Superimposed Or Series Patents (Class 359/890)
  • Patent number: 5953169
    Abstract: The present invention relates to a rotary drum type optical filter apparatus, which comprises a filter unit for receiving an optical signal to spectralize the optical signal; a lens unit provided at the center of the filter unit for varying an optical path of the optical signal; and a driving device engaged with the filter unit for providing a displacement of the filter unit relative to the lens unit to obtain different spectrum colors of the optical signal.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: September 14, 1999
    Assignee: Mustek System Inc.
    Inventor: Jenn-Tsair Tsai
  • Patent number: 5838508
    Abstract: A color filter comprising a substrate having thereon a layered structure comprising from the substrate side in this order, a color filter layer, a smoothing layer, a protective layer having a high reflectance and low absorptivity of laser beam, and a transparent electrically conductive layer. Also claimed is a process for fabricating the same and a color liquid crystal display device using the same.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: November 17, 1998
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Akira Sugawara
  • Patent number: 5795058
    Abstract: A transparency intended for use in a high intensity light beam projector for stage lighting purposes, comprises a glass substrate (10) having selected areas (11) thereof coated with a multi-layer dielectric coating forming a dichroic color filter. Selective coating is effected either by removing parts of an overall multi-layer coating through a mask, or by applying the multi-layer coating selectively through a mask.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: August 18, 1998
    Assignee: Light & Sound Design, Ltd.
    Inventor: Keith James Owen
  • Patent number: 5790329
    Abstract: A color changing device provides a continuously variable light color by means of the introduction of dichroic color filters into the light path of an illumination device. In the subtractive color mixing method for mixing of colors in an illumination apparatus according to the invention dichroic filters are provided parallel to each other and transverse to the beam path of the illumination apparatus, wherein the filters can be introduced into the beam path continuously and independently, so that a continuous mixing is achieved. At least four filters are used and wherein in view of the wavelength a broadband high-pass and a broadband low-pass, and two broadband band-stops are used, wherein the transmission regions of the two band-stops partly overlap so that with the filter combinations dominant colors with a high saturation can be generated.
    Type: Grant
    Filed: September 27, 1995
    Date of Patent: August 4, 1998
    Inventors: Welm Klaus, Feddersen-Clausen Oliver
  • Patent number: 5687263
    Abstract: A method for manufacturing an optical RF bandpass filter comprises the st of: (1) mounting an optical fiber having first and second ends in a fiber support structure having first and second surfaces so that the first end is exposed at the first surface and the second end is exposed at the second surface; (2) forming a first layered mirror structure on a first substrate to create a first mirror wafer structure having a first reflective surface; (3) forming a second layered mirror structure on a second substrate to create a second mirror wafer structure having a second reflective surface; (4) affixing the first reflective surface of the first mirror wafer structure to the first surface of the fiber support structure; and (5) affixing the second reflective surface of the second mirror wafer structure to the second surface of the fiber support structure.
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: November 11, 1997
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Shannon D. Kasa, Randy L. Shimabukuro, Wadad B. Dubbelday, Debra M. Gookin
  • Patent number: 5587847
    Abstract: The present invention is a laser protection window for protection from uncontrolled laser illumination. This laser protection window includes a holographic optical element forming a reflection hologram at the wavelength of the expected laser threat. A set of channel plates opaque to the expected laser threat wavelength are disposed at right angles to the holographic optical element in order to block laser illumination arriving outside the cone of protection of the holographic optical element. These channel plates may be vertically disposed to provide protection against mostly horizontally disposed laser threats. In alternative embodiments, the channel plates include both horizontally and vertically disposed plates or plates disposed in polygonal cross section to cover the entire area of the laser protection window.
    Type: Grant
    Filed: August 14, 1990
    Date of Patent: December 24, 1996
    Assignee: Kaiser Optical Systems
    Inventors: Byung J. Chang, James M. Tedesco
  • Patent number: 5543628
    Abstract: A controllable infrared filter (22) includes a quantum well filter unit (24) operable to absorb infrared energy at a selected wavelength. The quantum well filter unit (24) has a quantum well layer (26) made of an infrared transparent semiconductor mate rial and a barrier layer (28, 32) of another infrared transparent semiconductor material epitaxially deposited on each side of the quantum well layer (26). There is structure for controllably introducing charge carriers into the quantum well layer (26), which may utilize a source of electrons from other semi conductor layers (36, 38) and an applied voltage, or may utilize a laser (76) that generates charge carriers in the quantum well layer (26). The filter (22) further includes a lens (44, 46) or other optical system for directing infrared radiation through the first barrier layer (28), the quantum well layer (24), and the second barrier layer (32). Fixed band pass optical filters may be used in conjunction with the controllable quantum well filters.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: August 6, 1996
    Assignee: Hughes Aircraft Company
    Inventors: David H. Chow, Colin G. Whitney
  • Patent number: 5541735
    Abstract: A monocle can be provided with a light filter that transmits light wavelengths related to an animal's optical capabilities. The light filter will transmit light in the wavelengths and spectral sensitivity of the animal's retina rod photoreceptors, and in the wavelengths and spectral sensitivity of the animals retina cone photoreceptors during a specified light condition. The light filter selectively blocks certain wavelength ranges, such that the person using the monocle can effectively view objects in the same way as the animal does. The invention can be used to select clothing colors and patterns for camouflage purposes, select colored objects to be used in animal training, etc. A camera equipped with the desired light filter can also be used to aid in the selection process.
    Type: Grant
    Filed: March 10, 1995
    Date of Patent: July 30, 1996
    Inventor: Edward Rengle
  • Patent number: 5542010
    Abstract: A monolithically integrated wideband optical filter which is rapidly tunable to a large number of optical frequencies over a wide optical frequency range comprises two series connected optical filters of different resolutions formed in a semiconductive wafer. A control circuit applies electrical energy to predetermined controllably transmissive waveguides connecting components of the filters defined in the wafer. This tunes the overall filter to a desired one of a plurality of optical frequencies. Application of such electrical energy creates frequency selective pathways through the wafer able to pass one of up to hundreds of selected optical frequencies over the entire bandwidth of a semiconductive medium. This filter is economical to construct and is useful in high capacity, high speed optical communications networks.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: July 30, 1996
    Assignee: AT&T Corp.
    Inventors: Bernard Glance, Robert W. Wilson
  • Patent number: 5521759
    Abstract: An optical filter is provided for suppressing unwanted reflections of background light when used with a display device such as a cathode ray tube or an electroluminescent screen, or in optical communication or surveillance. The filter has multiple thin layers including a first series of layers for suppressing reflections from its outer surface and a second series of layers constituting a bandpass interference filter. The first series of layers is arranged to suppress reflections over a broad wavelength band while the second series of layers allows transmittance over a relatively narrow wavelength passband within the broad wavelength band, resulting in improved contrast when the display is used in situations of high background light.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: May 28, 1996
    Assignee: National Research Council of Canada
    Inventors: Jerzy A. Dobrowolski, Roger A. Kemp
  • Patent number: 5502595
    Abstract: A color filter comprising a transparent substrate and two or more multilayer films of amorphous silicon materials deposited on said substrate, each film being different, each layer of said two or more multi-layer films having a thickness less than the wavelength of the visible light and at least three layers of said two or more multi-layer films of amorphous silicon materials in an alternate arrangement wherein the amorphous silicon materials are selected from a-SiOx and a-SiNx is described. A method of preparing the color filter comprising depositing on the substrate by PECVD method two or more multilayer films is also described. The color filters prepared by PECVD method have a more compact texture and a better environmental resistant. The PECVD method for the preparation of the filters is more efficient than conventional methods.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: March 26, 1996
    Assignee: Industrial Technology Research Institute
    Inventors: Lee-Ching Kuo, Fang-Chuan Ho, William Lee, Yean-Kuen Fang
  • Patent number: 5481381
    Abstract: A color image reading apparatus comprises a plurality of line sensors which are a plurality of one-dimensional sensor arrays disposed on a single substrate, a projection optical system for projecting an image of a subject on the sensors, a blazed diffraction grating disposed in an optical path between the projection optical system and the sensors to separate light from the subject into a plurality of color lights, and a wavelength selection device disposed in an optical path between the subject and the sensors to permit only a beam of light within a specific wavelength range to pass therethrough.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: January 2, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventor: Makoto Fujimoto
  • Patent number: 5461516
    Abstract: A multilayer film structure includes a light absorption layer and a transparent layer so that a phase in the light absorption layer and a phase in the transparent layer have substantially constant values, irrespective of wavelengths of light transmitted through both the layers.
    Type: Grant
    Filed: September 9, 1993
    Date of Patent: October 24, 1995
    Assignee: Olympus Optical Co., Ltd
    Inventors: Yoshihiro Kawano, Takao Yamauchi, Yoshiaki Sano, Takashi Kasahara
  • Patent number: 5453883
    Abstract: An apparatus for producing a substantially monochromatic light beam for chromotherapy and/or actinotherapy is disclosed ; the apparatus comprises a transportable housing including a light source, which housing includes a movable heterogeneous interference filter mounted on a support that is displaceable by means of a motor, said apparatus further including a wand enabling said light beam to be directed onto a zone to be treated, and said apparatus also including transmission means for conveying said light beam from said housing to said wand, said housing including an infrared filter interposed between said light source and said interference filter.
    Type: Grant
    Filed: November 26, 1993
    Date of Patent: September 26, 1995
    Inventor: Frederic Chazallet
  • Patent number: 5426576
    Abstract: A color cross-fading system for a luminaire includes two filter disks or strips each provided with a multi-layer filter coating to provide a dichroic filter effect. In each case the thickness of the coating layers varies continuous along a gradient axis of the filter disk or strips. One disk acts predominantly as a long wave pass filter and the other act predominantly as a short wave pass filter, but each disk has an essentially "complex" characteristic enabling a very wide range of different colors to be obtained by cumulative subtractive filtering, by varying the positions of the two disks or strips relative to an optical axis.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: June 20, 1995
    Assignee: Light & Sound Design, Limited
    Inventor: William E. Hewlett
  • Patent number: 5399374
    Abstract: A color filter in accordance with the present invention comprises an activated film layer (2) arranged on a transparent substrate (1), said activated film layer (2) having a color pattern formed thereon by permeating a dye thereinto, and a thin metal film pattern (3) formed on a portion, of said activated film layer (2), which requires the formation of a black mask. Accordingly, the color filter integrated into various display devices such as a liquid crystal display is capable of displaying an image having a high contrast. Further, a method for forming a color filter in accordance with the present invention comprises the steps of forming an activated film layer (2) on a transparent substrate (1); permeating a dye into said activated film layer (2) to form a color pattern; and performing an electroless plating to form said thin metal film pattern (3) which functions as a black mask.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: March 21, 1995
    Assignee: Nissha Printing Co., Ltd.
    Inventors: Takao Sumi, Tenri Isoda, Yoshihide Inako, Masahiro Nishida
  • Patent number: 5325381
    Abstract: Multiple beam output scanning is obtained from a single raster scanning system (ROS) having a rotating mirror and a single set of scan optics. A plurality of coaxially overlapping laser beams from a common spatial location have either different polarization states or wavelengths. The swept beams are then separated by a plurality of optical beam splitters and absorption type optical polarizers and optical filters. The separated laser beams may be directed onto associated photoreceptors. The photoreceptors are beneficially located such that the optical path lengths from the laser beam sources to each photoreceptors are substantially the same.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: June 28, 1994
    Assignee: Xerox Corporation
    Inventor: Thomas L. Paoli
  • Patent number: 5317454
    Abstract: (S) A first optical material with a linear index of refraction is distributed as particles in a second optical material with an index of refraction dependent on the incident radiation intensity. Below some threshold intensity level the combination of materials is transparent to incident radiation directed toward a sensitive optical detector. Above this level, high-intensity incident radiation induces a change in refractive index of the second material, and the combination is limiting to incident radiation.
    Type: Grant
    Filed: August 30, 1984
    Date of Patent: May 31, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Edward J. Sharp, Gary L. Wood, Richard R. Shurtz, II
  • Patent number: 5301069
    Abstract: The present invention provides layered polymeric media to control the spatial and spectral distribution of energy in optical beams, particularly high intensity, broadband, multi-line laser beams. This structure is an improved version of prior art thin-film (vaccum deposited) interference filters and "rugate" structure filters.
    Type: Grant
    Filed: March 9, 1989
    Date of Patent: April 5, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Gary L. Wood, Wolfgang Elser, Edward J. Sharp
  • Patent number: 5270854
    Abstract: A solid state form of a dye-solution absorption filter is disclosed. Physical vapor depositable (i.e., evaporable) dyes are codeposited with a polyester matrix in a vacuum system to randomly disperse dye molecules in a solid dilutant. The dyes are selected to absorb at the wavelengths of interest. Dilution in a transparent matrix affords narrow band absorption and good out of band transmittance. Multilayer configurations allow absorption of a plurality of wavelengths. The filter coating conforms to curved and sharply contoured surfaces and layers only 10 microns thick afford very high absorptance.
    Type: Grant
    Filed: August 8, 1991
    Date of Patent: December 14, 1993
    Assignee: Honeywell Inc.
    Inventors: James C. Lee, David Greenlaw, Sau K. Lo
  • Patent number: 5262832
    Abstract: A color separation system for use in a color copying apparatus including blue, green and red reflection filters as well as blue and green transmission filters. The blue and green transmission filters are disposed in front of the blue and green reflection filters, respectively, so that light passes through the transmission filters twice. The color copying apparatus includes a photosensitive member which is exposed with light passing through the color separation system, an image sensor for reading an image of an color original, and a light adjusting filter for adjusting a quantity of light impinging on said image sensor. The three reflection filters and the light adjusting filter are mounted on a rotary member. One of these filters is selectively positionable in an optical path according to the rotated position of the rotary member.
    Type: Grant
    Filed: July 1, 1991
    Date of Patent: November 16, 1993
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventor: Katsuhiko Takeda
  • Patent number: 5262895
    Abstract: A color synthesizing device for generating a plurality of hues of color from visible light employing a beam splitter system to split the light into the three primary colors, mechanical attenuators to independently attenuate the primary color and light beams, and a recombination system to recombine the light beams to obtain the desired color hue of light.
    Type: Grant
    Filed: November 19, 1991
    Date of Patent: November 16, 1993
    Inventors: Thomas F. LaDuke, Joel D. Gruber
  • Patent number: 5214725
    Abstract: An optical coupler/splitter having an optical waveguide on the side of light incidence, two optical waveguides on the branched side, branched from the former optical waveguide and each having straight and curved sections, and a dielectric multi-layer film filter provided in a manner crossing the latter waveguides and common to them. The filter is so formed as to intersect with a straight section of one waveguide and with a curved section of the other, so that respective crossing angles between the filter and the branched optical waveguides differ from each other, thereby providing different reflection or transmission characteristics with respect to the branched optical waveguides. An optical signal having a variable wavelength and issued from a measuring apparatus based on the backscattering method is distinguished by the common filter of the coupler/splitter, making it possible to perform measurement of the losses of the branched optical waveguides independently without being affected by interference light.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: May 25, 1993
    Assignee: The Furukawa Electric Co., Ltd.
    Inventors: Hisaharu Yanagawa, Takeo Shimizu, Shiro Nakamura, Isao Ohyama
  • Patent number: 5214494
    Abstract: A light sensor comprises optical filters, an interference filter and a photoelectric converting element which receives and photoelectrically converts light which has passed through the optical filters and the interference filter. An incident angle of the incident light on the interference filter can be changed so as to realize a desirable spectral sensitivity in a combination of the optical filters, the interference filter and the photoelectric converting element. The incident angle can be changed by a mounting structure that can rotate about an optical axis.
    Type: Grant
    Filed: September 4, 1991
    Date of Patent: May 25, 1993
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masahito Inaba, Masami Sugiyama
  • Patent number: 5208698
    Abstract: An optical device that is optically neutral to normal light but absorbs highly collimated light is formed as a mosaic of optical cells. Each cell has at least two refracting surfaces and a non linear material at a focus internal to those surfaces. In one form, the cell comprises two pairs of lenses with a layer of non-linear light absorbent material interposed between the lenses of each pair. The lens elements can be one-power telescopes. A first lens element focuses highly collimated light at its entrance aperture on the non-linear layer. The intensity of the focused light causes the non-linear layer to become opaque or reflective and thereby reduce, or substantially block, the transmission of highly collimated light. The second pair of lenses inverts the re-collimated light exiting the first lens pair.
    Type: Grant
    Filed: December 19, 1990
    Date of Patent: May 4, 1993
    Assignee: The Mitre Corporation
    Inventor: Richard A. Muller
  • Patent number: 5182788
    Abstract: An optical bandpass filter comprises a waveguide region for guiding an optical beam from an input end to an output end, a clad structure provided above and below the waveguide region for confining the optical beam therein, a plurality of quantum well boxes formed in the waveguide region with respectively different quantum levels for selectively absorbing an optical component in the incident optical beam that causes a resonant absorption with the quantum level of the quantum well box, a barrier region provided in the waveguide region for surrounding each of the plurality of quantum well boxes with respect to all of three-dimensional directions and comprising a material having a second band gap that is substantially larger than said first band gap, and window means provided on the clad structure for directing a control optical beam such that the control optical beam irradiates the plurality of quantum well boxes.
    Type: Grant
    Filed: March 19, 1992
    Date of Patent: January 26, 1993
    Assignee: Fujitsu Limited
    Inventor: Kazuhiro Tanaka
  • Patent number: 5173811
    Abstract: An optical shield which is transparent to ambient light but which blocks high intensity light such as that from a laser, with a response speed on the order of several picoseconds or less, to provide eye protection and to protect light sensors from laser beams. The shield is a multilayer structure with layers in which colloidal silica particles are dispersed in a transparent polymer binder having an index of refraction close to that of the silica particles under ambient light conditions. The application of multiple sealant layers of pure binder material results in improved transmittance of ambient light. High intensity light such as that from a laser causes third order nonlinear optical effects, particularly photorefractive effects, in the silica which change its effective index of refraction so that the mismatch between the effective index of refraction of the silica and the index of refraction of the binder causes scattering of the incident light.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: December 22, 1992
    Assignee: Gumbs Associates, Inc.
    Inventor: Ronald W. Gumbs
  • Patent number: 5151829
    Abstract: A kinetic art article assembly with stacked color filter comprises a base, two support plates, a cylindrical main body with a front main body and a rear main body, a fluid governor, and a drive mechanism. At least a set of plate assembly is disposed in the front main body and the rear main body. The plate assembly has a front plate, a flat plate and a rear plate. Each of the flat plate and the rear plate has a tube thereon so that liquid in the tube can flow in to the recesses of the front plate or the rear plate.
    Type: Grant
    Filed: June 24, 1991
    Date of Patent: September 29, 1992
    Inventor: Ren-Yi Hwang
  • Patent number: 5149182
    Abstract: An improved optical filter for use in an optical measurement instrument has a corrective optical glass filter with a negative deviation in the range of 470 nm added to the optical filter to offset a positive deviation in the range of 470 nm in an amber or blue glass filter used in the optical filter. The improved optical filter in interposed between a photoelectric element in the optical measurement instrument and the source of electromagnetic radiation. The photoelectric device converts the electromagnetic radiation to an electrical signal which is processed and displayed. In one embodiment of the invention the optical filter has a spectral response matching that of the average human eye and in a further embodiment the optical filter has an approximate equal response over a spectral range from ultraviolet to infrared.
    Type: Grant
    Filed: May 2, 1991
    Date of Patent: September 22, 1992
    Assignee: Tektronix, Inc.
    Inventor: Peter A. Keller
  • Patent number: 5144498
    Abstract: Light filter apparatus for receiving a light beam having wavelengths in a selected band and for dispersing the light into a plurality of rays, with each ray having a different wavelength for which the intensity peaks. The peak wavelength varies approximately continuously with displacement of spatial position in a chosen direction along the filter's light-receiving plane. In one embodiment, the filter is a modified etalon structure having at least two reflecting surfaces whose separation distance is not constant but increases or decreases monotonically with distance in a chosen direction in a light-receiving plane of the etalon. Each of these two reflecting surfaces may be planar or non-planar but continuous, or may have a step or staircase configuration. This structure may operate using transmitted light or reflected light.
    Type: Grant
    Filed: February 14, 1990
    Date of Patent: September 1, 1992
    Assignee: Hewlett-Packard Company
    Inventor: Kent D. Vincent
  • Patent number: 5126886
    Abstract: A color changer (20) comprising a component hue saturation filter (30) including an elongated flexible substrate (32) having a surface with a gradient axis (GA) and which includes a graded portion (G) supporting a uniform concentration of a selected hue filtering material (50) distributed in a continuously graded average density in beam-size areas around points along the gradient axis. The component hue saturation filters may be embodied in separate substrates positionable in parallel planes to be intersected serially by a beam of light. Alternately, dual-hue filters (68) may be formed by two primary hue component filters embodied in respective substrates each also embodying duplicate third primary hue component filters producing the same effects. Saturations of each selected hue of light appear evenly distributed in the output beam without the need for color components to be further commingled.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: June 30, 1992
    Assignee: Morpheus Lights, Inc.
    Inventors: Brian E. Richardson, John R. Richardson
  • Patent number: 5115379
    Abstract: A composite filter advantageously employable for dark field observation systems which comprises a dyed organic resin layer provided on a dyed glass plate. The organic resin layer and the glass plate in combination absorb light of a radiation spectrum in the region of longer than 600 nm under the condition that the transmission of light at 650 nm is defined to a level of 1.times.10.sup.-4 % to 5% and the transmission of light at 800 nm is defined to a level of lower than 2.times.10.sup.-5 %. Another dyed glass plate which shows an absorption spectrum having absorption peaks in regions of 480-535 nm and 560-600 nm may be incorporated into the composite filter. The composite filter can be introduced into or provided to an illuminating device.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: May 19, 1992
    Inventor: Kiyoshi Nagai
  • Patent number: 5107529
    Abstract: A radiographic equalization apparatus comprises a plurality of juxtaposed disks each having a plurality of unique filtration patterns annularly disposed therearound. The disks are rotated relative to one another to obtain a unique attenuation pattern for correcting for overexposures in an x-ray image.
    Type: Grant
    Filed: October 3, 1990
    Date of Patent: April 21, 1992
    Assignee: Thomas Jefferson University
    Inventor: John M. Boone
  • Patent number: 5102213
    Abstract: A solid state form of a dye-solution absorption filter is disclosed. Physical vapor depositable (i.e., evaporable) dyes are codeposited with a polyester matrix in a vacuum system to randomly disperse dye molecules in a solid dilutant. The dyes are selected to absorb at the wavelengths of interest. Dilution in a transparent matrix affords narrow band absorption and good out of band transmittance. Multilayer configurations allow absorption of a plurality of wavelengths. The filter coating conforms to curved and sharply contoured surfaces and layers only 10 microns thick afford very high absorptance.
    Type: Grant
    Filed: February 28, 1990
    Date of Patent: April 7, 1992
    Assignee: Honeywell Inc.
    Inventors: James C. Lee, David Greenlaw, Sau K. Lo
  • Patent number: 5082337
    Abstract: A filter device 10 and method of making the same is disclosed. The device comprises holographic means 12 for diffracting optical radiation of a first predetermined range of wavelengths, and optical radiation filter means 14 for filtering optical radiation of a second predetermined range of wavelengths. The optical radiation filter means is coupled with the holographic means.
    Type: Grant
    Filed: December 16, 1988
    Date of Patent: January 21, 1992
    Assignee: Hughes Aircraft Company
    Inventors: Mao-Jin Chern, John E. Wreede
  • Patent number: 5071227
    Abstract: An optical filter is formed as a rectangular parallelepiped having a plurality of beveled edges formed thereon, preferably three non-intersecting beveled edges formed at an angle of 45 degrees. The filter is formed of a clear, transparent, durable, shock-resistant material, preferably abrasion-resistant Lucite.TM. acrylic resin (trademark of the Du Pont Corporation) impregnated with a subtractive dye. The material has a refractive index closely matching that of glass, but is tougher and more shock resistant. The filter dimensions are in the ratio of small whole integers, specifically 2:3:4, for example, 1.times.1.5.times.2 inches. The beveled edges increase the residence time of light within the filter. By positioning differently colored filters of different orientations in optical series, many different hues may be produced.
    Type: Grant
    Filed: December 7, 1990
    Date of Patent: December 10, 1991
    Assignee: Luminati Ltd., Inc.
    Inventor: David A. Dowd
  • Patent number: 5044730
    Abstract: The present invention is a device for generating a plurality of colors of light from a light source. The device includes a plurality of filters to separate the light at predetermined wavelengths and to recombine them at different amplitudes to generate a predetermined color hue in the visible spectrum of light.
    Type: Grant
    Filed: February 8, 1989
    Date of Patent: September 3, 1991
    Assignee: Artifex Corporation
    Inventors: Thomas F. LaDuke, Joel D. Gruber, Richard Romano
  • Patent number: 5037180
    Abstract: In this invention there is disclosed an optical filter disposed on an optical fiber. More specifically, a filter comprised of a multilayer thin-film stack of low and high index of refraction material is deposited onto the end of an optical fiber. The filter can be, for example, a long-pass filter, a Fabry-Perot Etalon, a Double-Cavity Filter, and the like. Filters deposited on perpendicular facets of single-mode fibers reflect most of the power that is not transmitted. This reflection if fed back to a laser or an amplifier can cause a problem, particularly if an isolator does not adequately block the reflections. A bevel on the fiber end face can eliminate this problem by preventing the reflected power from being directed back into the optical fiber.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: August 6, 1991
    Assignee: AT&T Bell Laboratories
    Inventor: Julian Stone
  • Patent number: H1154
    Abstract: A Blue-Green spectral Filter and two polaroid filters are assembled within rotating barrel assembly to both limit light source emissions to a selected light spectrum and control light intensity in order to prevent enemy night vision device detection. The rotating barrel assembly can be manufactured to attach to any type of light source. In addition, environmental protection from rain and dust is maintained through O-ring seals.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: March 2, 1993
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: David J. Gibson, Paul F. Rohrbacher