By Reflection Patents (Class 359/318)
  • Patent number: 5990990
    Abstract: A system and method generate volumetric, three-dimensional displays, including displays of images or data. An apparent position of a volumetric image is translated by employing an image translation chamber with various combinations of concave and convex reflectors, mirrors, lenses, and/or holographic optical elements. A high-speed opto-mechanical shutter may also be used, as well as acousto-optic modulators (AOMs) for very high-speed intensity modulation of a coherent light beam to generate a periodic pattern of light packets or pulses. Active and passive multi-planar optical elements (MOEs) are also used in either a reflective or a transmissive mode and optionally having interposed layers of switchable liquid crystal material. A multi-planar optical sensor with interposed layers of light-sensitive material may be employed, as well as a gas imaging chamber for displaying the three-dimensional images. The system and method also allow interaction with the volumetric display of an image.
    Type: Grant
    Filed: November 4, 1996
    Date of Patent: November 23, 1999
    Inventor: Allen F. Crabtree
  • Patent number: 5978128
    Abstract: A deformable mirror device for changing a proceeding path of an incident light includes a substrate, a pair of posts protruding from the upper surface of the substrate and spaced a predetermined distance from each other, an electrode formed on the upper surface of the substrate, a reflection mirror arranged to face the electrode by being supported by the posts, and first and second support pieces having predetermined rigidities for supporting the reflection mirror. The support pieces are connected between the reflection mirror and the posts so that an inclination of the reflection mirror can be adjusted by an electrostatic attraction between the electrode and the reflection mirror. The electrode is arranged to be offset from the reflection mirror such that a magnitude of the forces applied to the electrode at the positions between each of the first and second support pieces and the reflection mirror differ from each other.
    Type: Grant
    Filed: August 4, 1998
    Date of Patent: November 2, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-seop Yoon
  • Patent number: 5966235
    Abstract: An optical modulator that contains a flexible dielectric membrane suspended over a substrate. The flexible membrane is made of a dielectric material such as silicon nitride. In one embodiment of the invention, the flexible membrane has an optically active region. A contact region is maintained in the vicinity of the optically active region which is electrically isolated therefrom. The contact region which includes a conductive material draws accumulated charge build-up from the optically active region. In another embodiment a first area of conductive material is formed on at least one surface of the flexible membrane proximate its center. At least one second area of conductive material is formed on at least one surface of the flexible membrane surrounding the first area. The first area of conductive material is kept electrically isolated from the surrounding second area. The first area of conductive material is coupled to an electrical ground.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: October 12, 1999
    Assignee: Lucent Technologies, Inc.
    Inventor: James Albert Walker
  • Patent number: 5949571
    Abstract: The specification describes a double poly Mechanical Anti-Reflection Switch (MARS) device in which shorting between the lower poly metallization and the silicon substrate is prevented by providing an insulating layer on the surface of the silicon substrate.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: September 7, 1999
    Assignee: Lucent Technologies
    Inventors: Keith Wayne Goossen, James Albert Walker
  • Patent number: 5949569
    Abstract: A projection display apparatus includes a light source, a spatial light modulation device, a condenser lens, an aperture stop, and a projecting lens. When the spatial period of complex amplitude modulation in the spatial light modulation device is represented by p, the center wavelength of the incident light is represented by .lambda., and a half angle subtended by an area around an opening edge of the aperture stop at the condenser lens along the first direction is represented by .theta.asx, parameters of the light source, the spatial light modulation device, the condenser lens, the screen, the aperture stop and the projecting lens and a relative positional relationship therebetween are defined such that the following condition is satisfied:0.35<.theta.asx/arcsin(.lambda./p)<0.6.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: September 7, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kei Shimura
  • Patent number: 5943155
    Abstract: The specification describes a double poly Mechanical Anti-Reflection Switch (MARS) device in which transition layers of SiN.sub.x are provided on either side of the air gap, and the thickness ratio of the two transition layers is adjusted to provide a tradeoff between the insertion loss of the device and the optical bandwidth.
    Type: Grant
    Filed: August 12, 1998
    Date of Patent: August 24, 1999
    Assignee: Lucent Techonolgies Inc.
    Inventor: Keith Wayne Goossen
  • Patent number: 5943158
    Abstract: A micro-mechanical, anti-reflective, switched optical modular array that utilizes a continuous, uninterrupted modular membrane across an array of individual modulators. The individual modulators are positioned within an optical window of the device, the optical window being defined by a region of the membrane situated between an array of electrode pairs, where an individual pair of electrodes is used to control an individual one of the modulators. Alternative electrode shapes and fabrication methods are described.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: August 24, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Joseph Earl Ford, Keith Wayne Goossen, James Albert Walker
  • Patent number: 5920421
    Abstract: Thin film AMA in an optical projection system and a method for manufacturing the same are disclosed. The thin film AMA has an active matrix having electrical wiring and a connecting terminal, a first actuator, a second actuator, a supporting element, and a reflecting member. The first actuator and the second actuator are parallely formed and the supporting element is formed in the direction perpendicular to the first actuator and the second actuator. The reflecting member supported by a plurality of posts is tilted by a double displacement, so the quality of a picture projected onto a screen is greatly increased. Also, the first actuator and the second actuator respectively have symmetrical structures centering around the first anchor and the second anchor so that the first actuator and the second actuator have stable structures.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: July 6, 1999
    Assignee: Daewoo Electronics Co., Ltd.
    Inventor: Yoon-Joon Choi
  • Patent number: 5917647
    Abstract: An actuator having an asymmetric rigid structure for changing an optical beam path. The actuator has a base plate installed in a cover, first electrodes installed on an upper surface of the base plate by evaporation, a driving electrode disposed between the first electrodes, a pair of support plates each installed on a respective one of the first electrodes for receiving a voltage from the first electrodes, a reflecting plate disposed between the pair of support plates for reflecting an incident beam emitted from a beam source, and asymmetric members connected to the reflecting plate for adjusting an incident path of the incident beam and an inclination angle of a reflection beam with respect to the incident beam. The actuator can easily adjust the incident path of the incident beam and an inclination angle of the reflection beam with respect to the incident beam by asymmetrically inclining the reflecting plate.
    Type: Grant
    Filed: July 7, 1998
    Date of Patent: June 29, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-seop Yoon
  • Patent number: 5917645
    Abstract: Thin film AMA in an optical projection system and a method for manufacturing the same are disclosed. The thin film AMA has a substrate having an electrical wiring for receiving a first signal applied from outside and transmitting the first signal, a first metal layer having a connecting terminal, a first passivation layer, a second metal layer, an actuator, and a reflecting member. The actuator has a supporting layer, a bottom electrode, an active layer, and a top electrode. An incident light from a light source may be excluded by means of the second metal layer formed on the first metal layer. Mis-operation of actuator due to a photo leakage current caused by an incident light can be prevented before a first signal and a second signal are respectively applied to the bottom electrode and the top electrode.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: June 29, 1999
    Assignee: Daewoo Electronics Co., Ltd.
    Inventors: Dong-Hoon Min, Sang-Wook Park
  • Patent number: 5914804
    Abstract: A mechanical modulator is provided that includes a conductive substrate and at least three multilayer mirrors disposed on the substrate. The mirrors are spaced apart from one another to define upper and lower optical cavities. The upper cavity is formed by an airgap having a variable thickness. The multilayer mirror located above the airgap includes a conductive membrane having an optically transparent portion and a flexible support for orienting the membrane in a first position. Under the action of a bias, the membrane moves to a second position, changing the air gap by a fraction of a wavelength of the optical signal, as measured in air. The change in position of the membrane from the first to the second position causes a change in the total reflectivity of the modulator from a minimum to a maximum value.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: June 22, 1999
    Assignee: Lucent Technologies Inc
    Inventor: Keith Wayne Goossen
  • Patent number: 5914803
    Abstract: Thin film AMA in an optical projection system and a method for manufacturing the same are disclosed. The thin film AMA has a substrate having an electrical wiring and a connecting terminal, an actuator formed on the substrate, and a supporting element for supporting the actuator and for preventing an initial deflection of the actuator. The actuator has a bottom electrode, an active layer, a top electrode. The supporting element has a supporting layer attached beneath the bottom electrode for supporting the actuator, a supporting member for supporting the actuator, the supporting member being formed between the substrate where the connecting terminal is formed and a bottom of a first portion of the supporting layer, and a secondary supporting member for preventing an initial deflection of the actuator, the secondary supporting member being formed between the substrate and a bottom of a second portion of the supporting layer.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: June 22, 1999
    Assignee: Daewoo Electronics Co., Ltd.
    Inventors: Kyu-Ho Hwang, Yoon-Joon Choi
  • Patent number: 5886811
    Abstract: Thin film AMA has a substrate having electrical wiring and a connecting terminal, an actuator formed on the substrate, a supporting element formed between the substrate and the actuator for supporting the actuator, a reflecting member formed on the actuator, and a plurality of posts formed between the actuator and the reflecting member for supporting the reflecting member. The reflecting member is supported by a first post formed on the actuator and by a second post and a third post correspondingly formed on an actuator adjacent to the actuator. So, a deflection or tilting downward of the reflecting member can be prevented so that tilting angle of the reflecting members can be made uniform. Further, as the length of the reflecting member between the first post and the second post, or between the first post and the third post is shorter, the tilting angle of the reflecting member is bigger.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: March 23, 1999
    Assignee: Daewoo Electronics Co., Ltd.
    Inventor: Yong-Ki Min
  • Patent number: 5844711
    Abstract: A tunable spatial light modulator for use with a variable wavelength transmitter having a support surface and a plurality of pixels defining an array thereof upon the support surface. Each pixel has a first conductive element formed to the support surface and a second conductive element spaced away from the first conductive element and movable between first and second portions thereof with respect to the first conductive element, the second conductive element configured to reflect light therefrom.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: December 1, 1998
    Assignee: Northrop Grumman Corporation
    Inventor: William Harrison Long, Jr.
  • Patent number: 5808780
    Abstract: A micromechanical optical switch (30). A reflective surface with two angled reflective surfaces (32,34) positioned opposite a micromechanical device (12). The micromechanical device is positioned such that light input along a path (36) to a first (32) of the two angled reflective surfaces is reflected to the micromechanical device. The micromechanical device then reflects the light to the second (34) of the angled surfaces to be output along another path (38a, 38b). The path (38a, 38b) that the second angled surface (34) outputs the light along is selected depending upon the position of the micromechanical device's reflective member (14). The reflective member (14) deflects from at least one hinge (22) to one of several positions. The number of positions available to the reflective member (14) depends upon the voltage applied to the electrodes (27a, 27b, 27c, 27d). The reflective member (14) makes no contact with any other surfaces, and thereby always returns to a know position upon loss of power.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: September 15, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Terrance Gus McDonald
  • Patent number: 5793520
    Abstract: An optical cross bar switch assembly includes a first lens device (5) in the form of an array of lenslets (5a) operable to receive light from the input optical fiber array (1) in a manner such that the light from each fiber is received and collimated separately by an associated one of the lenslets (5a) with the collimated light from the array (5) being passed to a fan out grating element (3) which angularly diffracts and replicates the light from the input optical fibers.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: August 11, 1998
    Assignee: British Aerospace Public Limited Company
    Inventors: Christopher Stace, Henry J. White
  • Patent number: 5768010
    Abstract: The disclosed acousto-optic scanning device includes a thin film waveguide of piezoelectric material (2), a transducer (3) for generating surface elastic waves, and a high frequency signal generator (4) for generating high frequency signals to be applied to the transducer. Additionally, the device includes a light source (10), light source driver (11) for driving the light source, a prism or grating input and output light couplers (7, 8 or 27, 28) for introducing light emitted from the light source into the thin film waveguide and for outputting light transmitted through the thin film waveguide therefrom. Further, the device includes non-coupled light photodiode detector array (14) for detecting the position and intensity of light which is not coupled by the output light coupling means, and a signal processor for processing information detected by the non-coupled light detector array and generating control signals to correct the position and intensity of coupled light.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: June 16, 1998
    Assignee: Minolta Co., Ltd.
    Inventor: Tsuyoshi Iwamoto
  • Patent number: 5552924
    Abstract: An electrically addressable, integrated, monolithic, micromirror device (10) is formed by the utilization of sputtering techniques, including various metal and oxide layers, photoresists, liquid and plasma etching, plasma stripping and related techniques and materials. The device (10) includes a selectively electrostatically deflectable mass or mirror (12) of supported by one or more beams (18) formed by sputtering and selective etching. The beams (18) are improved by being constituted of an electrically conductive, intermetallic aluminum compound, or a mixture of two or more such compounds. The materials constituting the improved beams (18) have relatively high melting points, exhibit fewer primary slip systems than FCC crystalline structures, are etchable by the same or similar etchants and procedures used to etch aluminum and aluminum alloy, and are stronger and experience less relaxation than aluminum or aluminum alloys.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: September 3, 1996
    Assignee: Texas Instruments Incorporated
    Inventor: John H. Tregilgas
  • Patent number: 5517347
    Abstract: A faceplate (10a) for directly viewing an image generated by a digital micromirror device (10b), which generates images by tilting tiny mirror elements (11) to on or off positions. The faceplate (10a) has a number of optical fibers (12) parallel to each other and closely spaced together. The ends of the optical fibers (12) are the top and bottom surfaces of the faceplate (10a). Both ends of each fiber (12) is sliced at an angle determined by the on position of the mirror elements (11). This permits light to travel down the fibers (12) and be reflected back to the viewer by only those mirror elements (11) that are on.
    Type: Grant
    Filed: December 1, 1993
    Date of Patent: May 14, 1996
    Assignee: Texas Instruments Incorporated
    Inventor: Jeffrey B. Sampsell
  • Patent number: 5508841
    Abstract: A phase-contrast DMD based image system 36 for projecting an amplitude and phase modulated image. A flexure beam DMD array 34 is used to allow analog phase modulation of reflected light 38. The phase modulation is converted to amplitude modulation by the phase-contrast imaging optics including a phase plate 42. The resulting amplitude modulated wave is flicker-free and does not need to be synchronized to optical image sensors.
    Type: Grant
    Filed: January 9, 1995
    Date of Patent: April 16, 1996
    Assignee: Texas Instruments Incorporated
    Inventors: Tsen-Hwang Lin, James M. Florence, Michael Leddy, Mark Boysel
  • Patent number: 5481397
    Abstract: By forming quantum well (QW) structures with two different heterojunctions having different band offsets it is possible to form QWs having, when subjected to optical excitation, dipoles. The presence of a dipole in a narrow enough well results in QWs having absorption edges which, unlike those of conventional QWs can be shifted to the blue by application of an electric field of appropriate polarity.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: January 2, 1996
    Assignee: British Telecommunications
    Inventor: Michael G. Burt
  • Patent number: 5471584
    Abstract: A spatial light modulator of the so-called deformable mirror device (DMD) type has an array of individual mirror ments (20) arranged in lines. The elements are individually driven to change their orientations. Portions (30) of the mirror ments are non-reflecting such as to divide the mirror elements into substantially equal portions forming a greater number of lines of narrower width, with a view to reducing the subjectively visible line structuring.
    Type: Grant
    Filed: August 28, 1993
    Date of Patent: November 28, 1995
    Assignee: Rank Brimar Limited
    Inventors: Peter W. Blaxtan, John Gillespie
  • Patent number: 5463534
    Abstract: An optical system for producing a high power light source comprises a number of laser diodes, or similar sources, which emit light from an emission stripe 8 having a long dimension a (x-axis) and a short dimension b (y-axis) and which have a higher numerical aperture in the y-axis than in the x-axis. The laser beams 9 are collimated by a lens 10 and focused onto an optical fiber by a further lens 20. Prior to the focusing, the collimating beams 11 are anamorphically expanded/reduced by beam shaping means 12 so that the width of each beam 11 in the x-axis is increased in relation to the width in the y-axis. The images 21 produced on the fiber end are thus anamorphically magnified so that thte anamorphic ratio between the magnification of the stripe 8 in the y-axis and in the x-axis is greater than one.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: October 31, 1995
    Assignee: Diomed Limited
    Inventor: Anthony Raven
  • Patent number: 5455709
    Abstract: Total internal light spatial light modulation apparatus includes a light source for projecting infrared light; a prism for reflecting the projected light from an internal surface therein; and an array of pixel posts made of electrostrictive material and positioned proximate a back face of the internal surface for selectively eliminating pixel areas of reflection of the projected light to form an image thereby. A multiplexer is provided to select a set of pixel posts to be electrically charged which corresponds with the image, and electrical contacts are formed on each pixel post no permit electrical charging of each selected pixel post.
    Type: Grant
    Filed: March 23, 1993
    Date of Patent: October 3, 1995
    Assignee: Martin Marietta Corporation
    Inventors: Thomas C. Dula, III, Paul J. Caldwell, Alex E. Bailey
  • Patent number: 5319528
    Abstract: An optical system for producing a high power light source comprises a number of laser diodes, or similar sources, which emit light from an emission stripe 8 having a long dimension a (x-axis) and a short dimension b (y-axis) and which have a higher numerical aperture in the y-axis than in the x-axis. The laser beams 9 are collimated by a lens 10 and focused onto an optical fibre by a further lens 20. Prior to the focusing, the collimating beams 11 are anamorphically expanded/reduced by beam shaping means 12, so that the width of each beam 11 in the x-axis is increased in relation to the width in the y-axis. The images 21 produced on the fibre end are thus anamorphically magnified so that the anamorphic ratio between the magnification of the stripe 8 in the y-axis and in the x-axis is greater than one.
    Type: Grant
    Filed: January 31, 1992
    Date of Patent: June 7, 1994
    Assignee: Diomed Limited
    Inventor: Anthony Raven
  • Patent number: 5311350
    Abstract: The present invention provides an optical device according to this invention comprising a light transmitting optical member of a high molecular material containing mobile ions, and a pair of electrodes formed on surfaces of the optical member, a required potential difference being provided between the electrodes so as to cause ion conduction in the optical member and to reversibly vary a refractive index of the optical member. According to this invention, a refractive index is reversibly varied due to ion conduction, whereby the modulation of a transmitted beam or a reflected beam by the optical device can be reversibly controlled.
    Type: Grant
    Filed: January 16, 1992
    Date of Patent: May 10, 1994
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Mitsuo Hiramatsu, Isuke Hirano, Tatsuo Fujinami
  • Patent number: 5256869
    Abstract: A method and apparatus for performing free space optical interconnection. A micro-mirror type of spatial light modulator has an array of mirror elements, whose height with respect to a deflection plane can be individually adjusted. These heights are adjusted such that an input beam of light is phase modulated, and by interference, it is deflected to a desired detector. More than one input beam can be used with the same spatial light modulator, whose mirror elements are adjusted in patterns for deflecting and focussing to multiple detectors.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: October 26, 1993
    Assignee: Texas Instruments Incorporated
    Inventors: Tsen-Hwang Lin, Gregory A. Magel
  • Patent number: 5255118
    Abstract: A technique for reducing interpixel crosstalk in an electrooptic total internal reflection light modulator image bar. A particular electrode length is selected to tailor a portion of the spatial frequency response of the image bar. The pixel size and quality resulting from a voltage difference between electrodes are determined primarily by the overall image bar spatial frequency response, and a set of preferred physical parameters can be determined by selecting parameter values to provide the desired spatial frequency response. It has been found that a desirable frequency response is one that approximates sin(.pi.Pf) for absolute values of f less than about 1/P, where f is the spatial frequency and P is the minimum pixel pitch. Further, it has been found that a particular electrode length provides the desired response for small absolute values of f. The particular electrode length is approximately E.sup.1/2 P/.gamma.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: October 19, 1993
    Assignee: Xerox Corporation
    Inventor: David L. Hecht
  • Patent number: 5227902
    Abstract: A spatial light modulator which includes a light modulation layer which is interposed between two photoconductive layers and laminated to both layers; the two photo conductive layers have charge images written thereon, respectively, by illumination of a writing light carrying optical information; the illumination direction of the writing light to the photoconductive layers are different from each other; and the two photoconductive layers permit the reading light to pass therethrough. When illuminated by a reading light via either of the first or second photoconductive layers, the light modulation layer optically modulates the reading light in accordance with the first and second charge images, under the presence of a voltage applied to the modulator. Thus it reads read out the first information and second information. The first and second photoconductive layers permit the reading light to pass therethrough.
    Type: Grant
    Filed: May 15, 1991
    Date of Patent: July 13, 1993
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Itsuo Takanashi, Shintaro Nakagaki, Ichiro Negishi, Tetsuji Suzuki, Fujiko Tatsumi, Ryusaku Takahashi, Keiichi Maeno
  • Patent number: 5222071
    Abstract: The invention relates to an apparatus including a semiconductor grating whose optical properties can be changed electrically in order to steer a diffracted laser beam with no moving parts. Lithographically defined portions, stripes or areas formed in a semiconductor quantum well region used in association with selectable voltage supply means enable control of the optical characteristics of the grating. The optical properties of the semiconductor quantum well region vary in response to variations in voltage applied to the areas which in turn change the transmissivity or reflectivity of the areas. By selectively applying voltages, the diffraction pattern obtained in the far-field from illuminating the areas is thus controlled and beam steering results. By using a two-dimensional array of areas, or alternatively using two such one dimensional arrays, beam steering in two dimensions may be accomplished.
    Type: Grant
    Filed: February 21, 1991
    Date of Patent: June 22, 1993
    Assignee: Board of Trustees Leland Stanford, Jr. University
    Inventors: Bardia Pezeshki, James S. Harris, Jr.
  • Patent number: 5191464
    Abstract: The electrooptic internal reflection modulator of the present invention provides a technique for reducing interpixel crosstalk by using a compensation filter to help define the spatial frequency response of an image bar. The diffraction efficiency of the system is in part defined by a set of properties of the modulator, the illumination and the imaging subsystems, and is characterized by a spatial frequency response. It has been found that a desirable frequency response is one that approximates sin(.pi.Pf) for absolute values of f less then 1/P, where f is the spatial frequency and P is the minimum pixel pitch.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: March 2, 1993
    Assignee: Xerox Corporation
    Inventor: David L. Hecht
  • Patent number: 5189548
    Abstract: Increasing the addressing capability of an optical image bar having a particular pixel center-to-center spacing (pixel pitch) is accomplished by employing a plurality of N electrodes per pixel. Compared to an optical image bar with one electrode per pixel, this provides N times as many locations for the electric potential transition which establishes the center of the pixel. The provision of multiple electrodes per pixel interval can be used to implement interlacing.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: February 23, 1993
    Assignee: Xerox Corporation
    Inventor: David L. Hecht
  • Patent number: 5157543
    Abstract: An apparatus for changing the direction of an optical beam comprises a thin film grating deflector; an optical energy source for providing optical energy to strike the deflector at a first angle with respect to gratings of the deflector and to exit the deflector at a second angle with respect to the gratings; and elements for applying a voltage to the deflector to vary the second angle. The optical energy source preferably comprises a laser diode; and a collimator for coupling energy from the laser diode to the grating deflector. The grating deflector is a planar waveguide including a plurality of stacked quantum wells formed of GaAs separated by barriers of AlGaAs. Optical energy provided to the grating deflector in a first direction is deflected in a second direction. These directions define a plane in which the waveguide is disposed. The quantum wells are stacked in a direction perpendicular to a plane of the waveguide.
    Type: Grant
    Filed: December 10, 1990
    Date of Patent: October 20, 1992
    Assignee: International Business Machines Corporation
    Inventors: Tadashi Fukuzawa, Satoru S. Kano, Yutaka Takahashi
  • Patent number: 5153770
    Abstract: The TIR modulator has an electrode array distributed across an area of the reflecting surface of the electro-optic material. The electrode array has interdigitated electrodes extending inward from a rectangular-shaped outer electrode conducting block and outward from a diamond-shaped inner electrode conducting block. A diamond-shaped area with no electrodes is preferably symmetrically within the inner electrode conducting block of the electrode array on the reflecting surface. The uniform voltage difference between the electrodes and the varying lengths of the electrodes creates a fringe electrical field in the electro-optical material and an optical phase grating to diffract the incident light on the reflecting surface. The zero order nondiffracted light becomes the output beam. The optical phase grating will control the incident beam's optical profile at the modulator (near field) and hence the imaged spot size at a focus at the image plane (far field).
    Type: Grant
    Filed: June 27, 1991
    Date of Patent: October 6, 1992
    Assignee: Xerox Corporation
    Inventor: Ellis D. Harris
  • Patent number: 5148157
    Abstract: It is possible to control the amplitude and phase modulation of light independently and simultaneously. The invention described here details how to do so by dividing a picture element into smaller modulating elements, providing independent addressing for each element, setting the necessary angle for each element and then resolving them into the picture element. The invention also show one embodiment of the invention.
    Type: Grant
    Filed: September 28, 1990
    Date of Patent: September 15, 1992
    Assignee: Texas Instruments Incorporated
    Inventor: James M. Florence
  • Patent number: 5142303
    Abstract: There is disclosed a deformable mirror device (DMD) exposure unit and method of operation for use in a xerographic printing system. The exposure unit is constructed with an integral unmodulated light source condensing light onto a substrate containing, in one embodiment, a multi-row set of deflectable mirrors. The deflection of each mirror is controlled by electronic circuitry established on the same monolithic integrated substrate. The substrate is arranged with mirror elements which can be adjusted easily during assembly to eliminate time consuming construction or maintenance routines. An optic structure, using integral light baffles and deflection edges, assures the proper contrast and light energy level at the image. In the case of multiple rows of pixels, the on-chip circuitry acts to reregister the spatially separated images through a suitable time delay.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: August 25, 1992
    Assignee: Texas Instruments Incorporated
    Inventor: William E. Nelson