Abstract: Apparatus is disclosed in a system for drilling holes with a laser beam in a plurality of discrete moving workpieces carried by a support which moves each workpiece sequentially along a predetermined path at a predetermined velocity, the apparatus including means for sequentially tracking along a portion of such path each workpiece being drilled seriatim by the laser beam. This tracing apparatus includes means for directing the laser beam generally transversely of the direction of movement of the workpiece on the support and a mirror for folding the transversely directed laser beam toward the workpieces with means for oscillating the folding mirror synchronously with the movement of the workpiece to track the workpiece as it moves.

Abstract: A pulsed power supply for a gas discharge laser in which a main DC power supply is connected in series with a current limited DC power supply and a gas discharge laser and with diode means connected across the second power supply for bypassing the second power supply and conducting current from the main power supply to the laser after the laser ionizes.

Abstract: A system for decoding encoded character information characterized by a plurality of bars of alternating light reflective characteristics of one or more widths in applications such as reader/scanner systems utilizing a decision tree technique that enables decoding to take place on line in real time.

Abstract: In order to prevent electrical discharges between the cathode electrode of a gas discharge laser and the closest metal resonator mirror, means are provided adjacent the optical path between the closest resonator mirror and the cathode electrode for conveying the electrical discharge from the cathode electrode to a reflectively inactive area of the mirror. In one preferred embodiment the electrically conducting means is a flanged tube coaxial with the optical path and having the flanged portion in electrical contact with the reflectively inactive area. In other embodiments the electrical conducting means include a metal block having a bore which is coaxial with the optical path; the block being in electrical contact with a reflectively inactive area of the mirror. In still another embodiment the electrical conducting means include a rod projecting from the mirror mounting block which is electrically connected to a reflectively inactive area of the mirror.

Abstract: A reader-scanner system using a laser as a source of a narrow beam of light and having optical means for directing the light beam from the laser to a scan target area with the optical means generating a pattern comprising a series of intersecting diagonal and horizontal lines relative to the path of objects which pass through the scan target area, with sequential scan pattern sets in the scan target area displaced in the direction of oncoming objects from the previous scan pattern set, with each of the lines defining each scan pattern set approaching the scan target area from a different direction and wherein the optical path of the incoming scan lines is shared by the reflected light as it travels to the system's optical detector.

Abstract: A discharge tube for a gaseous laser is terminated with windows made of crystalline quartz which do not fluoresce in the presence of high energy, visible and ultraviolet light radiation.

Abstract: One or more birefringent plates are placed within the optical cavity of an optical oscillator such as a dye laser. Each of the plates is positioned at an angle, such as Brewster's angle with respect to the light reflected within the optical cavity of the optical resonator. The output wavelength from the optical resonator is tuned, or its bandwidth narrowed, by rotating the birefringent plates while maintaining the plates at the same angle.