Abstract: A front projection screen for pictorially displaying upon a front face of the screen an image projected onto the front face from a projector comprises a backing member having a front reflective surface and a polarization rotation plate overlaying the reflective surface for rotating the plane of polarization of light reflected from the surface. A sheet of lenticular lenses overlays the polarization rotation plate and a polarizing film overlays the lenticular lens sheet. The polarizing film has non-polarizing segments at a focal point of each of the lenticular lenses so that light from the projector is not attenuated by the film while light from other sources is attenuated.

Abstract: An ultrasonic system and method for imaging a surface wherein a C-mode ultrasonic scan is performed over a fixed area of the surface and range gating is applied to that area to a given depth below the surface. For use of the system and method in fingerprint imaging, a live finger is placed upon a sensitive surface, the portion of the finger on the surface is scanned using the ultrasonic energy, and ultrasonic energy returned from the finger portion is received to capture an electronic image of the pattern of ridges and valleys of the fingerprint.

Abstract: A scan converter capable of converting from any of several input scan formats to a fixed output format, which may or may not have the same number of lines as the input, derives a current displayed (output) field or frame by interpolation from the current field of an input whose vertical scan frequency is the same as that of the output. The converter recognizes the number of lines in the input and automatically derives the appropriate interpolation routine to make the conversion to a desired fixed output format. Because the vertical scan frequency is the same for the input and output, only a few lines of storage, instead of the frame store usually required, are needed to accomplish conversion with results comparable to that attainable when a full frame of information is stored.

Abstract: Method for producing a large capacity solid-state memory wherein thin film technology is used to form a plurality of large-area arrays of memory cells, each of which is fabricated in a continuous process on a thin flexible substrate to form an elongate tape. The plurality of tapes are assembled into a compact package by winding them, one upon the other, into a spool which is placed in a suitable housing.

Abstract: Apparatus for horizontally scanning an image corresponding to electronic video input information utilizing a Bragg Diffraction cell in which collimated light from a laser directed through the cell is modulated by a real-time fourier transform of a line of video input information, thereby to produce a one line acoustic hologram in the cell which is reconstructed at a infinity as a stationary image corresponding to the horizontal line of video information. Using a suitable lens system, the stationary image is re-imaged at a plane positioned at a fixed distance from the Bragg Diffraction cell. The scanner is useful in image projection systems, in which the horizontal line image is vertically scanned by a galvanometer driven mirror vibrating in synchronism with the vertical blanking interval of the input video.

Abstract: A large capacity, solid-state memory device is disclosed in which information is stored in a plurality of large-area arrays of memory cells, each of which is a crossed-wire matrix of memory cells fabricated in a continuous process on a thin flexible substrate, using thin film transistor technology, to form an elongate tape. The plurality of tapes are assembled into a compact package by winding them, one upon the other, into a spool, which is placed in a suitable housing which for apparatus having a storage capacity of one terabit has a volume of about 100 cubic inches.

Abstract: A color camera having good to-noise ratio and good resolution uses a single CCD image sensor chip with an optical color filter having a multiplicity of clusters of three circular areas, each of a different characteristic color, hexagonally arranged so as to form a multiplicity of horizontal rows each horizontally offset from the rows immediately above and below it by one-half the diameter of the circular areas. The circular areas have substantially the same diameter as the pixels of the CCD sensor. The camera includes mechanical apparatus for providing motion of the image with respect to the chip in a circle that is about one pixel in diameter, causing the image to rotate sequentially through the three different colored pixel fields of a cluster. Signals clocked out of the CCD sensor are processed to obtain R, G and B signals and low and high resolution luminance signals which are added to derive a final luminance signal.

Abstract: A projection system which produces a color image on a screen corresponding to an applied color signal. In a preferred embodiment, light beams from a source of white light are separated by a dichroic mirror into two beams, one containing green and the other containing blue and red. The beam containing green illuminates a first active matrix liquid crystal panel which contains electrodes which define a diffraction grating having parameters corresponding to green, and the beam containing blue and red illuminates a second active matrix liquid crystal panel which contains electrodes which form two separate diffraction gratings, one having parameters corresponding to red and the other having parameters corresponding to blue. As each beam passes through its respective LC panel its transmittance is modulated in accordance with video information signals applied to the panels, and the red and blue colors are selected by diffraction.

Abstract: An ultrasonic system and method for imaging a surface wherein a C-mode ultrasonic scan is performed over a fixed area of the surface and range gating is applied to that area to a given depth below the surface. For use of the system and method in fingerprint imaging, a live finger is placed upon a sensitive surface, the portion of the finger on the surface is scanned using the ultrasonic energy, and ultrasonic energy returned from the finger portion is received and converted into spatial frequency components to determine the pattern of ridges and valleys of the fingerprint.

Abstract: A solid state light modulator apparatus is disclosed for displaying images represented by video signals. The system includes an array of semiconductor devices having electrodes which extend over the tops of their respective devices. The devices are used, in conjuction with related circuitry, for applying sampled video signals to the electrodes. The resulting charge pattern deforms a conductive/reflective layer, and the deformations are converted to a viewable image by an optical system. The electrodes are divided into separate fingers which decreases the effective grating line spacing of the light modulator and accordingly increases resolution. Electrodes of the array have at least three electrically connected fingers such that at least one of the fingers is interleaved with fingers of an electrode in a row above in said array and at least another of said fingers is interleaved with fingers of an electrode in a row below in said array.

Abstract: A solid state light modulator apparatus for displaying images represented by video signals. The system includes an array of semiconductor devices having electrodes which extend over the tops of their respective devices. The devices are used, in conjunction with related circuitry, for applying sampled video signals to the electrodes. The resulting charge pattern deforms a concuctive/reflective layer, and the deformations are converted to a viewable image by an optical system. The electrodes are divided into separated fingers which decreases the effective grating line spacing of the light modulator and accordingly increases resolution. Also, the electrodes are at two different levels, and the spurious light immunity of the light modulator is improved.

Abstract: A system and method are disclosed for transmission and reception of high definition television signals. A standard television signal is transmitted over a first transmission frequency channel, and an enhancement signal, to be used for enhancing the standard signal to obtain a high definition signal, is transmitted over a second transmission frequency channel that is non-adjacent to the first transmission frequency channel. A code signal, which identifies the second transmission frequency channel, is combined into the standard television signal before transmission. The code signal is recovered at the receiver, and used to automatically tune the receiver to also receive the enhancement signal sent over the second transmission frequency channel. A second code signal, representative of other information, such as the portion of the second transmission frequency channel that contains the enhancement information, can also be sent with the standard signal.

Abstract: A technique is disclosed for generating a progressively scanned video signal from an interlaced signal without the need for motion-adaptive processing. Low resolution information is obtained from the current interlaced field, and the remaining detail information is obtained from a stored signal that includes a prior field or fields. The obtained signal can then be displayed with progressive scanning at full resolution and without motion artifacts.

Abstract: An analog video frame store, resident in certain types of video displays, is used to obtain video signal noise reduction. A frame storage system has an array of semiconductor-controlled storage units for receiving and storing frames of video information as a pattern of stored charge. A circuit is provided for applying sampled portions of the video signals to respective ones of the elemental storage units of the frame storage system. The circuit is operative to apply the sampled portions of the video signals to their respective semiconductor unit storage regions with a time constant for each particular storage unit that depends upon the difference between the sampled signal level being applied to the particular storage unit and the signal level stored at the particular storage unit.

Abstract: A method and apparatus is disclosed for improving video signals. High spatial frequency portions of color-representative signals are added to a luminance channel in order to improve the apparent sharpness of images having saturated colors, improve monochrome presentations of color images, and/or reduce the bandwidth necessary to represent color-representative signal components of video signals.

Abstract: Apparatus and method are disclosed for encoding and decoding a video signal. The standard resolution chrominance and the detail component of standard resolution luminance are encoded and transmitted in a way which allows them to be separated at the receiver without cross color. A conventional type of NTSC transmission is modified by adding together the color and the luminance signals above 2.5 megahertz, the information being repeated for two successive frames, with the color carrier reversed in phase as it normally does. At the receiver, successive frames are added and subtracted to recover the color and the luminance above 2.5 megahertz.

Abstract: An apparatus and method for generating video signals using an improved camera system is disclosed. The camera system includes first and second video imaging devices which are scanned at different scan rates. An optical switching system directs light from the scene alternately in time to the first and second video imaging devices, and makes efficient use of available light from a scene being imaged. In an embodiment of the invention, the optical switching system includes a reflective shutter.

Abstract: An apparatus and method for generating video signals using an improved camera system is disclosed. Video recording techniques which save bandwidth, and a temporal filter which is tailored to the eye's temporal response are also disclosed. In the camera apparatus, an optical means directs light from a scene to both a first video imaging device operating at a relatively fast frame rate and a second video imaging device operating at a relatively slow frame rate. The outputs of the two video imaging devices can be combined to obtain a high definition video signal.

Abstract: A solid state light modulator apparatus and method for displaying images represented by video signals. The system includes an array of semiconductor devices having electrodes arranged in a diagonal pattern, the devices being used, in conjunction with related circuitry, for applying sampled video signals to the electrodes. The resulting charge pattern deforms a reflective layer, and the deformations are converted to a viewable image by an optical system. In a preferred embodiment, every other line of a frame is grounded for one field, thereby achieving an improvement in the dynamic resolution of the display.

Abstract: A solid state light modulator is disclosed for displaying images represented by video signals. The system includes an array of semiconductor devices having electrodes arranged in a diagonal pattern, the devices being used, in conjunction with related circuitry, for applying sampled video signals to the electrodes. The resulting charge pattern deforms a reflective layer, and the deformations are converted to a viewable image by an optical system. An improved technique of biasing the light modulator structure permits operation with better sensitivity and at lower operating voltage.