Abstract: A liquid crystal display assembly includes an untwisted nematic liquid crystal cell structure. The light transmittance of each pixel element of the assembly is a function of the pixel drive voltage. A phase compensating plate reduces the voltage necessary to permit switching, permitting compatibility with conventional thin film transistor (TFT) arrays but capable of greatly shortened response times. The configuration includes a combination linear polarizer and quarter wave plate which functions as a circular polarizer for blocking reflections from internal specularly reflecting surfaces within the liquid crystal display, thereby enhancing high ambient viewability.

Abstract: A disposable diagnostic pinwheel for use in testing for nerve dysfunction. The pinwheel can be applied to a handle which incorporates a pressure absorbing mechanism so that a more constant and controllable test can be conducted. The pinwheel can also include a removable cover which protects sharp points on the pinwheel from inadvertently injuring the user. In one embodiment the cover may also function as the grasping means during use of the pinwheel in testing procedures. In such a use the cover also includes the pressure absorbing mechanism.

Abstract: A scanning probe microscope is provided with a piezo-ceramic tube to carry the sensitive probe at its free end to translationally move the probe in the X and Y directions. Large stationary surfaces can then be scanned by probe tip motion. The tube is also capable of movement in the Z direction so that the tip can follow the contours of the surface. Optical detection means track the motion of the probe tip and generate signals corresponding to and representative of surface contours. In one mode of operation, the signals are used in a feed back loop to keep constant the spacing between the tip and the surface, in which case the error or control signals represent the contours.

Abstract: A combiner eyepiece with an enhancement imagery source and a collimating mirror is equipped with two oblique partially reflective mirrors. Both mirrors reflect some of the light impinging on their partially reflective sides and transmit substantially all of the rest of such light. The result is a collimated beam of light travelling toward the viewer along the viewing axis and expanded in vertical extent. This expanded vertical extent eases the requirement for the viewer to place his eyes in a precise location at the near end of the eyepiece. It also allows a smaller and lighter construction for an eyepiece where the vertical extent of the viewing area has been specified.

Abstract: An apparatus and method for increasing resolution and expanding the displayed field of view. The imagery is collimated and split into two paths by a partially reflective mirror set at an oblique angle to the image source. Either path may be blocked by a combination of polarizers and at least one controllable polarization shifting cell(s) (.pi.-cells). This mechanism allows one image source to supply, in alternating sequence, separate imagery to two separate but contiguous portions of a wide angle display. The two collimated image paths are merged about the viewing axis by a one way mirror before being recollimated at the device exit pupil.

Abstract: The efficiency of LC displays is improved by the use of a polymeric chiral nematic liquid crystal rear polarizer and reflective backlight housing which increases the net transmission of light and, at the same time, reduces the weight of the assemblage and increases battery life by utilizing lower levels of illumination. The polymeric chiral nematic liquid crystal can be a freestanding film or films, or can be supported by a single glass substrate. The liquid crystal polarizer can have a bandwidth sufficient to transmit electromagnetic radiation across the entire visible spectrum.

Abstract: A digital communications network for digital data comprising packets of a predetermined size. A transmitter and a receiver are connected to a set of buffers which are connected to a microprocessor which controls the data flow into and out of the buffers. The size of the buffers and hence the size of the data packets is relatively large. This allows the processor to perform per-packet operations in software which would otherwise be done in hardware, including routing decisions and error detection and correction. The network allows various topologies, is speed scalable, and simplifies resource allocation.

Abstract: A kit for replacing existing incandescent fixtures with a 2 D fluorescent fixture includes a plate with a ballast/transformer on the upper surface and a 2 D lamp socket on the lower surface. The ballast/transformer is coupled to the source of power through a separable connector which can be terminated either in an electrical plug which fits into an existing socket or, using conventional wire nut connectors, can be "hard wired" into place. Spring hangers, which can be attached to existing housing features, are loosely held to the upper surface of the plate so that in a first orientation, the plate is below the housing and access may be had to the housing interior and in a second orientation, the plate is held secure against the housing. A diffuser globe can be provided for installations which are not recessed.

Abstract: A backlight system for liquid crystal device display is equipped with a dual lighting system for day viewing and night viewing. The day lighting system uses conventional fluorescent or incandescent lamps for full color display during daytime use. The night lighting system uses a lower intensity light source. The day lighting system is disabled while the night system is in use. The dual lighting system provides an extended dimming range compared to what would otherwise be available.

Abstract: A process for assuring secure communication over a radio link and apparatus to perform the process includes a scrambler-descrambler installed at a multiple line input multiple line output telephone switch. Individuals equipped with compatible scrambler-descramblers can place calls to the switch and automatically transmit unique identity code information which, if recognized, opens an audio circuit and connects an available output telephone line. The individual can then place a telephone call to third party and all audio transmission over the radio link will be scrambled. Scrambled audio signals received at the switch are descrambled and passed to the third party. Audio signals received at the switch from the third party are scrambled and transmitted to the individual whose instrument descrambles the signal.

Abstract: A scanning probe microscope is provided with a piezo-ceramic tube to carry the sensitive probe at its free end to translationally move the probe in the X and Y directions. Large stationary surfaces can then be scanned by probe tip motion. The tube is also capable of movement in the Z direction so that the tip can follow the contours of the surface. Optical detection means track the motion of the probe tip and generate signals corresponding to and representative of surface contours. In one mode of operation, the signals are used in a feed back loop to keep constant the spacing between the tip and the surface, in which case the error or control signals represent the contours.

Abstract: A high speed media management device has tractor means for moving a web through the device past a plurality of work stations at each of which the web may be treated. Relatively high web tension is maintained throughout its travel path. Counting means near the beginning of the web path generate a count signal with the passage of each increment of web. The accumulated count signals are compared to numbers stored in a plurality of registers, each register associated with a work station and each containing a count representative of web travel distance relative to the work station. The first register count corresponds to the distance required to accelerate the web from a stop. The remaining registers store that count and a separate count representing the distance between the first station and the corresponding station. When the counter contents equals the count in a register, an actuating signal initiates a treatment activity at the associated work station.

Abstract: A demountable door securing device includes a door edge engaging plate with a right angled bend adapted to rest against one face of the door and an extended portion terminating in a hinge on the opposite side of the door. A rotating door engaging member including a planar portion and a right angled portion can be rotated to engage a face of the door. A security bar through apertured tabs in the extended portion prevents rotation of the planar portion. The right angled bend includes an extended bar portion parallel to the door face at the free end of which a hasp is pivotally mounted. The hasp rotates into engagement with the door frame and is held in place by a securing bar extending outward from the right angled bend. A tongue on the free end of the securing bar fits through an aperture in the hasp and holes in the tongue can receive a locking device.

Abstract: A high speed web cutter has a rotating roller with an extended bar mounted perpendicular to its surface and angled to be aligned askew with respect to the roller's axis. During the rotation of the roller, the bar interferingly contacts a plate having an angled edge that is mounted on a relatively stiff cantilever spring. The bar edge and the plate edge are not mounted parallel with each other nor are either of them parallel with the plane of the web. As the roller rotates, the extended bar deflects the cantilever spring, allowing the edges to intersect in a cutting intersection that travels axially with roller rotation, thereby severing a web member passing between the roller and the plate edge.

Abstract: A scanning force microscope is provided with apparatus to modify the light source with a modulation scheme. Information relative to scanning tip motion is included in a modulated light beam which is then demodulated and filtered to recover the information in the form of a signal which corresponds to and is representative of a chosen parameter of tip motion.

Abstract: A tease-proof rotary switch has a driving shaft which is coupled to a driven shaft through a coupling spring. The driven shaft is connected to a rotating switch assembly. The driving shaft rotates, storing energy in the spring which, in turn, can rotate the driven shaft. The energy stored in the spring may be sufficient to start the rotation of the switch and to seat it in the next stable switch position. Alternatively, the driving shaft can engage an element of the driven shaft to start the rotation which can then be completed to the next stable position by the energy stored in the spring.

Abstract: A housing for mounting electrical fixtures behind surfaces such as walls and ceilings, includes a surface flange and a plurality of pairs of axially directed slots in the side wall. When inserted in a hole in a ceiling or wall until the housing flange is flush with the wall or ceiling surface, a pair of spring elements are compressed and inserted through a pair of slots which allow the springs to bear against the slot and interior surface of the ceiling or wall to hold the flange flush.