Abstract: An electrophoresis instrument includes a capillary tube mounted in an air cooled cartridge. The cartridge also supports a spherical lens which is part of the optical detection apparatus. The cartridge rests in a manifold which includes the sample and buffer reservoirs. The temperature of the capillary tube is controlled by measuring the electrical resistance of the capillary tube during the electrophoresis process and then cooling or heating the cartridge by circulating temperature controlled air over the tube. The optical path associated with the instrument is a fiber optic bundle bifurcated close to dual detectors into a reference arm and a sample arm so as to provide similar reference and sample optical paths. The instrument may be used for temperature control for gradient electrophoresis and also, a neutral marker for determining electro-osmotic flow may be automatically detected.

Abstract: A heater/mixer device is disclosed for use with laboratory vials, test tubes, or similar containers containing liquids. The heater/mixer includes a chamber formed in a block of material such as aluminum, with an electric heating element in contact with the block. The vial fits loosely in the chamber. Compressed air passes into the chamber through an inlet in the block, so that the vial is revolved by a circular air flow in a vortex fashion. This revolving motion creates a vortex in the liquid inside the vial, and so mixes the liquid. The air circulation also improves heat transfer from the block to the vial.

Abstract: A window seal for a bar code laser scanner comprising a silicone foam gasket to form a flexible, soft, durable, compressible and hydrophobic seal between the bar code laser scanner chassis window and the top window on a bar code laser scanner.

Abstract: A Z-fold paper elongated guide having a width approximately the with of Z-fold computer paper is positioned at the exit of a platen/printer carriage interface in a keyboard-operated computer printer or integrator. The guide not only guides printed-on paper sheets to a printed-on paper storage bin or surface but allows Z-fold paper sheets to be hand directed forwardly toward the computer keyboard for floor storage of the paper in front of the printer. A pair of hump-like rails extend on the top surface of the guide to open up the angle of repose between adjacent Z-fold sheets when the sheets are being reversed in driven direction so as to be transported back through the platen/printer carriage interface. The rails are sloped upwardly in a rearward direction at about 13.degree. and extend to a position juxtaposed to but not touching a transverse rear tear edge of the guide.

Abstract: An electrophoresis instrument includes a capillary tube mounted in an air cooled cartridge. The cartridge also supports a spherical lens which is part of the optical detection apparatus. The cartridge rests in a manifold which includes the sample and buffer reservoirs. The temperature of the capillary tube is controlled by measuring the electrical resistance of the capillary tube during the electrophoresis process and then cooling or heating the cartridge by circulating temperature controlled air over the tube. The optical path associated with the instrument is a fiber optic bundle bifurcated close to dual detectors into a reference arm and a sample arm so as to provide similar reference and sample optical paths. The instrument may be used for temperature control for gradient electrophoresis and also, a neutral marker for determining electro-osmotic flow may be detected.

Abstract: A portion of first reference light plane is intercepted by a first one of a pair of angularly oriented reflective surfaces and reflected by the second of the pair of reflective surfaces as a second reference light plane at a selectable angle relative to the first reference light plane. The first and second reflective surfaces are movably mounted such that the first reflective surface can be rotated about a first axis coincident with or parallel to an incidence line in the first reflective surface which receives the first light plane and the second reflective surface can be rotated about a second axis parallel to but spaced from the first axis. The first and second reflective surfaces are mounted such that when the first reflective surface moves through an angle of a/2 degrees, the second reflective surface moves through an angle of a degrees.

Abstract: A pendulous compensator for use in a light beam projector including a light beam source comprises first and second upper pulleys spaced from one another and secured to the light beam projector. First and second lower pulleys are positioned beneath the first and second upper pulleys and supported by filament strands, tapes, loops or the like extending around the upper and lower pulleys. A pendulum mirror is secured to and supported between the first and second lower pulleys for receiving a light beam from the light beam source and reflecting the light beam in a desired angular orientation relative to horizontal. The first and second lower pulleys in the pendulum mirror are supported such that the pendulum mirror is moved to compensate for tilting of the light beam projector. The first and second upper pulleys or a folding mirror may be controlled to select a grade angle relative to horizontal of a projected light beam.

Abstract: A method and system for stabilizing the output frequencies of a multimode laser of the type which operates in at least three optical cavity modes includes detecting the intermodulation product frequency, using a suitable photodetector. The optical cavity modes may be either purely longitudinal for a single transverse mode, or may include radiation from multiple transverse cavity excitations, also with possible longitudinal plurality. The detector output is monitored for the intermodulation product beat signal which is contained in the detector current at the differences of the primary difference frequencies of the optical modes. A signal derived from the frequency of the intermodulation product term is compared with a reference signal, and the resulting error signal is driven to zero by varying the optical length of the laser oscillator cavity in response to the error signal, thereby causing the operating modes of the laser to be stabilized.

Abstract: Motion damping apparatus is provided for use in a light beam projector including a light beam and a pendulous compensator adapted to movably support a mirror for deflecting the light beam to compensate for tilting of the projector. The apparatus comprises at least one motion damping plate formed of an electrically conducting material and coupled to the pendulous compensator. Magnets are positioned adjacent the damping plate for generating a magnetic field through which the plate passes as the result of motion of the pendulous compensator such that the motion is damped by the interaction of magnetic fields produced by the magnets and by eddy currents generated in the plate by its movement within a magnetic field. The motion damping plate preferably is curvilinear and coupled to the pendulous compensator to move in substantial conformity with a corresponding curvilinear plane defined by the movement of the pendulous compensator.

Abstract: There is disclosed herein several gas resupply valves for replenishment of lost gas in gas lasers in general and argon ion lasers in particular. The first embodiment uses a valve which controls flow of gas into a metering volume. The metering volume has an aperture therein which is microscopically small and which has a diffusion constant for gas moving through the aperture which is less than the time the valve is held open. The second embodiment uses the same general structure, but separates the soft sealing member of the valve from the solenoid core which moves to open and close the valve. The soft sealing member is attached to the valve body and supported above a valve seat surrounding the opening of the metering volume. The third embodiment uses a thin diaphragm which overlies a flat surface of the valve body in which are formed an input port and an output port. A solenoid applies pressure against the diaphragm to cause it to flatten against the flat surface thereby sealing the valve.

Abstract: An electrophoresis instrument includes a capillary tube mounted in an air cooled cartridge. The cartridge also supports a spherical lens which is part of the optical detection apparatus. The cartridge rests in a manifold which includes the sample and buffer reservoirs. The temperature of the capillary tube is controlled by measuring the electrical resistance of the capillary tube during the electrophoresis process and then cooling or heating the cartridge by circulating temperature controlled air over the tube. The optical path associated with the instrument is a fiber optic bundle bifurcated close to dual detectors into a reference arm and a sample arm so as to provide similar reference and sample optical paths. The instrument may be used for controlling temperature in gradient electrophoresis and detecting neutral markers in determining electro-osmotic flow.

Abstract: A switched cavity laser system which includes a resonant cavity, a gain medium within the resonant cavity, a cavity switch and an output coupler. A controllable pump energy source delivers pump energy to the gain medium in response to an energy control signal. A detector is coupled with the gain medium and generates a detector signal in response to the amount of population inversion exhibited by the gain medium. A control circuit is coupled to the detector and controllable pump energy source for generating the energy control signal in response to the detector signal. As the switching rate of the Q-switch is varied, the energy control signal varies to ensure a constant level of population inversion between each pulse. In this matter, a prespecified pulse energy is achieved for each pulse independent of the switching rate of the Q-switch.

Abstract: A conventional injection valve, such as used in high performance liquid chromatography apparatus, having six ports and three channels for connecting the ports in two different positions, is modified so that one of the channels is longer than the other two. In this way, when the valve is switched to the load position, one of the ports is always connected to the channel prior to the other port being connected. This improvement in the valve makes the valve more accurate and reduces undesirable mixing of sample and mobile phase in the valve when injecting small quantities of sample.

Abstract: A method and apparatus for sweeping a laser beam in a laser scanner is disclosed wherein a laser beam traveling along a path from a laser beam source is directed upon a scanner mirror which reflects the beam into scan pattern mirrors to project a scanning pattern for each sweep of the laser beam. A rotary actuator supports and rotates the scanner mirror to sweep the laser beam onto the scan pattern mirrors and a linear actuator in turn supports and linearly moves the rotary actuator and scanner mirror generally along the path of the laser beam to vary the point of focus of the laser beam and thereby expand the effective depth of field of the laser scanner.

Abstract: A data gathering system for use in a checkout counter to determine information relating to products to be purchased and to provide such information to a cash register system includes a scale supported within the checkout counter for determining weights of products presented to the data gathering system. The scale includes a subplatter located below the upper surface of the checkout counter. An optical scanning arrangement is supported on the subplatter for reading coded labels on the products. A common interface circuit is responsive to both the scale and the optical scanning arrangement, for providing weight data and coded label data to the cash register system.

Abstract: A method and apparatus is disclosed for installing a data gathering system in a checkout counter such that it extends slightly above the surface of the counter. The data gathering system defines an entry side and an exit side. Products to be processed by the system are passed from the counter to the system over the entry side of the system, processed and then passed from the system to the counter over the exit side of the system. The counter adjacent the entry side of the system is elevated such that products processed by the system pass along a downwardly stepped path from the elevated portion of the counter down to the system and then from the system down to the counter on the other side of the system. Preferably, counter elevation is performed by a tapered trim strip which is secured across the counter adjacent the entry side of the data processing system.

Abstract: A soft compliant seal is attached to either an anchored or a loose reinforcement ring to provide a non-hermetic seal against liquids or particulates in order to maintain a space between two windows substantially free of all foreign matter.