Abstract: A positioning fixture for a rotary mold provides both rotation and lifting for a mold installed therein. The present fixture is adapted particularly for relatively large molds, as used in the forming of hulls and other large structures for relatively large boats and the like. The positioning fixture basically comprises a frame with an upright at each end, with the mold structure extending between the two uprights. A drive motor is provided to rotate the mold between the two uprights, as desired. In addition to the drive motor, a lift strut or cylinder installed at one end of the device and communicating with the opposite end by a tension member (belt, chain, etc.) lifts both of the mold rotating pins or mechanisms simultaneously. A safety latch or catch is installed at each end of the device, to preclude accidental dropping or falling of the mold when lifted.

Abstract: A multiple track playback headwheel is disclosed for use in a helical scan optical tape recording system. The headwheel includes optical diffraction gratings at the center of rotation of the headwheel positioned normal to the rotational axis. A collimated light beam supplied from a laser external to the headwheel, directed along the rotational axis of the headwheel, is split into a plurality of beams by the gratings. The plurality of beams are imaged at the entrance pupil of the playback objective lens which focuses the beams to diffraction limited spots on the surface of an optical tape having information recorded thereon. The illuminated spots are reflected back through the objective lens and are formed into beams which are directed to an information and tracking detecting apparatus and to a focus detecting apparatus.

Abstract: In an optical scanning system suitable for use in an aircraft for ground contour measurements, wherein the received image from an illuminated ground spot is reflected from a rotating prism onto paraboloidal mirrors which focus the image at a common focal point, and wherein the rotating prism is also used to transmit the scanning spot-illuminating beam, a wedge-shaped light guide accepts the coincident focused images and funnels them into a photoelectric detector. Because the prism rotates at high speed, variations in light signal transit times due to differences in target distance over the range of the scan cycle and due to differences in aircraft altitude cause the image focal point to shift, necessitating a relatively wide rectangular input aperture on the light guide, resulting in the admittance of large amounts of background light in to the detector.

Abstract: An optical scanning system provides an intensity-modulated, illuminated spot for contour measurements using phase detection. Two semiconductor lasers, which are thermally coupled but are electrically isolated, transmit light beams which are translated and separately collimated by the optics of the system. The collimated beams are then combined on adjacent reflecting facets of a rotating polyhedron to form a narrow beam which illuminates a small spot at relatively high intensity. The beam scans across the target surface over an angle of 120 degrees.

Abstract: Defect detection apparatus provides a moving light beam which illuminates the surface of a rotating grooved disc with a light spot spanning a plurality of convolutions of the groove. The beam is translated to rapidly scan the grooved surfaces in a radial pattern. The structure of the groove convolutions, absent any defects, diffracts the incident beam producing a plurality of reflected beams. A first lens, provided in the path of the reflected beams, provides, in a focal plane thereof, a Fourier transformation of the light amplitude data of the respective reflected beams. A second lens, provided in the diffracted beam path downstream of the first lens, provides at the surface of a photodetector, an inverse Fourier transformation which is an image of the scanning spot. Blocking means, placed in the focal plane of the first lens intercept the reflected beams when defect-free groove regions are illuminated, to prevent the conversion of light energy to electric energy by the photodetector.

Abstract: A flat field laser recorder includes means to direct a beam from a laser through an acousto-optic light modulator, an acousto-optic light deflector/modulator, and a beam scanner, to scan-lines on a linearly-moving light-sensitive film. The acousto-optic light modulator is operated by electrical oscillations which are amplitude modulated by a video information signal. The acousto-optic light deflector/modulator is operated by electrical oscillations which are amplitude modulated to provide an automatic brightness control of the beam, and are frequency modulated to provide an automatic scan-line spacing control. In addition, a plurality of simultaneous oscillation frequencies are selectively applied to the deflector/modulator to provide beam spot elongation control in the direction perpendicular to the scan-lines.