Patents by Inventor Robert A. Sprague
Robert A. Sprague has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 5612791Abstract: An apparatus for imaging books or other bound documents with minimal stress being applied to the book structure, and for successively imaging and turning pages of a book by means of an air jet system. The book imager includes a support, for placement of a book in an open position, an imager having opposed imaging surfaces capable of simultaneously imaging the entire exposed, facing adjacent pages of the book in a distortion preventing manner, and an air jet page turning system. The support and the imager are relatively movable toward and away from one another, from a first position in which imaging is effected, to a second position in which page turning is effected. The air jet page turning system includes a fluffing jet for separating pages, a pick-off jet for separating the topmost page from the fluffed pages, a force applying jet for urging the topmost page into intimate contact with the imaging device and a page turning jet for driving the topmost page to the opposite side of the book.Type: GrantFiled: December 12, 1995Date of Patent: March 18, 1997Assignee: Xerox CorporationInventors: William D. Turner, Robert A. Sprague
-
Patent number: 5550656Abstract: A full color display is disclosed having a high efficiency light source optically coupled by a light coupling lens array to the active matrix of pixel elements of an image forming means such as a transmissive liquid crystal light valve. The light source is comprised of a patterned matrix of individual, primary colored visible radiation emitters, such as individual phosphor elements, arranged in a manner suitable for the human eye to integrate the individual primary colored lights into a single mixture color. The light coupling lens array collects substantially all of the light rays emitted from each primary colored light emitter and focuses them on a respective one of the transparent electrodes in the active matrix, as a real image smaller than the size of the electrode. A suitable light coupling lens array is a gradient index lens array, a multiple layer, two dimensional array of microlenses functionally analogous to an array of strip lenses, or a microlens array.Type: GrantFiled: May 25, 1995Date of Patent: August 27, 1996Assignee: Xerox CorporationInventors: Robert A. Sprague, RIchard H. Bruce, Louis D. Silverstein
-
Patent number: 5504597Abstract: A full color display is disclosed having a high efficiency light source optically coupled by a light coupling lens array to the active matrix of pixel elements of an image forming means such as a transmissive liquid crystal light valve. The light source is comprised of a patterned matrix of individual, primary colored visible radiation emitters, such as individual phosphor elements, arranged in a manner suitable for the human eye to integrate the individual primary colored lights into a single mixture color. The light coupling lens array collects substantially all of the light rays emitted from each primary colored light emitter and focuses them on a respective one of the transparent electrodes in the active matrix, as a real image smaller than the size of the electrode. A suitable light coupling lens array is a gradient index lens array, a multiple layer, two dimensional array of microlenses functionally analogous to an array of strip lenses, or a microlens array.Type: GrantFiled: June 5, 1995Date of Patent: April 2, 1996Assignee: Xerox CorporationInventors: Robert A. Sprague, Richard H. Bruce, Louis D. Silverstein
-
Patent number: 5504598Abstract: A full color display is disclosed having a high efficiency light source optically coupled by a light coupling lens array to the active matrix of pixel elements of an image forming means such as a transmissive liquid crystal light valve. The light source is comprised of a patterned matrix of individual, primary colored visible radiation emitters, such as individual phosphor elements, arranged in a manner suitable for the human eye to integrate the individual primary colored lights into a single mixture color. The light coupling lens array collects substantially all of the light rays emitted from each primary colored light emitter and focuses them on a respective one of the transparent electrodes in the active matrix, as a real image smaller than the size of the electrode. A suitable light coupling lens array is a gradient index lens array, a multiple layer, two dimensional array of microlenses functionally analogous to an array of strip lenses, or a microlens array.Type: GrantFiled: May 25, 1995Date of Patent: April 2, 1996Assignee: Xerox CorporationInventors: Robert A. Sprague, Richard H. Bruce, Louis D. Silverstein
-
Patent number: 5442467Abstract: A transmissive, backlit color twisted-nematic or super-twisted-nematic liquid crystal display employing a front fiber-optic faceplate as a front retaining element of a liquid crystal cell that increases viewing angle between the display and a viewer while minimizing or eliminating undesirable variations in luminance, contrast ratio and chromaticity is described. This novel configuration effectively decouples the liquid crystal cell and other optical elements behind the front fiber optic faceplate from the angular orientation of the viewer with respect to the display. The liquid crystal display described in this invention further provides a high quality color display, without viewing parallax, using a color selection filter mosaic outside of the liquid crystal cell.Type: GrantFiled: March 21, 1994Date of Patent: August 15, 1995Assignee: Xerox CorporationInventors: Louis D. Silverstein, Thomas G. Fiske, Richard Bruce, Robert A. Sprague
-
Patent number: 5315418Abstract: A full color, liquid crystal display device is disclosed having two optical paths, the first for long (red) and medium (green) wavelength regions of the visible light spectrum, and the second for the short (blue) wavelength region of the visible light spectrum. The two optical paths and their properties are nominally matched to the characteristics of the chromatic and luminance processing channels of the human visual system. The two-path device generates two separate, spatially coherent color images using two liquid crystal light valve image forming sources, without the use of color filters typically found in full color displays. The two images are combined by additive spatial superposition to produce a single, full-spectrum, composite color image. In one embodiment, individual red and green light components from an efficient, patterned backlight of individual red and green light emitters are coupled by a light coupling lens array to respective display pixels in the liquid crystal light valve.Type: GrantFiled: June 17, 1992Date of Patent: May 24, 1994Assignee: Xerox CorporationInventors: Robert A. Sprague, Louis D. Silverstein, Richard H. D. Bruce
-
Patent number: 5264880Abstract: A method for achieving a color projection of an image directs light from a source to a dispersive element and disperses the light received by the element into a spectrum of light having different colors at different angles. Each color band of the resulting spectrum is focused, and the dispersed color bands are modulated in color bands corresponding to those received during the focusing onto a modulating element. Finally, the modulated light beams are recombined for projecting onto a projection surface.Type: GrantFiled: December 30, 1991Date of Patent: November 23, 1993Assignee: Xerox CorporationInventors: Robert A. Sprague, Richard H. Bruce
-
Patent number: 5138340Abstract: A technique for producing pixel patterns at different selected wavelengths. A diode laser is repeatedly pulsed and has its temperature changed from pulse to pulse, which causes the output wavelength to change. This allows pixel patterns to be interlaced by the use of dispersive elements such as prisms in the optical train. A temperature shift of about 15.degree. C. provides a wavelength shift of about 30 angstroms, which is usable. A temperature shift of 20.degree. C.-30.degree. C. or more is preferable. The temperature shifts may be accomplished by supplying specific currents below threshold and above threshold. For two-wavelength operation, the laser is driven at a first bias current below threshold for a first non-illumination interval, at a first pulse current above threshold for a first illumination interval, at a second bias current below threshold for a second non-illumination interval, and a second pulse current above threshold for a second illumination interval.Type: GrantFiled: December 6, 1990Date of Patent: August 11, 1992Assignee: Xerox CorporationInventors: Robert A. Sprague, Mark S. Bernstein, Robert P. Kowalski, David L. Hecht, David L. Steinmetz, David E. Kizer, Robert L. Thornton
-
Patent number: 4795349Abstract: A coded font keyboard design is presented wherein conventional keyboard formats, such as the qwerty keyboard, are coded to produce instructional materials for developmental language education using the periodic code of language elements. A preferred embodiment describes the use of the qwerty keyboard to product all coded symbols used in the periodic table of language elements.Type: GrantFiled: March 16, 1987Date of Patent: January 3, 1989Inventors: Robert Sprague, Joan Sprague
-
Patent number: 4768959Abstract: Apparatus and method used in language skills development are described. A periodic table of forty-five language elements is presented. The periodicity of the elements is described in terms of articulation mechanisms. Photographs of mouth pattern and voice frequency information are provided for each language element. The two major families of vowels and consonants are preserved and emphasized on phonomats. These phonomats are designed to reinforce the relationship among the language elements. Alternate spellings, specially encoded, are provided to enable the student to pronounce new words and sentences based on his prior familiarity with the symbol and sound bets presented on the periodic table of language elements.Type: GrantFiled: October 27, 1986Date of Patent: September 6, 1988Inventors: Robert Sprague, Joan Sprague
-
Patent number: 4730331Abstract: A light source comprises a semiconductor laser having a plurality of deposited semiconductor layers including an active region consisting of a plurality of layers forming at least two quantum wells in the active region. The layers immediately adjacent to the active region provide confinement for light generated in one or more optical cavities established in the active region and propagating between end facets of the source. Means, such as in the form of an antireflection (AR) coating, is provided to convert the semiconductor laser into a superluminescent LED source. Further, means is provided to broaden the wavelength spectral emission from the source by rendering the energy levels present in the quantum wells to be at different levels between or among the quantum wells. The resulting output beam has high output intensity and a uniform far field pattern without intensity variation along the beam width particularly useful as a superluminescent LED source for electrooptic line TIR modulators and line printers.Type: GrantFiled: June 16, 1986Date of Patent: March 8, 1988Assignee: Xerox CorporationInventors: Robert D. Burnham, Thomas L. Paoli, Robert L. Thornton, Robert A. Sprague
-
Patent number: 4728166Abstract: A multilayer electrode structure is deposited on or supported in intimate contact with an electro-optic element to define a substantially continuous, transformation-free, branching, fringe field controlled electro-optic waveguide. Transformations are minimized because the fringe field induced waveguiding channels all have substantially equal widths and depths, and discontinuities are reduced by providing bridging electrodes to span any gaps that might otherwise exist in the fringe fields.Type: GrantFiled: May 10, 1982Date of Patent: March 1, 1988Assignee: Xerox CorporationInventors: William D. Turner, Robert A. Sprague
-
Patent number: 4718752Abstract: An optical image bar utilizing polarized light and a coherent spatial light modulator, includes birefrigent spatial or angular shearing means for uniformly dividing the spatially modulated radiation of a coherent image bar into a pair of laterally offset, redundantly modulated, orthogonally polarized optical field distributions. Imaging optics, which include any spatial filtering and/or polarization filtering elements needed for converting those field distributions into correspondingly modulated spatial intensity distributions, bring the filtered field distributions to focus on an output image plane, thereby producing redundantly modulated, laterally offset, intensity profiles on the output image plane which spatially sum with each other on an intensity basis.Type: GrantFiled: December 23, 1985Date of Patent: January 12, 1988Assignee: Xerox CorporationInventors: Robert A. Sprague, David L. Hecht, L. Prasadam Flores
-
Patent number: 4689291Abstract: Monolithic microlenses and microlens arrays are manufactured on opto-electronic devices and other substrates by using sharp edge pedestals to confine the lateral flow of a molten lens material. The lens material wets the upper surfaces of the pedestals, but the pedestal edges confine the flow, so the lens material conforms to the shape of the pedestal surface and assumes a semi-arcuate profile due to its surface tension. Spin coating and photolithographic patterning may be employed to form the pedestals and to deposit the lens material thereon. The lens material is melted after being deposited, so the pedestals advantageously are stabilized to prevent them from deforming at the temperature of the molten lens material.Type: GrantFiled: August 30, 1985Date of Patent: August 25, 1987Assignee: Xerox CorporationInventors: Zoran D. Popovic, Robert A. Sprague, G. A. Neville Connell
-
Patent number: 4663738Abstract: A block oriented solid state optical memory having a distributed data storage architecture comprises a lens array including a plurality of laterally separated lenslets which have numerical apertures selected to cause them to focus essentially diffraction limited images of a photoemitter array in parallel onto laterally displaced sections of a data mask, so that the images optically align with respective photosensors. The lenslets are formed on the first surface of the lens array, and the data mask is supported on or very close to the last surface of the lens array to minimize the scattering of reflected light. An opaque light shield on the first surface of the lens array optically masks the area between the lenslets to eliminate unwanted stray light. Furthermore, in at least some embodiments of the invention, the light shield extends into the apertures of the lenslets to stop them down sufficiently to obtain substantially diffraction limited performance.Type: GrantFiled: December 4, 1984Date of Patent: May 5, 1987Assignee: Xerox CorporationInventors: Robert A. Sprague, John C. Urbach
-
Patent number: 4656641Abstract: A laser cavity optical system is provided for stabilizing the laser far field dominate lobe so that no beam shift occurs. The laser cavity optical system comprises a lens system positioned at one facet of a phased array semiconductor laser for imaging the near field pattern of the laser comprising a single beam waist position in a first spatial direction and reimaging the far field pattern in a second spatial direction after having first focused the far field pattern in the second spatial direction to a single beam waist position. The improvement in the laser cavity optical system comprises a partially reflecting, partially transmitting mirror located at the second spatial direction beam waist position to stabilize the laser beam and prevent laser beam shift at higher operating powers and operating temperatures. Feedback means provided in the system is capable of either spatially or angularly discriminating relative to far field lobes present in a portion of said reflected light output.Type: GrantFiled: February 4, 1985Date of Patent: April 7, 1987Assignee: Xerox CorporationInventors: Donald R. Scifres, Robert A. Sprague
-
Patent number: 4650423Abstract: Apparatus and method used in language skills development are described. A periodic table of forty-five language elements is presented. The periodicity of the elements is described in terms of articulation mechanisms. Photographs of mouth pattern and voice frequency information are provided for each language element. The two major families of vowels and consonants are preserved and emphasized on phonomats. These phonomats are designed to reinforce the relationship among the language elements. Alternate spellings, specially encoded, are provided to enable the student to pronounce new words and sentences based on his prior familiarity with the symbol and sound bets presented on the periodic table of language elements.Type: GrantFiled: October 24, 1984Date of Patent: March 17, 1987Inventors: Robert Sprague, Joan Sprague
-
Patent number: 4638334Abstract: An electro-optic line printer comprises a recording medium, a multigate line modulator for printing picture elements or pixels in spatially predetermined positions along a printing axis and an LED side-facet source characterized by having high output intensity and a uniform far field emission and optical means to collimate the far field emission in the tangential direction and focus the near field in the sagittal direction onto the modulator. The optical means comprises a first lens system to collect the light emitted from the LED source in both the tangential and sagittal directions and a second toric lens to collimate the light into a sheetlike beam in the tangential direction and to focus the light in the sagittal direction to a line image at the modulator. Imaging means is optically aligned between the modulator and the recording medium for imaging the modulator onto the recording medium.Type: GrantFiled: April 3, 1985Date of Patent: January 20, 1987Assignee: Xerox CorporationInventors: Robert D. Burnham, Thomas L. Paoli, Robert L. Thornton, Robert A. Sprague
-
Patent number: 4633445Abstract: An eraseable solid state optical memory has an array of selectively energizeable photoemitters which are imaged by suitable imaging means onto a data mask to optically address data stored thereon. To that end, the data mask is an eraseable optical recording medium, such as a tellurium suboxide or other chalcogenide material. A data writer is provided for programming, erasing and re-programming the data mask in situ while self-aligning the imaging means with the programmed data mask. The data mask may be erased and/or re-programmed in whole or part, thereby extending the utility of these memories to the storage of data that is subject to change.Type: GrantFiled: December 14, 1984Date of Patent: December 30, 1986Assignee: Xerox CorporationInventor: Robert A. Sprague
-
Patent number: 4622079Abstract: A method consisting of a high temperature diffusion treatment, preferably preceded by a hot isostatic pressing treatment, by which the deleterious effects of hard alpha defects may be substantially reduced or eliminated from ingots of titanium or titanium alloys without adversely affecting the subsequent structure and properties of ingots processed by the method and the homogenized, substantially hard alpha and inclusion-free ingots produced thereby.Type: GrantFiled: March 22, 1985Date of Patent: November 11, 1986Assignee: General Electric CompanyInventors: Winston H. Chang, Robert A. Sprague, Joseph A. Stahl