Plzt Material Patents (Class 359/323)
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Patent number: 6222667Abstract: A two-dimensional light valve array comprising a pattern of reduced electrode spacing solid state light valves formed using semiconductor processing techniques, and a method of making same. The electrodes are recessed into channels in an electro-optic substrate, such as lanthanum modified lead zirconate-titanate (PLZT). A first set of electrodes are deposited in a comb-shaped configuration into parallel and orthogonal channels etched into the PLZT substrate. A second set of deposited electrodes are bands running in alternating channels between the teeth of the first set of electrodes. An insulating material isolates the two sets of electrodes. An applied voltage between the electrodes induces bi-refringence in the PLZT and affects light transmissivity through the light valve at that location. The array is activated electronically by means of matrix addressing and controlled by means of a microcomputer and appropriate software.Type: GrantFiled: February 9, 1999Date of Patent: April 24, 2001Assignee: Advanced Optics Electronics, Inc.Inventor: Garth W. Gobeli
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Patent number: 6211993Abstract: A solid state device used to modulate the intensity of reflected or transmitted light by modulating with an external voltage the optical thickness of a thin film ferroelectric placed in an etalon cavity is disclosed. The device is constructed by selecting a generally planar supporting substrate, preferably silicon or sapphire in order to be compatible with silicon integrated circuits. A dielectric stack consisting of alternating layers of different index of refraction materials, also specifically selected to be compatible with later growth of the thin film ferroelectric, is deposited thereon to form a partially reflective and partially transmitting mirror, followed by a transparent electrically conductive layer. The thin film ferroelectric is deposited on the conductive layer, followed by a second transparent conductive layer and a second dielectric stack. Leads are connected to the conductive layers and in turn to a voltage generator.Type: GrantFiled: October 19, 1999Date of Patent: April 3, 2001Assignee: NZ Applied Technologies CorporationInventors: Feiling Wang, Gene H. Haertling
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Patent number: 6201634Abstract: The present invention provides a method for calculating the birefringence of an optical element and selecting the direction of minimum birefringence in the optical element. A material for manufacturing the optical element is a fluoride single crystal with a birefringence value that is reduced compared to conventional materials. The fluoride single crystal is cut from a fluoride single crystal ingot obtained by crystal growth so that the {111} crystal planes are two parallel planes, after which the optical performance is improved by subjecting this material to a heat treatment. The birefringence of the optical element is calculated by converting known piezo-optical constants in a specified three-dimensional orthogonal coordinate system for the optical material into piezo-optical constants in an arbitrary three-dimensional orthogonal coordinate system.Type: GrantFiled: March 11, 1999Date of Patent: March 13, 2001Assignee: Nikon CorporationInventors: Shigeru Sakuma, Shuuichi Takano
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Patent number: 6034761Abstract: An apparatus for measuring displacement information of an object. The apparatus has a light source emitting a light beam, an electro-optical crystal member, a voltage applying system for imparting a predetermined frequency difference between light beams passing through two different areas in the electro-optical crystal member, and a light receiving system for receiving scattered light from the object to which the two light beams emergent from the electro-optical crystal member have been projected. The electro-optical crystal member is disposed so that a light beam from the light source may partly enter the two different areas to form the two light beams to which the predetermined frequency difference is imparted. The displacement information of the object is obtained from the scattered light received by the light receiving system.Type: GrantFiled: February 11, 1998Date of Patent: March 7, 2000Assignee: Canon Kabushika KaishaInventor: Makoto Takamiya
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Patent number: 5920662Abstract: The invention concerns a planar electro-optical light-beam deflector with a line of prismatic deflectors, arranged side by side, exhibiting electrodes to which an electric voltage can be applied. It is essential to the invention that the light beam is conveyed in a Z-cut lithium niobate or lithium tantalate crystal, preferably in a monomodal layer waveguide extending along the surface of the latter, the prismatic deflectors each consisting of two triangular or prismatic zones in which a largely uniform polarization direction is generated by inversion of the polarization direction determined by the E-field vector in domains with spontaneous polarization in the opposite direction, each triangular zone exhibiting polarization in the direction opposite to that of the one adjacent to it, and that a rectangular electrode covering the triangular zones is attached to the upper side of the crystal and a counterelectrode to the lower side of the same.Type: GrantFiled: August 29, 1997Date of Patent: July 6, 1999Assignee: Fraunhofer-Gesellschaft zur Forderung der angewandten Forschung e.V.Inventor: Vladimir Hinkov
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Patent number: 5900966Abstract: An acousto-optic modulator having an ultrasonic medium for controlling light from a light source by diffracting the light and a transducer portion having electrodes for generating an acoustic wave in the ultrasonic medium, wherein the transducer portion includes two transducers each having an electrode. The AOM is provided with two electrodes by using two transducers, thereby facilitating impedance matching with a driver. The two transducers may be installed so that their polarization directions are opposite to each other, thereby obtaining maximum power transfer to the ultrasonic medium.Type: GrantFiled: August 15, 1997Date of Patent: May 4, 1999Assignee: Samsung Electronics Co., Ltd.Inventors: Yong-hoon Kim, Hang-woo Lee
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Patent number: 5850308Abstract: An access system based on piezo-electric transducer assembly or electro-optic device light beam deflector assembly which on application of electric signals deflects light beams, which are then passed through total internally reflecting surfaces to increase the separation between beams, is described. The light beams fall on large area information storage surface, such as optical disk or magnetic disk, for the purpose of reading and writing. The access time to the information is very fast. The nature of the reflected light from the memory surface is detected to read the digital signals stored on the surface as is conventionally done in the art. Except for the small friction-free movements of the piezo-electric transducers there are no moving parts for access to the storage surface. Instead of the memory surface a screen may be placed when tthe light beams can be used after large separation to form a fast display.Type: GrantFiled: June 1, 1995Date of Patent: December 15, 1998Inventor: Pranab Dastidar
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Patent number: 5774259Abstract: A photostrictive device controller and a photostrictive device control method, which can produce a fast response without causing a sharp temperature rise when driving the photostrictive device. The photostrictive device controller comprises: a light source 2 for applying light to the photostrictive device 1 that, upon receiving light, produces a photostrictive effect; an illumination optics 3 for introducing light from the light source 2 onto the photostrictive device 1; and a control device 4 for controlling the energy density of light applied to the photostrictive device 1. The control device 4 of the controller controls the illumination optics device 3 to lower, at a point close to where the photostrictive effect of the photostrictive device 1 is saturated, the energy density of the irradiated light to a level at which the elongation caused by heat can be ignored.Type: GrantFiled: September 25, 1996Date of Patent: June 30, 1998Assignee: Kabushiki Kaisha TopconInventors: Susumu Saitoh, Michiko Nakanishi
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Patent number: 5734491Abstract: An electro-optic modulator (30) with a threshold bias. A PLZT substrate (14) has a plurality of first electrode pairs (12a) and (13a) on a first surface, and a plurality of second electrode pairs (12b) and (13b) on a second surface, which are aligned with the first plurality of electrode pairs. First and second electrode pairs are electrically isolated. A negative bias voltage is applied to the first plurality of electrode pairs (12a) and (13a). A positive bias voltage is applied to the second plurality of electrode pairs (12b) and (13b), which is approximately equal in magnitude to the first bias voltage. The bias voltage reduces the signal voltage necessary for optical transmission and improves the linearity of the electro-optic modulator (30).Type: GrantFiled: May 30, 1996Date of Patent: March 31, 1998Assignee: Eastman Kodak CompanyInventor: John Richard Debesis
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Patent number: 5731890Abstract: A compound having nonlinear optical properties of the general formula:Ar.sup.1 CR.sup.1 .dbd.CR.sup.2 (Ar.sup.2 CR.sup.3 .dbd.CR.sup.4).sub.n Ar.sup.3 (I)wherein, n represents a whole number; R.sup.1, R.sup.1, R.sup.3 and R.sup.4 groups are independently selected from H, branched aliphatic, straight chain aliphatic, branched silane or straight chain silane; Ar.sup.1 and Ar.sup.3 are aromatic radicals having a substituent in at least one position adjacent to a site of attachment of the C.dbd.C double bond and having at least one electron withdrawing or electron donating substituent in at least one of the remaining positions; Ar.sup.2 is an aromatic radical having a substituent in at least one position adjacent to a site of attachment of the C.dbd.C double bond; with the proviso that the substituent in at least one position adjacent to the site of attachment of the C.dbd.C double bond and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 groups are sufficiently large to cause Ar.sup.1, Ar.sup.2 and Ar.sup.Type: GrantFiled: September 10, 1996Date of Patent: March 24, 1998Assignee: The University of ToledoInventors: James E. Gano, Padmanabhan Sekher
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Patent number: 5668657Abstract: The unique properties of quadratic lead lanthanum zirconate titanate (PLZT) compositions make feasible the development of phased array optical scanners. Two implementations of integrated PLZT phased array scanners as two-port and three-port devices are presented. The three-port offers a significant reduction in the maximum electrode voltage required to effect a specific scan angle. The maximum electrode voltage of the PLZT phased array scanner is characterized in terms of the resolution of the scanner.Type: GrantFiled: February 5, 1996Date of Patent: September 16, 1997Assignee: The United States of America as represented by the Secretary of the Air ForceInventor: Pierre J. Talbot
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Patent number: 5631735Abstract: A multi-slit type spectrometer includes a light diffracter which diffracts an incident light according to wavelengths; an optical shutter array member including a plurality of optical shutter elements arranged in correspondence with wavelength bands diffracted by the light diffracter, operable to transmit an incident ray according to an applied voltage, and made of PLZT. A zone of a given number of adjacent optical shutter elements is applied with a voltage corresponding to the wavelength bands of the rays incident upon the zone of adjacent optical shutter elements at a specified timing so that the rays respectively pass through or are reflected at the optical shutter elements. A signal processor receives the ray which has passed through or has been reflected at each optical shutter element and outputs an electrical signal according to the intensity of the received ray.Type: GrantFiled: May 16, 1996Date of Patent: May 20, 1997Assignee: Minolta Co., Ltd.Inventor: Yoshiroh Nagai
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Patent number: 5585961Abstract: In a photostrictive device whose light-irradiated surface is irradiated with a beam of light with a specified wavelength to produce a photostrictive effect, the light-irradiated surface is formed with a surface roughness Ra related to the wavelength of light. This increases the light absorption of the photostrictive device, thereby improving the responsiveness.Type: GrantFiled: July 31, 1995Date of Patent: December 17, 1996Assignee: Kabushiki Kaisha TopconInventors: Susumu Saitoh, Michiko Kametani
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Patent number: 5481398Abstract: An electro-optic imager, used for exposing photosensitive media, wherein a modulator, e.g. an array of PLZT light valves, is used to modulate one or more light beams. Temperature control is applied to the modulator to reduce or eliminate variations in response characteristics which would otherwise change the color balance of the final print from the desired color balance.Type: GrantFiled: January 13, 1994Date of Patent: January 2, 1996Assignee: Schoonscan, Inc.Inventor: David J. Schoon
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Patent number: 5450230Abstract: The present invention relates to a light shutter array which has shutter elements made of an electro-optical material. The quantity of light transmitted by each shutter element in the array is measured, and a limit is set relative to the smallest measured value such that the transmitted light quantity distribution of the light shutter array would be regarded substantially even if all shutter elements transmitted light within the limit. To achieve such a substantially even distribution, shutter elements which transmit light over the limit are subjected to trimming. Since trimmed regions on a shutter element do not transmit light, the quantity of light transmitted through a trimmed shutter element is lowered in proportion to the area of the trimmed region. Alternatively, individual electrodes and/or portions of a common electrode corresponding to the shutter elements which transmit light over the limit are trimmed.Type: GrantFiled: October 19, 1992Date of Patent: September 12, 1995Assignee: Minolta Camera Kabushiki KaishaInventors: Tomohiko Masuda, Ken Matsubara, Hirohisa Kitano, Masazumi Morishita
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Patent number: 5387997Abstract: An optic modulator having a transparent piezoelectric substrate, an active multiple quantum well (MQW) epilayer with bottom electrical contacts bonded to the substrate, wherein the substrate is cut such that its thermal expansion coefficient is matched or roughly matched to that of the MQW epilayer in the direction parallel to the long axes of the bottom contacts and so that the piezoelectrically-active direction of the substrate is normal to the long axes of the bottom contacts. In order to control the bias of the MQW epilayer a transparent contact is disposed over the MQW epilayer. In operation, the piezoelectric substrate, when activated, will displace an anisotropic strain on the MQW epilayer which will break the rotational symmetry in the plane of the MQW. This will result in anisotropic mixing of the heavy and light holes in the MQW epilayer and thus, will result in an anisotropic excitonic absorption of light normal to the MQW epilayer.Type: GrantFiled: November 29, 1993Date of Patent: February 7, 1995Assignee: The United States of America as represented by the Secretary of the ArmyInventors: Gerald J. Iafrate, Mitra Dutta, Hongen Shen, Michael A. Stroscio, Arthur Ballato
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Patent number: 5221989Abstract: A spatial light modulator comprises a plate of non-ferroelectric PLZT ceramic. An array of pixels is formed by depositing a reflecting coating in the desired array on one side of the plate. A longitudinal electric field is applied so that the light entering the plate from the side opposite the reflecting coating experiences a polarization-independent refractive index change when the electric field is applied as it propagates parallel to the electric field. The required voltages may be decreased when a partially reflecting coating is deposited on the side opposite the reflecting coating. Grooves in the plate effectively isolate the pixels from electrical and mechanical crosstalk.Type: GrantFiled: November 13, 1991Date of Patent: June 22, 1993Assignee: Northrop CorporationInventors: Eddy A. Stappaerts, William H. Steier, Gabriel G. Lombardi
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Patent number: 5202790Abstract: A photo-driven optical deflecting apparatus in which a light beam is deflected by using only light beam(s), comprising (a) a dielectric substrate having "photovoltaic effect"; (b) one or more first couples of electrodes formed in or on at least a portion of the surface(s) of said substrate so as to polarize the portion(s) positioned between said couple(s) of the electrodes formed thereby; (c) one or more photo-driving or photo-receiving elements provided at least in the polarized portion(s) of the surface of said dielectric substrate, having a polarization direction oriented in one direction, and having photovoltaic effect so as to generate a voltage between said electrodes; (d) a dielectric and transparent prism having "electrooptic effect" through which a light beam to be deflected is passed and deflected, provided on the surface of said substrate, having a second couple of electrodes provided on a couple of the surfaces of the prism, which surfaces are parallel to the optic axis; and a polarizer provided oType: GrantFiled: May 30, 1990Date of Patent: April 13, 1993Assignee: Mitsubishi Mining and Cement Company, Ltd.Inventors: Kenji Uchino, Kazuyasu Hikita, Yoshiaki Tanaka, Mikiya Ono
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Patent number: 5149953Abstract: Compensation for space charge build-up in an electro-optic modulator device is realized by recurrently recalibrating the device. During each recalibration interval, light transmitted through the device is intercepted and converted to an electric signal which is compared to a test signal of a magnitude corresponding to light of an intensity that would be transmitted through the device in the absence of space charge. The difference between the respective magnitudes of the test signal and the electric signal serves as a bias to supplement the normal modulating drive signal until the time of next recalibration. Recurrently, but at a rate lower than the recalibration rate, the device is short circuited, while flooded with light, to eliminate space charge build-up.Type: GrantFiled: December 24, 1990Date of Patent: September 22, 1992Assignee: Eastman Kodak CompanyInventor: James C. Erwin
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Patent number: 5121249Abstract: A multi-channel/multi-layer optical gate contained within a fiber-optic housing having any number of optical cells disposed within the housing. The optical cells are made up of non-linear organic polymers surrounded by a piezoelectric crystal, which is in turn connected to a photovoltaic device. When the photovoltaic device is activated, the piezoelectric crystals cause the non-linear organic polymers to change their refractive index, causing an interruption of a reference laser beam. An output detector is disposed within the fiber-optic housing for detecting the reference laser beam.Type: GrantFiled: April 11, 1990Date of Patent: June 9, 1992Inventor: William G. Fellows