Optical Change Type Patents (Class 250/474.1)
  • Patent number: 6437346
    Abstract: The present invention relates to an ultraviolet radiation detector in general and more specifically to a solar blind ultraviolet radiation detector; that is, a detector insensitive to the radiation of sunlight reaching the earth's surface but sensitive to UVC wavelengths in the spectrum, defined as the interval 200 nm-280 nm. The solar blind detector is base on the use of photochromic compounds in conjunction with ultraviolet wavelength-selective chemical blocks and their incorporation into optically clear polymer matrices. The photochromic compound is selected from the group comprising spiropyran molecules spirooxazine molecules and chromene derivatives. Applications for such device are as numerous as the sources of UVC radiation. An obvious use for such Solar Blind UVC detector is monitoring the output of UVC sources used in the decontamination of water and air (water treatment and air purification) and for sterilization of medical instruments.
    Type: Grant
    Filed: September 11, 2000
    Date of Patent: August 20, 2002
    Inventor: Kamal Goudjil
  • Patent number: 6433270
    Abstract: ORGANOMETALLIC COORDINATION complexes exhibiting two separate, stable forms are described. Conversion from one form to the other is intramolecular, reversible, light-activated (a molecular switch) and occurs both in the solid and in solution. The two forms differ in photochemical and electrochemical characteristics (different colors and reduction potentials). The complexes can be used in information storage and for light-gathering, light-emitting, sensing and detecting applications.
    Type: Grant
    Filed: September 25, 2000
    Date of Patent: August 13, 2002
    Assignee: California Institute of Technology
    Inventor: Jeffrey J. Rack
  • Publication number: 20020084423
    Abstract: A radiation dosimeter is described which utilizes the conversion of iodide by impinging ultraviolet or other equal or greater energy radiation in the presence of a thiosulfate moderating agent and the subsequent complexing of the iodine producing by a suitable starch to produce a color variation which is indicative of the amount of such radiation received.
    Type: Application
    Filed: January 4, 2001
    Publication date: July 4, 2002
    Inventor: Michael W. Ferralli
  • Publication number: 20020074514
    Abstract: The present invention is an article of manufacture for use in alerting a person of exposure to an excessive amount of ultraviolet radiation. In one embodiment, the article of manufacture comprises a first strip comprising a backing member and first and second patches. Each of the first and second patches comprise an ultraviolet sensitive material releasably disposed upon the backing member. Each of the first and second patches comprise first and second outside edges and an inside edge. The first and second patches are nested and adjoined along said inside edges of the first and second patches, respectively. The ultraviolet sensitive material is adapted to change from a first color to a second color when exposed to an excessive amount of ultraviolet radiation. In operation, a person may remove the first and second patches from the backing member as desired and apply the patch to an area of exposed skin.
    Type: Application
    Filed: December 18, 2000
    Publication date: June 20, 2002
    Inventor: Alan E. Nash
  • Patent number: 6406914
    Abstract: The present composition for use in radiation exposure dose-history indicators comprises a radioactive ray-absorber and/or a radioactive ray-excited fluorescence-emitting agent, a color-developing and electron-donating organic compound and an active species-generating organic compound, which can initiate the color development of the electron-donating organic compound through the application of radioactive rays. The indicator sheet for indicating the radiation exposure dose-history comprises a matrix sheet; and a color-developing layer, which contains a color-developing and electron-donating organic compound, an active species-generating organic compound, which can initiate the color development of the electron-donating organic compound through the application of radioactive rays, and a radioactive ray-absorber and/or a radioactive ray-excited fluorescence-emitting agent and which is applied to at least part of the surface of the matrix sheet.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: June 18, 2002
    Assignee: Nichiyu Giken Kogyo Co., Ltd.
    Inventors: Yoshiaki Kaburaki, Daisuke Harumoto, Hiromichi Mizusawa, Yukiyo Niwa, Hitoshi Shirase
  • Patent number: 6403962
    Abstract: A device for detecting X-radiation comprises a scintillator for converting X-radiation impinging thereon into light, a detecting device for detecting the light produced by the scintillator, and a fibre optic system for feeding the light produced by the scintillator to the detecting device. The device for detecting X-radiation is additionally provided with a heating means for heating at least one section of the fibre optic system to a predetermined temperature while the X-radiation is being detected.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: June 11, 2002
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V.
    Inventors: Peter Schmitt, Randolf Hanke, Norbert Bauer, Michael Maisl
  • Patent number: 6294792
    Abstract: The subject of the invention is a UV dosimeter suitable for visual evaluation, which is consisted of a light-sensitive layer on a carrier and a cover layer. The thickness of the light-sensitive layer is 10-40 &mgr;m, the concentration is 95-105 g/dm3 and calculated to the volume of the suspension it contains in a water bloated high molecular weight polymer amenable to hardening 0,004-0,2 mole/dm3 of argentic (I) oxalate, 0,0014-0,07 mole/dm3 of water soluble multivalent metallic oxalate and 0,00044-0,006 mole/dm3 of complexing additive. The light-sensitive layer is fitted with a cover layer, which is light-transmitting in the UVB range excluding the humidity of the air.
    Type: Grant
    Filed: May 3, 1999
    Date of Patent: September 25, 2001
    Assignee: Kossuth Lajos Tudomanyegyetem
    Inventors: György Bazsa, Mihály Beck, Zsolt Fazekas, Vincze Zsuzsanna Györgyné Fleischinger, Irén Horkay, Zoltán Nagy, Attila Nemes, István Országh, Miklós Rácz, Tibor Szalay
  • Publication number: 20010019110
    Abstract: A reusable dosimeter for sun radiation comprising a matrix with at least one active chemical compound distributed therein, capable of reversibly changing its original color to a new color due to a chemical reaction induced by exposure to UV radiation, said matrix made of a material having transparency sufficient for visual detection the change of the original compound's color to the new color, said active chemical compound being capable of changing its color after exposure to UV radiation with an efficacy corresponding to at least 1 MED, and reverting back to its original color after being kept in the dark for about 6 hours.
    Type: Application
    Filed: December 6, 2000
    Publication date: September 6, 2001
    Inventors: Ori Faran, Ezra Natan, Dmitry Lastochkin
  • Patent number: 6285031
    Abstract: A method and associated apparatus for monitoring exposure to radiation, with compensation for temperature variation of a sensor and variations in the amount of radiation sensitive material in a dosimeter used in the method. The method utilizes a radiation dosimeter having a layer of radiation sensitive material on a substrate, the radiation sensitive material having an optical absorbance which varies in accordance with degree of radiation exposure and wavelength and which also varies in dependence on temperature. The radiation sensitive layer includes a substantially radiation impervious substance.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: September 4, 2001
    Assignee: ISP Investments Inc.
    Inventors: Carl A. Listl, David F. Lewis
  • Patent number: 6268602
    Abstract: In a method for manufacturing a calibrated radiation dosimeter, a layer of radiation sensitive material is applied to a substrate, the radiation sensitive material having an optical density which varies in accordance with a degree of radiation exposure. A pre-exposure optical density of the layer of radiation sensitive material is optically measured and subsequently the layer of radiation sensitive material is exposed to a known dose of radiation. Thereafter, a post-exposure optical density of the layer of radiation sensitive material is optically measured. Using at least the pre-exposure optical density, the post-exposure optical density, and the known dose of radiation, one computes mathematical parameters defining a predetermined mathematical function. The computed mathematical parameters are applied in encoded form to the substrate (e.g., printed in bar code form on the substrate or a holder card).
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: July 31, 2001
    Assignee: ISP Investments Inc.
    Inventors: Henry Seiwatz, Carl A. Listl, J. Michael Donahue, David F. Lewis
  • Patent number: 6255659
    Abstract: A new class of ultraviolet dosimeters is made possible by exposing caged dye molecules, which generate a dye molecule on exposure to ultraviolet radiation, to an exterior environment. Applications include sunburn monitors, characterizing the UV exposure history of UV-sensitive materials, especially including structural plastics, and use in disposable ‘one-use’ optical equipment, especially medical devices.
    Type: Grant
    Filed: July 10, 1998
    Date of Patent: July 3, 2001
    Assignee: Sandia Corporation
    Inventor: David R. Sandison
  • Patent number: 6249004
    Abstract: The present invention is a composite material containing a mix of dosimeter material powder and a polymer powder wherein the polymer is transparent to the photons of wavelengths absorbed by the dosimeter material powder. The present method includes a method of interrogation that is substantially independent of dose rate and temperature. Interrogation is done with spectrophotometric measurements using ultraviolet or visible light.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: June 19, 2001
    Assignee: Sunna Systems Corp.
    Inventor: Steven Donald Miller
  • Patent number: 6232610
    Abstract: A dosimeter analysis system provides the capability to easily handle the radiochromic pieces of film which are commonly employed as dosimeters and make an accurate analysis of the amount of radiation received in an irradiation process. The dosimeter is constructed through use of one or more layers of a material such as paper, cardboard or non-woven material between which a piece of radiochromic film may be positioned. Through at least one of the layers, an aperture is formed which provides for the direct viewing of the radiochromic film. This dosimeter card may then be placed in a dosimeter card holder and placed in an analysis device such as a spectrophotometer. Also included on the dosimeter card may be a unique marking which provides a reference to unique information pertaining to the piece of radiochromic film employed in the dosimeter card.
    Type: Grant
    Filed: June 17, 1999
    Date of Patent: May 15, 2001
    Assignee: GEX Corporation
    Inventors: Gary M. Pageau, Steve Kruger
  • Patent number: 6218673
    Abstract: An optical scanner gives three dimensional dosimetric data by scanning, with at least one light beam, a translucent medium exhibiting optical properties which change upon receipt of radiant energy representing a dose distribution of the energy. At least one detector is employed to gather data indicative of changes in the optical properties of the medium after scanning from multiple directions to provide a representation of the optical properties in sections through the medium. Typical optical properties measured include optical density, light scattering, emitted light intensities, and combinations thereof.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: April 17, 2001
    Assignee: Yale University
    Inventors: John C. Gore, Marek J. Maryanski, Robert J. Schulz
  • Patent number: 6198108
    Abstract: A dosimeter device that is fabricated from a flat member separated into panels along fold lines. In an illustrated embodiment, a first panel has two attenuators thereon, a first attenuator formed of a first material and a second attenuator formed of a second material. The first panel also has a window or opening formed thereon. A second panel also has two attenuators thereon, a third attenuator formed of the same material as the first attenuator on the first panel and a fourth attenuator formed of the same material as the second attenuator on the first panel. The second panel is separated from the first panel by a fold line, and the second panel also has a window or opening formed thereon. A third panel is separated from the second panel by a second fold line, and has a radiation sensitive member thereon.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: March 6, 2001
    Assignee: Landauer, Inc.
    Inventors: David Schweitzer, Matthew Bantly, Robert Wheeler