and a method for metal line deposition using the apparatus. A donor plate has a donor substrate transparent to a focused coherent light beam and a donor surface. The donor surface of the donor plate has a channel formed therein. The channel is coated with a metallic material. A deposition substrate onto which the metal line is to be deposited is disposed adjacent the donor surface of the donor plate. The focused coherent light beam is directed through the donor substrate of the donor plate and onto the metallic coating in the channel. The focused coherent light beam causes the metallic material to ablate from the channel by discharging ions of the metallic material away from the channel and onto the deposition substrate to form the metal line.

Abstract: A differential apparatus includes a differential casing, a pair of helical side gears and a pairs of helical pinion gears. The helical pinion gears are accommodated in bores formed in the differential casing, respectively. When it is expected that a helix angle of tooth trace of the helical pinion gear would be decreased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually decreased from axial ends of the helical pinion gear toward the axial intermediate potion. Conversely, when it is expected that a helix angle of tooth trace of the pinion gear would be increased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually increased from the axial ends of the helical pinion gear toward the axial intermediate potion.

Abstract: A flat cathode-ray tube in which a ceramics film or a glass film is formed by thermal spray on the coupled surface of a metal case. This assembly and a glass screen are coupled through crystallized frit glass or by glass fusion. The coupling between the metal case and the glass screen has a coupling strength sufficient to resist the vacuum stress. The metal case, which is not exposed for a long time to high temperatures during thermal spraying, can be made of a metal for realizing a lightweight without any thermal deformation or dimensional variations, thereby attaining satisfactory mechanical properties.

Abstract: A novel compound, a 2-chloropropionaldehyde trimer and a process of producing a 2-chloropropionaldehyde trimer by adding concentrated sulfuric acid to an organic solvent containing 2-chloropropionaldehyde and stirring the mixture at a temperature of from -5.degree. C. to 15.degree. C. to carry out the reaction.