Abstract: A dumping apparatus for roll-out cart waste receptacles employs a tipper plate which includes a lifting mechanism and a lock plate which includes a locking mechanism. The tipper and lock plates are mounted for pivotal movement about respective first and second pivot axes on a mounting support that is attachable to a waste collection vehicle. A hydraulic cylinder has a trunnion mounting to the mounting support and an extensible rod member that is pivotally attached at one end to the tipper plate. The hydraulic cylinder functions as a drive mechanism for moving the tipper plate about the first pivot axis. The pivotal movement of the tipper plate causes the lifting mechanism to engage the pick-up bar and thereby lift the receptacle to bring its lock bar into engagement with the locking mechanism of the lock plate. The lock plate at all times moves about the second pivot axis in cooperation with and in the same rotational sense as the driven pivotal movement of the tipper plate.

Abstract: A head up display includes a simplified holographic combiner which has a low surface spatial frequency for avoiding flare. Symbology generated by a cathode-ray-tube is focused by relay optics and then reflected by a holographic optical element toward the holographic combiner. The last mentioned holographic optical element is provided with optical power in part compensating for distortions attributable to the large off-axis angle at which the holographic combiner is operated.

Abstract: A translatable and rotatable mechanism is employed in optical processing apparatus for exposing a specimen pattern and inspecting light pattern or image developed from it. The mounting mechanism includes a plate that is rotatably mounted on a linear positioning table assembly. The plate includes a substrate arm and a camera arm that extend in opposite directions from the axis of rotation of the plate. The specimen pattern, such as a photomask, is positioned on the free end of the substrate arm, and a video camera is positioned on the free end of the camera arm. Whenever the plate is rotated to an exposure orientation, the photomask diffracts light rays emanating from a laser. The diffracted light rays interfere with a reference beam to form a hologram. Whenever the plate is rotated 180.degree. to an inspection orientation, a reconstructed imate of the photomask appears at the location where the photomask was positioned during exposure.

Abstract: An optical display system employs a holographic optical element that has a holographic fringe pattern which is coordinated with the phosphor emission peak of a cathode ray tube to eliminate perceptible variations in image brightness. The holographic optical element has a reflection characteristic that defines two diffraction efficiency peaks which are resolved by a low diffraction efficiency dip that is interposed between them. The optimum wavelength spacing between the two diffraction efficiency peaks for a given wavelength spacing is determined by computing for all observer head positions and look angles of concern the differences among the areas under the integrated efficiency characteristics for the reflection characteristic of the holographic optical element and the phosphor emission characteristic of the image-producing cathode ray tube. The optimum wavelength spacing is that which provides the desired variation among the computed difference values, which respresent the display brightness uniformity.

Abstract: There is disclosed herein a holographic optical element (HOE) which is particularly useful for head up display (HUD) systems and similar systems wherein the holographic element is used in a transmission mode as well as in a reflection mode. The element introduces little or no flare when bright light sources are viewed in transmission. The reduction in flare is accomplished by constructing the holographic element so that the fringe density (or spatial frequency) is low or zero at the surfaces of the hologram which forms the holographic element, or stated differently, the fringes in the hologram are formed parallel or substantially parallel to the surfaces of the hologram so that no fringes or very few fringes intersect the surfaces of the hologram. This is accomplished through control of the construction geometry to appropriately orientate the fringes, and a suitable fringe density is approximately two or fewer line pairs per millimeter for a typical application.

Abstract: An acousto-optic beam deflector comprises an optically active stress optic medium, such as crystalline quartz, driven by a longitudinal acoustic wave transducer. The deflector is independent of optical polarization, and therefore both polarization components of an input optical beam, such as a laser beam, are scattered with equal efficiencies.