Abstract: An endbell assembly operatively associated with a laser body includes a metal endbell component sealed to a crystalline endbell component which terminates with a crystalline optical component. The crystalline endbell and crystalline optical component are hermetically sealed without using a frit. This is achieved by polishing and a modified optical contacting technique whereby the optical component and crystalline endbell component are polished to a flatness of about 1/2 wavelength of light, placed in a contacting position and then thermally cycled at a temperature of about 400.degree.-500.degree. C. for about 1 to 10 hours, forming a substantially uniform unitary body. This seal is mechanically strong and minimizes the introduction of contaminants into the endbell assembly. In one embodiment, the crystalline endbell component is metallized and braze-sealed to the metal endbell component. In another embodiment, the two endbell components are hermetically sealed by modified optical contact and thermal cycling.

Abstract: A neodymium or other rare earth doped solid state laser is pumped by a matched high efficiency laser diode, resulting in a compact, high efficiency and long lifetime laser assembly. Output is in the near infrared range, but can be converted to the visible spectrum by an intra-cavity frequency doubler. A doubling crystal, which may be a KTP crystal, is placed at an optimum location in the laser cavity. Polarization of the beam may be achieved simply by stressing a non-birefringent rod, prior to frequency doubling, or by using a birefringent material such as Nd:YLF for the rod. An amplitude noise suppression elaton may also be placed at an optimum position in the laser cavity; alternatively a ring cavity or pair of quarter wave plates can be used. A folded cavity configuration produces a pair of beam waists in the cavity. Pulsed operation can be produced by means of a Q-switch.

Abstract: An optical scanner apparatus particularly suited for use in a laser bar code reader includes a series of mirrors mounted in a basket-like array about the optical beam axis. A mirror is mounted obliquely across the beam axis, directly on the path of the beam, to fold the beam generally radially outwardly toward the array of mirrors. In one embodiment of the invention the oblique first mirror is rotated about the beam axis, while in another embodiment the oblique first mirror is held stationary and the array of mirrors is rotated, to reflect the beam forwardly, generally in the direction the beam axis is pointing. If the oblique first mirror rotates, a plurality of scan lines, including non-parallel scan lines, are formed on a surface to be scanned; if the array of mirrors is rotated instead of the single mirror, a series of parallel scan lines will be produced. The mirrors can be oriented at desired angles to produce virtually any desired scan pattern.

Abstract: A beam delivery system for delivering a laser beam from a stationary laser to a point in space under robot control has a universal or spherical shoulder joint which is free to rotate in any direction, a wrist joint which receives the beam from the shoulder joint and which allows the beam to be pointed in the required direction and a section of sliding tubes which couple the wrist joint directly to the shoulder joint in a straight line. The beam delivery system is constructed to be readily and effectively associated with a robot. The beam delivery system is mounted with the spherical or universal shoulder joint close to the vertical axis of the robot shoulder and with the spherical shoulder joint below the articulated arm mechanism of the robot so that the beam delivery system accesses a maximum volume beneath the articulated mechanism of the robot. The beam delivery system utilizes a minimum of internal mirrors to minimize power loss in the beam.

Abstract: A hand held bar code reader employs a laser diode as its laser source, for an efficient and compact construction. The diode is modulated, and an associated bar code reading detector is timed accordingly, so that (1) the effects of strong ambient light which may be present on the bar code surface can be subtracted out, by alternating reflected light readings of the detector between laser beam plus ambient and ambient alone, and subtracting the readings electronically, and (2) peak power can be increased to obtain more dependable readings while staying within permissible power levels for such devices, since average power is reduced by the modulation of the laser.

Abstract: A method for checking straightness of an elongated generally cylindrical bore, such as a capillary bore, includes directing a collimated light beam through the bore, with the bore skewed slightly with respect to the beam. This causes a wall of the bore to reflect some of the beam light, forming generally an off-axis ring of reflected light beyond the end of the bore, in addition to an on-axis spot of un-reflected light. Variation in the off-axis reflected light ring pattern by scatter of reflected light indicates non-straightness of the reflecting bore wall. Variation of the light in the ring is determined by measuring equipment. The cylindrical bore may be rotated sequentially through a plurality of positions, such as four positions, to check the entire circumference of the bore. The degree of bore non-straightness may be quantitatively measured electronically or mechanically.

Abstract: A temperature responsive, gas entrapping material contained in a chamber connected to a gas laser tube selectively entraps gas to regulate the pressure in the laser tube. A temperature regulator adjusts the temperature of the gas entrapping material and thereby controls the pressure of the gas in the laser tube. The temperature of the gas entrapping material can be adjusted by cooling or by heating. The pressure in the laser tube is monitored. The tube voltage can be used to monitor the pressure. Temperature adjustment of the gas entrapping material permits development of optimum gas pressure in the laser tube for different wave lengths. In one embodiment the laser is a krypton gas laser and the gas entrapping material is activated charcoal or alumino-silicate. The gas entrapping material may be heated, during assembly of the gas laser, to a temperature high enough to remove foreign material which might otherwise interfere with the operation of the laser tube.

Abstract: An optical component of a laser of the type including a hot gas plasma region, a cold gas region and producing large photon fluxed includes an optical element and a coating means on a surface of the optical element exposed to the photon fluxes. The coating means is comprised of a material adapted to minimize photoreduction of the optical element induced by exposure to the photon fluxes. Optical elements of the present invention include windows, birefringent plates, intra-cavity lenses, polarizers and mirrors.

Abstract: A plasma tube for a gas laser includes a series of heat webs and insulative spacers between the heat webs, with tungsten bore insert members supported by the heat webs and having aligned apertures defining a laser discharge path. To produce the plasma tube, the heat webs, spacers and other connected components are assembled in a vertical stack outside the ceramic tube of the laser, with a stacking gauge which helps assure that the heat webs are correctly spaced apart within close tolerances. The heat webs lie adjacent to annular metallized areas on the inside surface of the ceramic tube when the assembly is inserted into the tube, which is precision-formed ceramic tubing. The tube assembly is heated in vertical orientation to expand the heat webs diametrically so that they engage outwardly against and are brazed to the metallized areas of the ceramic tube.

Abstract: A magnetic speed device includes a rotatable driving shaft and a driven shaft also rotatable about an axis. A stationary pole includes a plurality of pole elements, each having at least one stationary pole surface. The pole elements are circumferentially arranged around the axis. A rotor is operatively coupled to the driven shaft for rotation with the driven shaft about the axis. The rotor includes a plurality of circumferentially arranged rotor pole surfaces. The number of rotor pole surfaces is different from the number of stationary pole surfaces. The rotor pole surfaces are disposed in a spaced, generally opposed relation to the stationary pole surfaces, and define a series of air gaps therebeween. A magnet is mounted for rotation with the driving shaft for supplying a magnetic flux to a flux path which includes successive, adjacent pairs of pole elements, the rotor, and the air gaps.

Abstract: A dispersion compensation delay line is added to a synchronously pumped fiber Raman ring oscillator to generate subpicosecond pulses. A pair of spaced gratings form the delay line. An interference filter is used as a bandwidth limiting tuning element to provide a good quality short pulse. An integrated design eliminates the discrete optical elements by using only an optical fiber and an optical fiber coupler.

Abstract: A method and system for stabilizing the phase relationship of two RF-controlled mode locked lasers involves monitoring the output of both lasers and, with a phase detector/comparator, generating a voltage proportional to the phase difference between the two lasers. The voltage is amplified and filtered and fed into a voltage controlled phase delay connected to the mode locker of one of the lasers. The phase delay operates to delay the RF signal to the one laser according to the desired phase relationship. By disclosed methods and apparatus a single laser can also be stabilized to its own RF drive source to reduce noise effects, two lasers can be individually stabilized to a single RF source, or two lasers can each be stabilized to their own separate RF sources.

Abstract: A plasma tube for a gas laser includes a series of heat webs and insulative spacers between the heat webs, with tungsten bore insert members supported by the heat webs and having aligned apertures defining a laser discharge path. To produce the plasma tube, the heat webs, spacers and other connected components are assembled in a vertical stack outside the ceramic tube of the laser, with a stacking gauge which helps assure that the heat webs are correctly spaced apart within close tolerances. The heat webs lie adjacent to annular metallized areas on the inside surface of the ceramic tube when the assembly is inserted into the tube, which is precision-formed ceramic tubing. The tube assembly is heated in vertical orientation to expand the heat webs diametrically so that they engage outwardly against and are brazed to the metallized areas of the ceramic tube.

Abstract: A transmitter for an alignment system in which a field of electromagnetic radiation is propagated in a non-planar reference cone is disclosed. The transmitter includes a source for providing a collimated beam of electromagnetic radiation directed parallel to a beam axis. A cantilever strand supports a bob within the beam. The bob has a conical reflecting surface to reflect the collimated beam conically. Optimally, the cantilever strand and bob are chosen to provide a deflection between the bob and plumb which is substantially one-half of any angular error between the beam axis and plumb. In an especially preferred form, a housing surrounds the bob and has inner and outer surfaces which minimize temperature effects on the orientation of the reference plane. Also, detectors are provided to sense when the angular error between the beam axis and plumb is outside of an acceptable range.

Abstract: A laser instrument of the kind used to read or to detect light reflected from a target which is spaced from the laser instrument comprises a laser for generating a laser beam for transmission to the target, and a detector for detecting light reflected from the target and a trifocal, composite, single piece lens system. The trifocal lens system receives the laser beam from the laser at an angle which is off the optical axis of the lens system, routes the received laser beam onto the optical axis for transmission through the lens system and toward the target, collects light reflected from the target and images and transmits the collected light along the optical axis to the detector means. In a specific embodiment of the invention the trifocal, composite, single piece lens system is a plastic molded structure.

Abstract: A detector device for a rotating light beam, which beam defines a reference plane, includes a pair of adjacent detector elements which provide detection signals when illuminated by the beam. If the beam is above or below a first reference band, the detection signals differ sufficiently in amplitude to actuate a comparator. An averaging circuit determines if the beam is above or below the first reference band during a certain number of a set of immediately preceding rotations of the beam, and appropriate visual and audible indication are produced. The device may also provide an indication that the beam is above or below a second reference band which is aligned with, but wider than, the first reference band. The widths of the reference bands may be adjusted.

Abstract: A window assembly for a laser uses a uniaxial crystalline material such as quartz for the window, secured directly in a hard seal to a metal tubular end component. In order to avoid significant differential thermal expansion between the quartz window and the end component, the quartz crystal is cut in a Z-normal configuration, whereby the thermal expansion and other physical properties of the window are isotropic in the plane of the window. The ability to make a reliable direct seal to a metal component offsets any disadvantages of the Z-normal configuration thought to be controlling in the prior art. Through the disclosed method for assembling and mounting the window, reflection loses are reduced to a practical minimum comparable to that of any preferred conventional window orientation.

Abstract: Apparatus for projecting a laser beam to provide simultaneously a stationary reference beam and a moving reference beam, which rotates in a plane normal to the stationary reference beam, includes a beam diverting arrangement for intercepting a primary beam and for splitting the beam into the two reference beams. The beam diverting arrangement includes first and second deflecting elements which deflect the beam by 90.degree. with respect to the primary beam. A portion of the primary beam, striking the first deflecting element, passes through the element and is shifted slightly by refraction. This shift is compensated by a third beam deflecting element which is fully transmissive, and which refracts the stationary reference beam into alignment with the primary beam. By cutting the first and third deflection elements from the same sheet of material and reorienting the elements appropriately, slight deviation from parallelism in the opposing surfaces of the sheet of material are compensated.

Abstract: A laser alignment system includes a transmitter and one or more receivers. The transmitter produces an alignment field by projecting laser energy in a non-planar reference cone, and the receivers locate this reference cone with photodetectors. The laser energy in the alignment field is modulated at 8 kHz and the signals produced by the photodetectors are filtered and amplified to increase the range of the system. Each receiver operates a display which indicates when it is aligned in the reference cone, and it produces an out-of-level indication when the transmitter is not properly aligned.

Abstract: A sealed rotary compressor is provided which includes separate pump and gear chambers. Disposed within the pump chamber is a set of rotors operatively associated with a set of gears rotatably mounted within the gear chamber. A substantially pressure differential exists between the two chambers. Rotational power is applied directly to the rotors through a static seal rather than through the gears which are utilized primarily to transmit the dynamic load. The pump chamber is defined by two end plates with a surrounding thin-walled housing. Within the pump chamber are interior thin wall members with the rotary members disposed therebetween and defining inlet and outlet pockets operatively associated with a pump housing inlet and outlet means.