Abstract: An automatic plumb, level, pointing and distance measuring tool uses a visible laser diode to project a beam in any of several different modes through a beam exit window. The tool, approximately the size and shape of a tape measure, can be placed on one edge to project a tilt-compensated vertical beam. Placed on another edge 90.degree.-rotated, the tool projects through the same exit window a tilt-compensated horizontal beam. When laid on either of its larger flat sides, the tilt compensation becomes inoperative and the tool projects a beam which is fixed relative to the housing. Acoustic distance measurement is facilitated using a second component or target side device which is activated to send an acoustic signal across a space to be measured, toward the laser tool. A receiver in the laser tool detects arrival of the acoustic signal and causes the laser to project a characteristically modulated or pulsed beam, received at a photodetector on the target side device.

Abstract: A laser scanner and method for simultaneously generating both a pointer beam and a scan pattern from a single laser source is provided by multiplexing a laser beam between at least one pointer beam path and at least one scanning beam path. Means for multiplexing include refractive and reflective optical components, and electronic means for modifying one or more properties of the laser beam.

Abstract: A point of sale (POS) bar code scanner such as in common use in retail stores includes provision for reading bar coded redemption coupons (or other bar coded documents redeemable for value) in a manner secure from a human operator. Integration of functions between the POS scanner and the coupon reader varies with different embodiments described. Through software associated with bar code decoding logic, a comparison is made between information on a validation coupon and information on items presented for purchase, and a decision is made as to whether the redemption coupon is valid and redeemable in this transaction. In one embodiment, the bar code scanner simply receives the redemption coupon face down on the product scanner window, and integrated decode logic of the scanner identifies the bar code as belonging to a redemption coupon, then makes the comparison and validation of the coupon for the particular transaction.

Abstract: An automatic plumb, level and pointing tool uses a visible laser diode to project a beam in any of three different modes through a beam exit window. The tool, approximately the size and shape of a tape measure, can be placed on one edge to project a tilt-compensated vertical beam. Placed on another edge 90.degree.-rotated, the tool projects through the same exit window a tilt-compensated horizontal beam. When laid on either of its larger flat sides, the tilt compensation becomes inoperative and the tool projects a beam which is fixed relative to the housing. In a preferred embodiment, separate pendulous or cantilevered mirrors are used for vertical and horizontal tilt correction and are selected by the influence of gravity as the tool is laid on one edge or the other. In further described embodiments, two separate laser diodes may be used, or the laser tool may be intergrated with other tools such as a tape measure or a squaring tool.

Abstract: A gas valve which is particularly useful in a laser gas fill system requiring repeated fillings includes a conduit positioned between high and low pressure gas regions. Within the conduit is a restriction, and this restriction is closed by a meltable solid material. When the valve is to be opened, heat is applied to the meltable solid material, either internally or externally, causing at least some of the material to flow and allow the passage of gas from the higher pressure region to the lower pressure region. When the pressure between the two regions has substantially equalized, or at least the pressure differential has greatly diminished, surface tension associated with the restriction in the conduit pulls the liquified material back into place to close and reseal the valve, at which point heat application is dicontinued so that the material again becomes solid.

Abstract: A bar code scanner which preferably generates an asterisk-like scan pattern has a scanner head at the end of a flexible mount enabling operator personnel to orient the scanner head in virtually any position and direction. The scan pattern generator is compact in size, utilizing a laser diode as a source, so that the scan head is easily manipulated to the desired position. In preferred embodiments the scanning mechanism generates the asterisk scan pattern with a rotating mirror or mirrors and a series of peripheral mirrors or lenses, one for each scan line, in an efficient and compact arrangement. The entire asterisk scan pattern may be constantly rotated at a relatively slow rate, so that bar code labels are more likely to be read without deliberate orientation by the operator, particularly in the case of bar codes of high aspect ratio.

Abstract: A point of sale bar code scanner, such as a grocery store check-out label scanner, that is attendant-free and completely automated in providing a listing or a total pricing of a customer's selected items. At each automated check-out, the customer initiates the process, places items on a conveyor, which carries each item separately through a scanner. The scanner reads all sides of each package, including the bottom of the package, since the bar code label could be located on any surface. Serial conveyors are used, and gates preferably control the advancement of items onto a conveyor which will carry the item through the scanning area, such that only one item can be scanned at a time. The conveyor in the scanning area includes a series of belt strips through which an upwardly scanned beam can read the package bottom. Various methods and systems are disclosed for handling "no reads". The customer signifies termination of the process at the appropriate time.

Abstract: Glass laboratory vials are marked by grinding the surface of the vial with an abrasive wheel. The vial is moved relative to the wheel under control of a computer so as to automatically grind a desired bar code or alpha-numeric symbols into the surface. The ground portion of the surface of the vial scatters light while the unground portion of the surface transmits light.The process is automated and can be performed by a robot as part of an analyzing or processing system. The ground-in markings are more enduring than the prior art paper labels.

Abstract: Three dimensional objects or models, such as three dimensional images or shapes stored in a computer, are generated as real models by addition of material to a base, such as with photo-hardenable liquid, or by removal of material from an initially oversized mass. Optical feedback is employed to monotor the actual condition of the model being formed, at each work site. The condition of the model at the work site, e.g. the presence or absence of material, is fed back to the machine or building tool, or to a computer controlling the tool. On the basis of such monitoring and feedback, decisions are made whether or not to perform more work at any particular work site. In this way, the actual three dimensional model being constructed is made to conform substantially to stored information relative to the desired dimensions of the model. In a preferred embodiment, models are produced by ablating a mass of small spheres held together by a relatively weak wax or cement.

Abstract: A tool for use in establishing a precise level line or plumb line or line for alignment uses a visible laser diode for projecting the line. The tool is relatively small and compact, drives the laser diode using batteries contained in the tool, and includes tilt compensation for use on surfaces which are not level, up to about 5.degree. off level, for still delivering a truly plumb or truly horizontal beam. A manual selector device is provided for shifting the beam from a vertical orientation to a horizontal orientation when desired. Specific forms of tilt compensation apparatus are disclosed.

Abstract: A laser beam three dimensional position measurement system includes a laser transmitter mounted at a stationary reference position at a work site and a receiver mounted on a mobile machine at the site. The transmitter produces a laser reference plane by sweeping a laser beam about the transmitter. The receiver includes a retroreflector which intercepts and reflects laser energy back to the transmitter when the laser beam sweeps past the retroreflector. The system also includes at the transmitter a circuit composed of a photodetector, timer, clock and counter. The photodetector senses laser energy reflected back to the transmitter from the retroreflector. The timer modulates the laser beam produced by the transmitter in response to detection of the beam. The counter is connected to the clock and timer, and is enabled by the timer to start counting electrical pulses received from the clock when the beam is modulated. The counter is disabled to stop counting electrical pulses when the modulation is detected.

Abstract: A fast axial flow laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retoreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.

Abstract: An ion laser includes a plurality of thin refractory metal disk members with the perimeter of the disks embedded directly into a ceramic plasma tube. A central aperture is formed in the middle of each disk, and a plurality of apertures are formed around the periphery of the disk. In the fabrication process, ceramic powder is compacted to form an outer plasma tube. Two separate tubes, each with electrodes and embedded washer ends, can be formed and fused to form a single tube. The disks (with the surrounding compacted ceramic disposed around the periphery of the disk) are stacked within the plasma tube and the green ensemble of ceramic and metal is fired in only one furnace step with controlled atmospheres. Hermetic cathode and anode electrodes are also formed in the same firing through the plasma tube. Ends are sealed with a mirror-mount of the Brewster window structure, in one embodiment either laser welded or soldered to a refractory metal end disk embedded in the green ceramic at the ends of the tube.

Abstract: A tool for use in establishing a precise level line or plumb line or line for alignment uses a visible laser diode for projecting the line. The tool is relatively small and compact, drives the laser diode using batteries contained in the tool, and includes tilt compensation for use on surfaces which are not level, up to about 5.degree. off level, for still delivering a truly plumb or truly horizontal beam. A manual selector device is provided for shifting the beam from a vertical orientation to a horizontal orientation when desired. Specific forms of tilt compensation apparatus are disclosed.

Abstract: A flowing gas laser, of the kind in which gas flows continuously through the lasing region and is circulated through the heat exchanger for cooling before being returned to the lasing region, comprises a resonator module and a blower module. The optical components of the laser are mounted on an outer surface of the resonator module, and the resonator module has an interior structure for conducting the circulating gas to the lasing region. The blower module has heat exchange structure for cooling the circulating gas and has a blower for pumping the circulating gas. The blower module is physically separated from the resonator module to prevent the heat and vibration of the blower module from distorting or otherwise affecting the structure or the performance of the optical components. Ducting the interconnects the resonator module and the blower module for circulating the gas between these modules.

Abstract: An ion laser includes a plurality of thin refractory metal disk members with the perimeter of the disks embedded directly into a ceramic plasma tube. A central aperture is formed in the middle of each disk, and a plurality of apertures are formed around the periphery of the disk. In the fabrication process, ceramic powder is compacted to form an outer plasma tube. Two separate tubes, each with electrodes and embedded washer ends, can be formed and fused to form a single tube. The disks (with the surrounding compacted ceramic disposed around the periphery of the disk) are stacked within the plasma tube and the green ensemble of ceramic and metal is fired in only one furnace step with controlled atmosphere. Hermetic cathode and anode electrodes are also formed in the same firing through the plasma tube. Ends are sealed with a mirror-mount of the Brewster window structure, in one embodiment either laser welded or soldered to a refractory metal end disk embedded in the green ceramic at the ends of the tube.

Abstract: A multiple pane lighthouse assembly in a reference laser beam projecting apparatus includes a plurality of transparent panes disposed in an arrangement that defines a transparent window structure which permits transmission of laser light therethrough and has a generally polygonal cross-sectional shape. The window structure has spaced corners formed by pairs of adjacent ones of the opposite side edge portions of the panes. The side edge portions of the panes in each pair are offset relative to one another in forming a respective corner. The offset position of the side edge portions of each pair in forming a respective corner exposes only an interior edge on one of the adjacent side edge portions to laser light being transmitted through the window structure. The path of laser light through the adjacent side edge portions forming the corner is thereby affected only by one interior edge on the respective one of the adjacent side edge portions of the panels at each corner.

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 chassis with a source fixed to the chassis for providing a beam of electromagnetic radiation and an optical deflector which converges toward the source reflects the beam into an omni-directional cone of radiation. A flexible support having an omni-directional stiffness supports the optical deflector in the beam to reflect the reference field in a level orientation when the chassis is level. An angular error in the orientation of the chassis from level results in the optical deflector deviating from the aligned position to maintain the reference field in the level orientation. Damping of the deflector is also provided for and sensors detect when the angular error of the chassis has exceeded an allowable amount.

Abstract: A fast axial flow folded laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retroreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.

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.