Light Interference Patents (Class 359/577)
  • Patent number: 5612778
    Abstract: An optical device and method for sensing a plurality of ambient conditions (e.g., temperature and pressure) may include transmission of an optical flux through a fiber optic cable to a section of the cable that is placed where the ambient conditions are to be sensed. The section of cable includes a plurality of serially aligned sensors for reflecting the optical flux back through the cable, each of the sensors having semi-reflective surfaces at the two ends thereof for partially reflecting the optical flux. The distance between the two ends of each sensor varies primarily as a function of a different one of the ambient conditions. The optical flux is partially transmitted and partially reflected at each of the ends of the sensors and the optical flux reflected back through the cable includes an interference pattern that is a function of each sensor's end-to-end distance. A detector evaluates the interference pattern to determine the ambient conditions.
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: March 18, 1997
    Assignee: Harris Corp.
    Inventors: Christopher J. Hall, Calvin L. Adkins, David Graves, Ed Bryant
  • Patent number: 5587834
    Abstract: A semiconductor device manufacturing method is disclosed, which includes the steps of illuminating obliquely an original having a grating-like pattern, with a light beam having a main wavelength .lambda., and projecting a portion of diffraction light produced by the pattern onto a pupil plane of a projection optical system having a numerical aperture NA, so as to project the pattern onto a predetermined plane related to a photosensitive substrate, wherein the original has a partially isolated pattern and an auxiliary pattern, the partially isolated pattern is such a pattern having no adjoining pattern within a range of D.ltoreq.(.lambda./NA) where D is the distance from one side thereof as measured on the predetermined plane, the auxiliary pattern has a linewidth L which satisfies the relation L.ltoreq.0.2(.lambda.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: December 24, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventor: Miyoko Noguchi
  • Patent number: 5583689
    Abstract: A filter has a preselected attenuation/wavelength characteristic, in which spatially separated parts of the filter attenuate different wavelengths. The spatially-separated parts have different attenuation characteristics to attenuate different wavelengths in a predetermined manner to provide a selected attenuation/wavelength characteristic. In one arrangement an interference type filter includes a grating, the pitch of which varies spatially. In one instance, the structure to determine the proportion of radiation subject to interference includes a grating of spatially-varying effectiveness, but alternatively it may include an attenuation filter, the attenuation effect of the attenuation layer varying spatially. In another arrangement, the filter may include structure to separate received radiation into a spatially-disposed spectrum, and to attenuate different parts of the spatially-disposed spectrum in such a manner as to provide the selected attenuation/wavelength characteristic.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: December 10, 1996
    Assignee: British Telecommunications public limited company
    Inventors: Stephen Cassidy, Richard Wyatt, Raman Kashyap, Jonathan R. Armitage, Robert Campbell
  • Patent number: 5574473
    Abstract: An image display apparatus comprises an image display unit capable of generating and displaying a plurality of coherent point light source pairs, a light transmission unit for focusing the point light source pairs on the pupil plane of an observer's eye so that an image is formed on the retina of the eye by the effect of optical interference, a visual axis detector for monitoring the movements of the eye and detecting the visual axis direction thereof, and an image display correcting unit for restricting a distortion of the image, caused by the eye movements, within its tolerance in accordance with data detected by the visual axis detector. The image display correcting unit includes an optical member set in an optical path between the image display unit and a lens, and an optical member drive unit for tilting the optical member for a given angle in a predetermined direction.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: November 12, 1996
    Assignee: Olympus Optical Co., Ltd.
    Inventor: Nobutoshi Sekiguchi
  • Patent number: 5555126
    Abstract: A means, method and apparatus for dual-phase amplification of wave-type signals is disclosed comprising superimposing a constant level beam set and a modulated beam set to produce a first interference image at first and second locations. A first image component separator separates energy from constructive and destructive interference component regions to produce secondary beam sets that are combined to produce a second interference image, which is separated at a destructive interference region to produce the output. The amplifier with multiple inputs is then connected in cascade, as a phase-bistable device, as a level detector, an AND, an OR, and/or a synchronized oscillator. Multiple frequencies work independently, allowing for frequency-multiplexed functions.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: September 10, 1996
    Inventor: John N. Hait
  • Patent number: 5545561
    Abstract: The contrast chamber for spotlighting bacterial colonies with respecto to their culture medium performs the automatic counting, through the use of an automatic processor connected to a reading head (7), of bacterial colonies which develop in the capsules wherein the culture takes place; additionally, it also provides for the automatic introduction of the capsules (5) inside the contrast chamber The contrast chamber is provided with lateral lighting means, using the light reflected by a reflection tube (2) and emitted by a lighting source (1) postioned above the capsule (5) which has been closed by a lid provided with an opaque disc (3). The reading head (7) is positioned under the capsule (5) and is associated to a second light source (8) which moves together with the reading head and which is inclined with respect to the surface of the capsule (5), so that the light beams do not impinge on the reading head (7).
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: August 13, 1996
    Assignee: IUL, S.A.
    Inventor: Miguel Lleonart Aliberas
  • Patent number: 5532062
    Abstract: A low emissivity film comprises a coating of an oxide film, a metal film, an oxide film and so on alternately formed on a substrate in this order in a total of (2n+1) layers where n is an integer being equal to or more than 1, wherein an oxide film (B) formed on the side opposite to a metal film (A) being most remote from the substrate in view from the substrate, contains at least one layer of a zinc oxide film doped with at least one selected from the group consisted of Si, Ti, Cr, B, Mg, Sn and Ga by 1 through 10 atomic % with respect to a total amount including Zn.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: July 2, 1996
    Assignee: Asahi Glass Company Ltd.
    Inventors: Masami Miyazaki, Eiichi Ando
  • Patent number: 5446589
    Abstract: An interference device and method for observing phase information, using electron or other waves with the amplitude difficult to split by a half mirror.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: August 29, 1995
    Assignees: Research Development Corporation of Japan, Junji Endo, Akira Tonomura
    Inventors: Qing X. Ru, Junji Endo, Akira Tonomura
  • Patent number: 5419969
    Abstract: A low emissivity film formed on a substrate, which comprises a coating of oxide films and films whose major component is Ag alternately formed on the substrate in a total of (2n+1) layers where n is an integer being equal to or more than 1, with the innermost layer being an oxide film, wherein an integral width .beta.i(.degree.) of (111) diffraction line of a cubic Ag in an X-ray diffraction diagram of the low emissivity film exists in a first range of 180.lambda./(d.pi.cos.theta.).ltoreq..beta.i.ltoreq.180.pi./(d.pi.cos.thet a.)+0.15, where d(.ANG.) designates a thickness of a film whose major component is Ag, .pi.(.ANG.), a wave length of an X-ray for measurement and .theta., Bragg angle.
    Type: Grant
    Filed: November 27, 1991
    Date of Patent: May 30, 1995
    Assignee: Asahi Glass Company Ltd.
    Inventors: Masami Miyazaki, Eiichi Ando
  • Patent number: 5418641
    Abstract: Resonant cavity apparatus comprise a Fabry-Perot optical resonant cavity of a type having families of transverse modes between longitudinal TEM.sub.00 modes. In such resonant cavity apparatus and in methods of minimizing the effect of transverse modes, families of such transverse modes are merged into longitudinal TEM.sub.00 modes of the non-confocal Fabry-Perot optical resonant cavity, providing superior optical performance. This may be manifested by a transmission spectrum similar to that of a flat-flat Fabry-Perot cavity, but with superior Finesse and transmission efficiency.
    Type: Grant
    Filed: October 25, 1993
    Date of Patent: May 23, 1995
    Assignee: Newport Corporation
    Inventors: Sami T. Hendow, Thomas J. Kujawa
  • Patent number: 5418136
    Abstract: Optical assay device having an active receptive surface supported on a pedestal and held within a first container; the first container comprising first absorbent material located at the base of the pedestal, configured and arranged to absorb liquid draining from the surface, and having a second container, hingedly connected to one side of the first container, the second container comprising a second absorbent material, wherein the second container can be closed to the first container by rotation about the hinge, and wherein such closing causes the second absorbent material to contact the surface.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: May 23, 1995
    Assignee: Biostar, Inc.
    Inventors: B. John Miller, Diana M. Maul, James Blessing, Mark Crosby, Howard Kelley
  • Patent number: 5413864
    Abstract: A low emissivity film which comprises: a substrate; and a coating of oxide and metallic films alternately formed on the substrate in a total of (2n+1) layers where n is an integer being equal to or more than 1, with the innermost layer being an oxide film, wherein the oxide film (B) formed on the outer side of the metallic film (A) being most apart from the substrate, has an internal stress which is equal to, or less than 1.1.times.10.sup.10 dyne/cm.sup.2.
    Type: Grant
    Filed: July 5, 1991
    Date of Patent: May 9, 1995
    Assignee: Asahi Glass Company Ltd.
    Inventors: Masami Miyazaki, Eiichi Ando
  • Patent number: 5392156
    Abstract: An optical device is composed of: a transparent base plate formed of a glass or a macromolecular resin; a first layer formed of a substance having a refractive index of 1.58 or higher; and a second layer formed of an amorphous transparent fluorocarbon resin having a refractive index of 1.35 or lower. The second layer is farther from the transparent base plate than the first layer from the transparent base plate. The first and second layer constitute a film for preventing reflection. Optionally, adhesive layers are provided between the transparent base plate and the first layer and between the first layer and the second layer. Further optionally, the surfaces of the transparent base plate and the first layer are treated in order to enhance adhesion between the contact surfaces.
    Type: Grant
    Filed: March 22, 1993
    Date of Patent: February 21, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroaki Kumagai, Nagato Osano, Naoki Kobayashi
  • Patent number: 5390046
    Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering and for signal processing applications. The systems utilize an interferometer configuration. A first optical modulator in a first leg of the interferometer is used to modulate coherent light with the signal to be delayed. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a stack of lens pairs or diffractive optical elements or a holographic optic element may be used in place of the prism stack. The modulated optical signal from the first leg interferes on an array of photodiodes with the reference waves from the second leg.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: February 14, 1995
    Assignee: Essex Corporation
    Inventors: Leslie H. Gesell, Terry M. Turpin
  • Patent number: 5291330
    Abstract: A system for enhancing the resolution of an image comprising a plurality of phase affecting light transmitting objects, preferably plates, disposed in a stack in the light path of the light energy defining an image, each plate having a thickness and being spaced a distance apart from others of the plates. Preferably, a source of radiant energy is provided for irradiating the plates and spaces between the plates in the stack and optionally the image itself to enhance resolution further by creating standing waves that interfere with the light in the light path defining the image. The plates are preferably edge illuminated, and the radiant energy may be visible light, ultraviolet energy or infrared energy, individually or intermixed. The system has application both for enhancing existing images as well as enhancing images during the image storage process.
    Type: Grant
    Filed: November 3, 1989
    Date of Patent: March 1, 1994
    Inventor: Joseph Daniels
  • Patent number: 5289314
    Abstract: This invention provides embodiments of etalons (10, 14, 18, 22) that eliminate or minimize a falloff of relative radiation modulation as a function of wavelength or FOV. A first embodiment employs a dispersive coating, such as a rugate (12a, 12b, 16), to correct for the phase shift across an etalon step. A second embodiment employs a dispersive coating, such as a rugate (20a, 20b, 24), that provides a stepless etalon in which the phase shifts are generated by the coating. It is shown that in a rugate the phase shift on reflection is directly related to the phase of a sinusoidal index of refraction profile within the rugate, while the frequency of the sinusoidal index of refraction profile determines the wavelength at which the phase shift occurs. By changing the phase of the sinusoidal index of refraction variation as the period of the sinusoidal index of refraction variation is changed, a phase shift of incident radiation is produced that is a function of the wavelength of the incident radiation.
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: February 22, 1994
    Assignee: Hughes Aircraft Company
    Inventor: Edward T. Siebert
  • Patent number: 5253110
    Abstract: An illumination optical arrangement which uses a laser light source to produce a uniform illumination which is high in brightness and substantially free of interference patterns. The illumination optical arrangement includes light source means for emitting a coherent light beam, optical illuminance distribution uniformizing means for making substantially uniform the intensity distribution in a beam cross-section of illumination by the coherent light beam on a plane to be illuminated, and optical polarizing means for producing from the coherent light beam a plurality of polarized light components which are different in polarized state from each other in such a manner that wavefronts of incident light beams of the polarized light components to the optical illuminance distribution uniformizing means are inclined relative to each other whereby interference patterns produced by the polarized light components are relatively shifted in position in the illuminated plane.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: October 12, 1993
    Assignee: Nikon Corporation
    Inventors: Yutaka Ichihara, Yuji Kudo
  • Patent number: 5245473
    Abstract: An apparatus and method for laser velocity interferometry employing a fixed interferometer cavity and delay element. The invention permits rapid construction of interferometers that may be operated by those non-skilled in the art, that have high image quality with no drift or loss of contrast, and that have long-term stability even without shock isolation of the cavity.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: September 14, 1993
    Assignee: Sandia Corporation
    Inventors: Philip L. Stanton, William C. Sweatt, O. B. Crump, Jr., Lloyd L. Bonzon
  • Patent number: 5238785
    Abstract: A method for manufacturing a diffraction grating includes applying a resist, the developing speed of which has an extreme at a certain exposure intensity, to a substrate on which the diffraction grating is to be formed, performing interference exposure of the resist with maximum and minimum values of exposure intensity respectively larger and smaller than the intensity which makes the developing speed an extreme, developing the resist, and etching the substrate using the remaining resist as a mask.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: August 24, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuji Ohkura, Masatoshi Fujiwara
  • Patent number: 5202776
    Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering. The systems utilize an interferometer configuration. A first optical modulator and a Fourier transform lens define a Fourier transform plane in a first leg of the interferometer. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a holographic optic element could be used in place of the prism stack.
    Type: Grant
    Filed: December 12, 1991
    Date of Patent: April 13, 1993
    Assignee: Essex Corporation
    Inventors: Leslie H. Gesell, James L. Lafuse
  • Patent number: 5161045
    Abstract: Coherent light from a laser is directed through first and second two dimensional planar arrays of lenslets which are moved relative to each other to enable the beam to point along any diffraction order, and fine pointing of the beam between orders is accomplished by slightly changing the angle of incidence of the beam with respect to the arrays. The laser is replaced by a photoreceptor when the scanner operates as a light beam receiver.
    Type: Grant
    Filed: June 28, 1990
    Date of Patent: November 3, 1992
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Richard A. Hutchin
  • Patent number: 5108168
    Abstract: A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employes speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds.
    Type: Grant
    Filed: May 16, 1990
    Date of Patent: April 28, 1992
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Norbert. Massie A., Yale, Oster
  • Patent number: 5093802
    Abstract: A fundamental method and apparatus for using wave-type energy, such as light, to provide: amplification, energy control, and logic functions including OR, EXCLUSIVE OR, and INVERTER; as well as: bistable information storage; computing; visual display; and dynamic imaging (where images are modified continually as computation proceeds) is disclosed. The method uses modulated input beams that are able to produce interference fringes, that are separated into constructive interference component regions and destructive interference component regions, to provide outputs from individual functions, that result from the interference which occurs in the separated interference-fringe component regions. Many basic functions are interconnected to produce more complex functions including complete digital and analog computers. Holograms made up of many subholograms are used to separate fringe component regions, and to direct function interconnecting beams.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: March 3, 1992
    Assignee: Rocky Mountain Research Center
    Inventor: John N. Hait
  • Patent number: 5080466
    Abstract: In a Michelson inteferometer with phase conjugate mirrors at least one of such mirrors includes a Kerr medium. This enables control over the relative phases of the beams that are reflected from the mirrors and superimposed to form an output beam. The interferometer can be used to perform a logic function by interposing transparencies in the reflected beams. By appropriate choice of the relative phases a logic OR function can be achieved.
    Type: Grant
    Filed: March 8, 1990
    Date of Patent: January 14, 1992
    Assignee: National Research Council Canada
    Inventors: Simon A. Boothroyd, Jacek Chrostowski
  • Patent number: 5058973
    Abstract: A reading device operates by the placing in interference of a reference signal, in the form of a fundamental wave train, with delayed wave trains constituting the useful signal. The device comprises an interferometer, a first branch (32) of which is traversed by at least said fundamental wave train (14), the first branch (32) being equipped, with means (37, 67, 87) for the generation of quantified delays of said fundamental wave train (14) with means (39) for the generation of a continuously variable delay of said fundamental wave train (14) over a range about each quantified delay value.
    Type: Grant
    Filed: February 27, 1990
    Date of Patent: October 22, 1991
    Assignee: Thomson-CSF
    Inventors: Philippe Refregier, Dominique Rojas, Marc Turpin
  • Patent number: 5056099
    Abstract: The rugate filter comprises a glass film which is deposited on one or both end facets of a diode laser. The glass film has a continuously varying refractive index with thickness, usually in the form of a sine wave or a "windowed" sine wave. Such a film may be deposited by ion-assisted co-deposition techniques in which the concentration of the higher refractive index material is periodically varied according to the period required to produce the desired filter. The glass of which the rugate filter is formed has an average refractive index which does not vary with temperature by more than 10.sup.-6 /.degree.C. By reflecting light at the peak wavelength back into the laser, the laser is caused to emit at the desired wavelength. Since the rugate filter selectively reflects light within a narrow band of the desired wavelength, the laser emits light within a narrow peak on the order of 10 .ANG. or less.
    Type: Grant
    Filed: September 10, 1990
    Date of Patent: October 8, 1991
    Assignee: General Dynamics Corp., Electronics Division
    Inventor: Eric M. Bradley