Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS20050136200 A1
Publication typeApplication
Application numberUS 10/742,552
Publication dateJun 23, 2005
Filing dateDec 19, 2003
Priority dateDec 19, 2003
Publication number10742552, 742552, US 2005/0136200 A1, US 2005/136200 A1, US 20050136200 A1, US 20050136200A1, US 2005136200 A1, US 2005136200A1, US-A1-20050136200, US-A1-2005136200, US2005/0136200A1, US2005/136200A1, US20050136200 A1, US20050136200A1, US2005136200 A1, US2005136200A1
InventorsChristopher Durell, Wolfgang Bohme
Original AssigneeDurell Christopher N., Wolfgang Bohme
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Diffuse high reflectance film
US 20050136200 A1
Abstract
A diffuse reflective film including a bottom layer of reflective specular material and a top layer of polytetrafluoroethylene (PTFE) diffuser material for diffusely reflecting at least 96% of light in the portion of the electromagnetic spectrum between about 400 nanometers and about 2500 nanometers, and wherein the diffuse reflective film has a thickness of less than 1500 micrometers.
Images(4)
Previous page
Next page
Claims(24)
1. A diffuse reflective film including a bottom layer of reflective specular material and a top layer of polytetrafluoroethylene (PTFE) diffuser material for diffusely reflecting at least 96% of light within a portion of the electromagnetic spectrum between about 400 nanometers and about 2500 nanometers, and wherein the diffuse reflective film has a thickness of less than 1500 micrometers.
2. A diffuse reflective film according to claim 1, wherein the top layer of PTFE diffuser material comprises Zenith™ PTFE-based diffuse reflectance film.
3. A diffuse reflective film according to claim 1, wherein the bottom layer of reflective specular material comprises thermally induced phase separation (TPIS) layered polymer film.
4. A diffuse reflective film according to claim 1, wherein the top layer of PTFE diffuser material has a thickness of not more than 1000 micrometers.
5. A diffuse reflective film according to claim 1, wherein the bottom layer of reflective specular material has a thickness of not more than 500 micrometers.
6. A diffuse reflective film according to claim 1, wherein an adhesive layer is provided between the top layer of PTFE diffuser material and the bottom layer of reflective specular material.
7. A diffuse reflective film according to claim 1, wherein an adhesive layer is provided on a bottom surface of the bottom layer of reflective specular material.
8. A diffuse reflective film according to claim 1, wherein one of a top and bottom surface of the bottom layer of reflective specular material is more reflective and the top layer of PTFE diffuser material is placed on the more reflective surface.
9. A light conduit including a diffuse reflective film according to claim 1, and further comprising an outer shell and, wherein the diffuse reflective film covers at least a portion of an inner surface of the outer shell.
10. A light box including a diffuse reflective film according to claim 1, and further comprising an outer shell and, wherein the diffuse reflective film covers at least a portion of an inner surface of the outer shell.
11. A liquid crystal display including a diffuse reflective film according to claim 1, and further comprising a light guide directing light from a light source, wherein the diffuse reflective film covers at least a portion of an inner surface of the light guide.
12. A light emitting diode display including a diffuse reflective film according to claim 1, and further comprising a light guide directing light from a light source, wherein the diffuse reflective film covers at least a portion of an inner surface of the light guide.
13. An optical cavity including a diffuse reflective film according to claim 1, and further comprising a light guide directing light from a light source, wherein the diffuse reflective film covers at least a portion of an inner surface of the light guide.
14. A sign cabinet including a diffuse reflective film according to claim 1, and further comprising walls directing light from a light source, wherein the diffuse reflective film covers at least portions of inner surfaces of the walls.
15. A method of forming a diffuse reflective film, comprising:
attaching a bottom layer of reflective specular material to a top layer of polytetrafluoroethylene (PTFE) diffuser material for diffusely reflecting at least 96% of light within the portion of the electromagnetic spectrum between about 400 and about 800 nanometers (nm); and
providing the diffuse reflective film with a thickness of less than 1500 micrometers.
16. A method according to claim 15, wherein the top layer of PTFE diffuser material comprises Zenith™ PTFE-based diffuse reflectance film.
17. A method according to claim 15, wherein the bottom layer of reflective specular material comprises thermally induced phase separation (TPIS) layered polymer film.
18. A method according to claim 15, wherein the top layer of PTFE diffuser material has a thickness of not more than 500 micrometers.
19. A method according to claim 15, wherein the bottom layer of reflective specular material has a thickness of not more than 500 micrometers.
20. A method according to claim 15, wherein an adhesive layer is provided between the top layer of PTFE diffuser material and the bottom layer of reflective specular material.
21. A method according to claim 15, wherein the bottom layer of reflective specular material comprises Vikuiti™ Enhanced Specular Reflector (ESR) layered polymer film.
22. A method according to claim 15, wherein the bottom layer of reflective specular material comprises a metal film.
23. A diffuse reflective film according to claim 1, wherein the bottom layer of reflective specular material comprises Vikuiti™ Enhanced Specular Reflector (ESR) layered polymer film.
24. A diffuse reflective film according to claim 1, wherein the bottom layer of reflective specular material comprises a metal film.
Description
    TECHNICAL FIELD OF THE DISCLOSURE
  • [0001]
    The present disclosure relates to an improved high reflectance material and, in particular, to the creation of a composite material combining polytetrafluoroethylene (PTFE) diffuser material with thermally induced phase separation (TPIS) thin films or thin, highly reflective and specular metal films or substrates resulting in a highly lambertian, highly reflective diffuse material having significant optical benefits over currently available products.
  • BACKGROUND OF THE DISCLOSURE
  • [0002]
    Diffuse reflection provides reflective light luminance at many angles, in contrast to specular or mirror reflection in which light is reflected back only at an angle equal to that of the incident radiation. Typical diffuse reflectors, used for example as white standards for various light measuring test instruments, are made of white inorganic compounds (such as barium sulfate or magnesium oxide) in the form of pressed cake or ceramic tile, all of which are expensive, stiff, and brittle. Other existing diffuse reflectors include (1) microvoided particle-filled articles that depend on a difference in index of refraction of the particles, the surrounding matrix and optional air-filled voids created from stretching, and (2) microporous materials made from a sintered polytetrafluoroethylene suspension. Another useful technology for producing microporous films is thermally induced phase separation (TIPS). Vikuiti™ Enhanced Specular Reflector (ESR) is an example of a material made using TIPS and is an ultra-high reflectivity, mirror-like optical enhancement film, which is available from the Electronic Display Lighting Optical Systems Division of 3M Company (www.3M.com).
  • [0003]
    Effective but inexpensive diffuse reflective films are still needed for the many diverse light management applications that are being developed. Many such applications require that diffuse reflective films be as thin as possible, particularly when the diffuse reflective films are used in electronic displays, such as liquid crystal displays (LCD's) incorporated into notebook computers, handheld computers, portable phones, and other electronic devices. Furthermore, improved reflective films are necessary that efficiently reflect light substantially uniformly across the ultraviolet-visible-near infrared (UV-VIS-NIR) part of the electromagnetic spectrum.
  • SUMMARY OF THE DISCLOSURE
  • [0004]
    The present disclosure provides a diffuse reflective film including a bottom layer of reflective specular material and a top layer of polytetrafluoroethylene (PTFE) diffuser material. The resulting film is preferably flexible and can diffusely reflect radiation substantially uniformly across the UV-VIS-NIR part of the electromagnetic spectrum, e.g., UV-VIS-NIR light having a wavelengths within the 250 to 2500 nanometer (nm) range, and more efficiently than most other known reflectors of similar thickness, e.g., greater than 96% reflective across the UV-VIS-NIR (250-2400 nanometers) part of the spectrum. The diffuse reflective film has a reduced thickness of less than 1500 micrometers, while maintaining a high absolute reflectance value. This reduced thickness allows for creation of various products having a narrow profile, such as liquid crystal display (LCD) illumination systems.
  • [0005]
    According to one aspect of the present disclosure, the top layer of PTFE diffuser material comprises Zenith™ PTFE-based diffuse reflectance film, which is available from SphereOptics-Hoffman LLC (www.sphereoptics.com).
  • [0006]
    According to another aspect of the present disclosure, the bottom layer of reflective specular material comprises a thermally induced phase separation (TPIS) layered polymer film. An example of a suitable TPIS layer polymer film is Vikuiti™ Enhanced Specular Reflector (ESR) layered polymer film, which is available from the Electronic Display Lighting Optical Systems Division of 3M Company (www.3M.com).
  • [0007]
    According to another aspect, the Zenith™ diffuse reflectance film has a thickness of not more than 1000 micrometers, while the bottom layer of reflective specular material has a thickness of not more than 500 micrometers. According to an additional aspect, an adhesive layer is provided between the Zenith™ diffuse reflectance film and the bottom layer of reflective specular material, and an adhesive layer is provided on a bottom surface of the bottom layer of reflective specular material. According to a further aspect, the Zenith™ diffuse reflectance film is placed on the more reflective surface of the bottom layer of reflective specular material (the top and bottom surfaces of the bottom layer of reflective specular material may be different in that one surface is slightly more reflective than the other surface).
  • [0008]
    The bottom layer of reflective specular material can comprise other thin, highly reflective and specular metal films or substrates, and the Zenith™ diffuse material applied to other films and substrates also has enhanced reflectivity and will yield similar results.
  • [0009]
    The present disclosure also provides an optical cavity including a light source in combination with a housing that further contains a diffuse reflector film constructed in accordance with the present disclosure (as described above) lining a portion of the cavity and partially wrapping around the light source so as to direct light from the light source into the optical cavity. The diffuse reflector film reflects light from the light source into the optical cavity, and also reflects light, including recycled light, in the optical cavity toward an open space, such as a room, or toward a viewer.
  • [0010]
    The present disclosure also provides a lamp cavity including a light source, such as a cold cathode fluorescent lamp, in combination with a housing that further contains a diffuse reflector film constructed in accordance with the present disclosure (as described above) lining a portion of the cavity facing the light source and partially wrapping around the light source.
  • [0011]
    Exemplary embodiments of the diffuse reflective film of the present disclosure have been found to be useful in a variety of structures for light management applications. For example, they have been used as a back reflector in display products, such as liquid crystal displays (LCD), flat panels, organic light emitting diodes (OLED) and architectural backlight panels. The diffuse reflective film of the present disclosure may also be used to increase the brightness of sign cabinets, light fibers, instrumentation enclosures, and light conduits. Such articles containing the diffuse reflective films of the present disclosure are further aspects of the present disclosure.
  • [0012]
    Other features and advantages of the present disclosure will be apparent from the following detailed description of the disclosure and the claims. The above summary of principles of the disclosure is not intended to describe each illustrated embodiment or every implementation of the present disclosure. The drawings and the detailed description that follow more particularly exemplify certain preferred embodiments utilizing the principles disclosed herein.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0013]
    FIG. 1 is an enlarged side elevation view of a diffuse reflective film constructed in accordance with the present disclosure and including a bottom layer of reflective specular material, a top layer of polytetrafluoroethylene (PTFE) diffuser material, and a removable protective liner;
  • [0014]
    FIGS. 2-6 are schematic diagrams of exemplary embodiments of liquid crystal display devices incorporating diffuse reflective films constructed in accordance with the present disclosure; and
  • [0015]
    FIG. 7 schematically depicts a cross-section of a light conduit using a diffuse reflective film constructed in accordance with the present disclosure.
  • [0016]
    While principles of the disclosure are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.
  • DETAILED DESCRIPTION
  • [0017]
    Referring to FIG. 1, the present disclosure provides a diffuse reflective film 10 including a bottom or back layer of reflective specular material 12 and a top or front layer 14 of polytetrafluoroethylene (PTFE) diffuser material. The resulting film 10 is preferably flexible such that it can be easily conformed to many different useful configurations, and can diffusely uniformly reflect radiation in the ultraviolet-visible-near infrared (UV-VIS-NIR) range of the electromagnetic spectrum, i.e. between 250 and 2500 nanometers (nm), efficiently. By “efficiently” it is meant, for example, greater than 96% reflective across this portion of the spectrum, than most other known reflectors of similar thickness. The diffuse reflective film 10 has a reduced thickness of less than 1000 micrometers, while maintaining a high absolute reflectance value (it should be noted that the drawing in FIG. 1 is not to scale or proportion and is greatly enlarged to more easily illustrate the different layers). This reduced thickness allows for creation of various products having a narrowed profile, including LCD illumination systems.
  • [0018]
    In the exemplary embodiment of the present disclosure shown in FIG. 2, the top layer 14 of PTFE diffuser material comprises Zenith™ PTFE-based diffuse reflectance film, which is available from SphereOptics-Hoffman LLC (www.sphereoptics.com), while the bottom layer 12 of reflective specular material comprises a thermally induced phase separation (TPIS) layered polymer film. An example of a suitable TPIS layer polymer film is Vikuiti™ Enhanced Specular Reflector (ESR) layered polymer film, which is available from the Electronic Display Lighting Optical Systems Division of 3M Company (www.3M.com). Although it should be understood that the bottom layer of reflective specular material can alternatively comprise thin, highly reflective and specular metal films or substrates, and the Zenith™ diffuse material applied to other metal films and substrates also has enhanced reflectivity and will yield similar results.
  • [0019]
    An adhesive layer is provided between the Zenith™ diffuse reflectance film 14 and the Vikuiti™ ESR layered polymer film 12, and an adhesive layer is provided on a bottom surface of the Vikuiti™ ESR layered polymer film 12. A removably protective layer 16 covers bottom surface of the Vikuiti™ ESR layered polymer film 12 prior to applying the film to a desired surface for reflecting light.
  • [0020]
    The Zenith™ diffuse reflectance film 14 has a thickness of not more than 1000 micrometers, while the Vikuiti™ ESR layered polymer film 12 has a thickness of not more than 500 micrometers. The Zenith™ diffuse reflectance film 14 is placed on the more reflective surface of the Vikuiti™ ESR layered polymer film 12 (the Vikuiti™ ESR layered polymer film's top and bottom surfaces are different in that one surface is slightly more reflective than the other surface).
  • [0021]
    The diffuse reflective film 10 of the present disclosure has a wide variety of light management applications. The diffuse reflective film 10 of the present disclosure may be used to partially line an optical cavity to increase the efficient use of light to illuminate such things as, for example, a partially transparent image that may be either static (such as a graphics film or a transparency) or switchable (such as a liquid crystal display). Thus, optical cavities that are partially lined with a diffuse reflector film 10 of the present disclosure may be used in such devices as backlight units including as liquid crystal display constructions (LCDs), lights, copying machines, projection system displays, OLED display constructions, facsimile apparatus, electronic blackboards, diffuse light standards, and photographic lights. They may also be part of a sign cabinet system, a light conduit or units containing light emitting diodes (LEDs).
  • [0022]
    The diffuse reflective film 10 of the present disclosure has been found to be especially beneficial as a back reflector in back lighting structures used for liquid crystal displays. In this type of application, the article is placed directly behind the light source which is illuminating a display. The film 10 acts to reflect back light which is not directed toward the display and ultimately a viewer. The scattering or diffuse reflection characteristics of the film back reflector also helps provide a more overall diffuse light source and more evenly lit display structure.
  • [0023]
    As used herein, the term “structure” refers to any unit or article capable of holding or supporting the diffuse reflective film 10 in place, such as, for example, a rigid or flexible frame, an awning, umbrella, backlight constructions having both static or moving images, light conduits, light boxes, LCDs, LED displays, sub-components of LCDs, sub-components of LED displays, and reflectors.
  • [0024]
    As used herein, the term “optical cavity” refers to an enclosure designed to contain a light source and direct the light from the light source toward an object benefiting from illumination, such as a static display, a changing image or an insufficiently illuminated object. In certain implementations, the optical cavity includes a lightguide or waveguide.
  • [0025]
    Schematic figures of several structures including liquid crystal displays (LCD) and incorporating the diffuse reflective film 10 constructed in accordance with the present disclosure are shown in FIGS. 2-6. In FIG. 2, a structure 20 is shown that has a fluorescent light source 22 coupled to a plastic light guide 24. Although not shown, a diffuser, a brightness enhancing film, and a reflective polarizer film, for example, can be placed on top of the guide 24 and act to redirect and polarize the light emitted from the plastic light guide 24 towards the LCD and the viewer. If the light is not at the correct range of viewing angles, nor of the correct polarization, it is reflected back towards the light guide 24. The LCD is placed on top of the films and is typically constructed of a liquid crystal sandwiched between two polarizers.
  • [0026]
    The diffuse reflective film 10 acts as a light recycler by (1) reflecting the light rejected from the reflective polarizing film and/or from the brightness enhancement film and (2) gives that light another opportunity to reach a viewer. This rejecting and recycling can occur numerous times increasing the amount of light directed towards the LCD and the viewer.
  • [0027]
    This increased optical efficiency of the diffuse reflective film 10 can be used to reflect incident light between the polarizing and/or brightness enhancement films and the diffuse reflective film 10 to increase display luminance by controlling the angles over which light is emitted. The reflected light is scattered by the diffuse reflective film 10 into all angles. The light within the transmission angles of the polarizing and/or brightness enhancement films is transmitted towards the viewer. Light in the second angular range is reflected for additional scattering.
  • [0028]
    Additionally, the diffuse reflective film 10 may be placed behind or around the light source 22, such as a cold cathode fluorescent lamp to increase light coupling efficiency into the plastic light guide 24.
  • [0029]
    In FIG. 3, another LCD display 30 is shown, containing a light guide 34 and a light source 32. A single piece of the diffuse reflective film 10 covers the bottom surface of the light guide 34, but also wraps around a portion of the light source 32. In this manner, the diffuse reflective film 10 aids in the reflection of light from the light source 32 into the light guide 34, thereby increasing the efficiency of the light guide 34 and also improving the ease of manufacture of the display 30 by forming a single, integrated diffuse reflective film 10 for the display. In addition, the improved single diffuse reflective film 10 avoids any possible loss of light between two separated, diffuse reflective films 10, such as shown in FIG. 2.
  • [0030]
    The increased optical efficiency of the diffuse reflective film 10 is used to increase the reflective efficiency of an optical cavity and/or to mix discrete wavelengths of light to make a uniform colored or white light source. In the schematic drawing of portions of an LCD device 40 shown in FIG. 4, three fluorescent lamps 42 are depicted in an optical cavity 44. All of the lamps 42 may be white or each lamp may be a selected color, such as red, green and blue. The optical cavity 44 is lined with the diffuse reflective film 10 of the present disclosure to both increase reflectance and mix the discrete colors adequately to form a white light source with good spatial light emitting uniformity to illuminate the LCD 40.
  • [0031]
    In FIG. 5, the LCD device 50 is shown with two light emitting diodes (LEDs) 52 as the light source that provides light to an optical cavity 54. The diodes 52 may be colored or white. The optical cavity 54 is lined with the diffuse reflective film 10 of the present disclosure to both increase reflectance and mix the discrete colors adequately to form a white light source with good spatial light emitting uniformity to illuminate the LCD.
  • [0032]
    The device 60 schematically shown in FIG. 6 uses a prismatic light conduit 62 as the light source in an optical cavity 64. The diffuse reflective film 10 of the present disclosure is used both in the light conduit 62 as extractors to scatter light towards the LCD and as back reflectors to reflect the light exiting around the light conduit 64 to form an efficient optical cavity.
  • [0033]
    LEDs are useful light sources for small LCD devices such as medical monitors and automotive displays. LEDs provide the advantages of small size and lower energy consumption, but they have relatively low luminance. The optical efficiency of designs using LED or OLED illumination is increased when a diffuse reflective film 10 of the present disclosure is used as a back reflector in combination with brightness enhancing and reflective polarizer films.
  • [0034]
    The diffuse reflective film 10 of the present disclosure can also be used in OLED displays, which self-emits light under voltage bias, to capture backscatter radiation from the OLED device, redirect the light towards the viewer, and enhance the brightness of the display. The diffuse reflective film 10 would be used in these cases to envelope the OLED display to capture both backscatter, side-scatter and wave-guided energy from the OLED emission.
  • [0035]
    The diffuse reflective film 10 of the present disclosure can also be used to enhance the perceived brightness of microdisplay devices by creating more efficient illumination backlights, and diffuse light illumination delivery structures (light guides and light pipes). The diffuse reflective film 10 helps to uniformly spread out the light over the surface of these microdisplays where non-uniformity can result in severely degraded perception by the viewer due to the magnified optical system viewing the microdisplay.
  • [0036]
    The diffuse reflective film 10 of the present disclosure can be used in plasma flat panel displays and in rear-projection display consoles to develop and deliver an improved uniformity and panel brightness by directing more of the lost backscatter light to the viewed panel plane.
  • [0037]
    The diffuse reflective film 10 of the present disclosure can be used in architectural lighting panels and room lighting to develop and deliver an improved uniformity and panel brightness, especially where there is a need to spread a light uniformly over a very large surface or area. The principle use would be as a cavity reflector or light guide for various types of sources and the diffuse reflective film 10 would be applied to large areas where the light is intended to be delivered to and efficiently reflected from that surface to create an architectural or room lighting effect.
  • [0038]
    The diffuse reflective film 10 can also be used to develop low level laser cavity reflectors, since heat and radiation density effects will not damage the materials.
  • [0039]
    LEDs can replace fluorescent lamps as the preferred backlight source for small liquid crystal displays such as medical monitors and automotive displays. The advantage of using LEDs is their low price, small size and low energy consumption. The disadvantage of LEDs is their relatively low brightness. With the use of the diffuse reflective film 10 of the present disclosure as a back reflector, the brightness of LED displays can be increased.
  • [0040]
    Display sign cabinets that operate more efficiently by improving brightness while requiring less electrical energy can be made using the diffuse reflective film 10 of the present disclosure. Sign cabinets are often made of aluminum backs (generally painted white) and sides (typically unpainted) with fluorescence lights that illuminate a front film to display an image. The luminance that displays the image can be increased if the back and all four sides of the interior are covered with the diffuse reflective film 10 of the present disclosure. Conversely, energy used to illuminate a display film can be proportionately reduced while retaining the same luminance.
  • [0041]
    The diffuse reflective film 10 of the present disclosure is also useful in light conduits or applications wherein light is extracted from or emanates from at least a portion of the length of the hollow light conduit. The source of light for a light conduit is typically a point source such as a metal halide lamp, or in the case of rectangular display conduit a linear light source such as a fluorescent tube may be used. Typical applications are general lighting or display lighting that includes such displays as colored tubes and thin display images and signs.
  • [0042]
    Use of the diffuse reflective film 10 of the present disclosure as extractors or back reflectors increases the lighting efficiency of a light conduit. The diffuse reflection results in a more uniform illumination.
  • [0043]
    One exemplary embodiment of a light conduit structure 70 is shown in FIG. 7. The light conduit 70 is surrounded by an outer shell 72. Inside the outer shell 72 the diffuse reflective film 10 of the present disclosure is placed to reflect any stray light back into the light conduit 70 and out through the emitting surface 74.
  • [0044]
    The above specification is believed to provide a complete description of the manufacture and use of particular embodiments of the present disclosure. Many embodiments of the disclosure can be made without departing from the spirit and scope of the disclosure.
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US4912720 *Oct 27, 1988Mar 27, 1990Labsphere, Inc.Laser cavity material
US5422756 *May 18, 1992Jun 6, 1995Minnesota Mining And Manufacturing CompanyBacklighting system using a retroreflecting polarizer
US5462705 *Jan 14, 1993Oct 31, 1995Labsphere, Inc.Method of forming diffusely reflecting sintered fluorinated long-chain addition polymers doped with pigments for color standard use
US5479009 *Aug 12, 1994Dec 26, 1995Labsphere, Inc.Highly efficient collection optical systems for providing light detectors such as photodetectors and the like with hemispherical fields of view
US5488473 *Mar 1, 1994Jan 30, 1996Labsphere, Inc.Method of and apparatus for increasing measurement sensitivity of fluorescence and luminescence
US5537203 *Feb 16, 1994Jul 16, 1996Labsphere, Inc.Integrated sphere for diffusal reflectance and transmittance
US5596450 *Jan 6, 1995Jan 21, 1997W. L. Gore & Associates, Inc.Light reflectant surface and method for making and using same
US5763519 *Aug 20, 1996Jun 9, 1998Labsphere, Inc.Diffusely reflecting sintered fluorinated long-chain addition polymers doped with pigments for color standard use
US5781342 *Nov 27, 1995Jul 14, 1998W.L. Gore & Associates, Inc.High light diffusive and low light absorbent material and method for making and using same
US5838406 *Aug 29, 1995Nov 17, 1998W. L. Gore & Associates, Inc.Light reflectant surface of expanded polytetrafluoroethylene with nodes and fibrils for backlit liquid crystal displays
US5892621 *Apr 10, 1996Apr 6, 1999W. L. Gore & Associates, Inc.Light reflectant surface for luminaires
US5905594 *Sep 10, 1996May 18, 1999W. L. Gore & Associates, Inc.Light reflectant surface in a recessed cavity substantially surrounding a compact fluorescent lamp
US5923039 *Sep 16, 1997Jul 13, 1999Labsphere, Inc.Ultraviolet transmittance analyzing method and instrument
US5976424 *Jul 31, 1997Nov 2, 1999Minnesota Mining And Manufacturing CompanyMethod for making multilayer optical films having thin optical layers
US5976686 *Oct 24, 1997Nov 2, 19993M Innovative Properties CompanyDiffuse reflective articles
US5982542 *Aug 12, 1997Nov 9, 1999W. L. Gore & Associates, Inc.High light diffusive and low light absorbent material and method for making and using same
US5982548 *May 19, 1997Nov 9, 1999W. L. Gore & Associates, Inc.Thin light reflectant surface and method for making and using same
US6015610 *Nov 14, 1997Jan 18, 2000W. L. Gore & Associates, Inc.Very thin highly light reflectant surface and method for making and using same
US6101032 *Jun 7, 1995Aug 8, 20003M Innovative Properties CompanyLight fixture having a multilayer polymeric film
US6164789 *Jul 12, 1996Dec 26, 2000Honeywell International Inc.Illumination sources and systems
US6186649 *Apr 16, 1998Feb 13, 2001Honeywell International Inc.Linear illumination sources and systems
US6208466 *Nov 25, 1998Mar 27, 20013M Innovative Properties CompanyMultilayer reflector with selective transmission
US6278521 *Nov 30, 1998Aug 21, 2001Labsphere, Inc.Method of and apparatus for bispectral fluorescence colorimetry
US6282821 *Jun 25, 1998Sep 4, 20013M Innovative Properties CompanyLow-loss face diffuser films for backlit signage and methods for using same
US6490104 *Sep 14, 2001Dec 3, 2002Three-Five Systems, Inc.Illumination system for a micro display
US6497946 *Aug 3, 1999Dec 24, 20023M Innovative Properties CompanyDiffuse reflective articles
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7468519 *Dec 5, 2006Dec 23, 2008The Boeing CompanyNear infrared light diffuser
US7481563Sep 21, 2006Jan 27, 20093M Innovative Properties CompanyLED backlight
US7702199 *Mar 31, 2005Apr 20, 2010Essilor InternationalLight pipe for making an electronic display arrangement
US8072616Jun 2, 2008Dec 6, 2011The Boeing CompanyApplication of crossed teflon diffuser to coatings on oriented surfaces
US8077935Apr 22, 2005Dec 13, 2011Validity Sensors, Inc.Methods and apparatus for acquiring a swiped fingerprint image
US8107212Apr 30, 2007Jan 31, 2012Validity Sensors, Inc.Apparatus and method for protecting fingerprint sensing circuitry from electrostatic discharge
US8116540Apr 4, 2008Feb 14, 2012Validity Sensors, Inc.Apparatus and method for reducing noise in fingerprint sensing circuits
US8131026Dec 14, 2007Mar 6, 2012Validity Sensors, Inc.Method and apparatus for fingerprint image reconstruction
US8165355Sep 11, 2006Apr 24, 2012Validity Sensors, Inc.Method and apparatus for fingerprint motion tracking using an in-line array for use in navigation applications
US8175345Apr 15, 2008May 8, 2012Validity Sensors, Inc.Unitized ergonomic two-dimensional fingerprint motion tracking device and method
US8204281Dec 14, 2007Jun 19, 2012Validity Sensors, Inc.System and method to remove artifacts from fingerprint sensor scans
US8224044May 24, 2010Jul 17, 2012Validity Sensors, Inc.Fingerprint sensing assemblies and methods of making
US8229184Dec 14, 2007Jul 24, 2012Validity Sensors, Inc.Method and algorithm for accurate finger motion tracking
US8276816Dec 14, 2007Oct 2, 2012Validity Sensors, Inc.Smart card system with ergonomic fingerprint sensor and method of using
US8278946Jan 15, 2009Oct 2, 2012Validity Sensors, Inc.Apparatus and method for detecting finger activity on a fingerprint sensor
US8290150Jul 17, 2007Oct 16, 2012Validity Sensors, Inc.Method and system for electronically securing an electronic device using physically unclonable functions
US8315444Apr 30, 2012Nov 20, 2012Validity Sensors, Inc.Unitized ergonomic two-dimensional fingerprint motion tracking device and method
US8331096Aug 20, 2010Dec 11, 2012Validity Sensors, Inc.Fingerprint acquisition expansion card apparatus
US8358815Dec 14, 2007Jan 22, 2013Validity Sensors, Inc.Method and apparatus for two-dimensional finger motion tracking and control
US8374407Jan 28, 2009Feb 12, 2013Validity Sensors, Inc.Live finger detection
US8391568Nov 10, 2008Mar 5, 2013Validity Sensors, Inc.System and method for improved scanning of fingerprint edges
US8421890Jan 15, 2010Apr 16, 2013Picofield Technologies, Inc.Electronic imager using an impedance sensor grid array and method of making
US8447077Sep 11, 2006May 21, 2013Validity Sensors, Inc.Method and apparatus for fingerprint motion tracking using an in-line array
US8520913Feb 13, 2012Aug 27, 2013Validity Sensors, Inc.Apparatus and method for reducing noise in fingerprint sensing circuits
US8538097Jan 26, 2011Sep 17, 2013Validity Sensors, Inc.User input utilizing dual line scanner apparatus and method
US8593160Sep 13, 2012Nov 26, 2013Validity Sensors, Inc.Apparatus and method for finger activity on a fingerprint sensor
US8594393Jan 26, 2011Nov 26, 2013Validity SensorsSystem for and method of image reconstruction with dual line scanner using line counts
US8600122Jan 15, 2009Dec 3, 2013Validity Sensors, Inc.Apparatus and method for culling substantially redundant data in fingerprint sensing circuits
US8693736Sep 14, 2012Apr 8, 2014Synaptics IncorporatedSystem for determining the motion of a fingerprint surface with respect to a sensor surface
US8698594Jul 22, 2009Apr 15, 2014Synaptics IncorporatedSystem, device and method for securing a user device component by authenticating the user of a biometric sensor by performance of a replication of a portion of an authentication process performed at a remote computing device
US8716613Mar 2, 2010May 6, 2014Synaptics IncoporatedApparatus and method for electrostatic discharge protection
US8787632Aug 13, 2013Jul 22, 2014Synaptics IncorporatedApparatus and method for reducing noise in fingerprint sensing circuits
US8791792Jun 21, 2010Jul 29, 2014Idex AsaElectronic imager using an impedance sensor grid array mounted on or about a switch and method of making
US8811688Jan 4, 2012Aug 19, 2014Synaptics IncorporatedMethod and apparatus for fingerprint image reconstruction
US8811723Aug 20, 2013Aug 19, 2014Synaptics IncorporatedUser input utilizing dual line scanner apparatus and method
US8866347May 27, 2011Oct 21, 2014Idex AsaBiometric image sensing
US8867799Apr 25, 2012Oct 21, 2014Synaptics IncorporatedFingerprint sensing assemblies and methods of making
US8929619Nov 25, 2013Jan 6, 2015Synaptics IncorporatedSystem and method of image reconstruction with dual line scanner using line counts
US9001040Jun 2, 2010Apr 7, 2015Synaptics IncorporatedIntegrated fingerprint sensor and navigation device
US9137438Feb 8, 2013Sep 15, 2015Synaptics IncorporatedBiometric object sensor and method
US9152838Mar 26, 2013Oct 6, 2015Synaptics IncorporatedFingerprint sensor packagings and methods
US9195877Dec 19, 2012Nov 24, 2015Synaptics IncorporatedMethods and devices for capacitive image sensing
US9230149Sep 14, 2012Jan 5, 2016Idex AsaBiometric image sensing
US9251329Feb 19, 2013Feb 2, 2016Synaptics IncorporatedButton depress wakeup and wakeup strategy
US9268988Sep 14, 2012Feb 23, 2016Idex AsaBiometric image sensing
US9268991Mar 26, 2013Feb 23, 2016Synaptics IncorporatedMethod of and system for enrolling and matching biometric data
US9274553Apr 24, 2012Mar 1, 2016Synaptics IncorporatedFingerprint sensor and integratable electronic display
US9321658 *Aug 29, 2014Apr 26, 2016Crystal Is, Inc.Systems and methods for fluid treatment with homogeneous distribution of ultraviolet light
US9336428Oct 28, 2010May 10, 2016Synaptics IncorporatedIntegrated fingerprint sensor and display
US9400911May 3, 2011Jul 26, 2016Synaptics IncorporatedFingerprint sensor and integratable electronic display
US9406580Mar 14, 2012Aug 2, 2016Synaptics IncorporatedPackaging for fingerprint sensors and methods of manufacture
US9600704Mar 13, 2013Mar 21, 2017Idex AsaElectronic imager using an impedance sensor grid array and method of making
US9600709Feb 5, 2013Mar 21, 2017Synaptics IncorporatedMethods and systems for enrolling biometric data
US9659208Nov 19, 2015May 23, 2017Idex AsaBiometric image sensing
US9665762Feb 13, 2013May 30, 2017Synaptics IncorporatedTiered wakeup strategy
US9666635Feb 21, 2011May 30, 2017Synaptics IncorporatedFingerprint sensing circuit
US20070297056 *Mar 31, 2005Dec 27, 2007Essilor InternationalLight Pipe For Making An Electronic Display Arrangement
US20080074901 *Sep 21, 2006Mar 27, 20083M Innovative Properties CompanyLed backlight
US20080129995 *Dec 5, 2006Jun 5, 2008The Boeing CompanyNear infrared light diffuser
US20080239284 *Jun 2, 2008Oct 2, 2008Vahey Paul GApplication of crossed teflon diffuser to coatings on oriented surfaces
US20090155456 *Dec 14, 2007Jun 18, 2009Validity Sensors, Inc.System and Method for Fingerprint-Resistant Surfaces for Devices Using Fingerprint Sensors
US20100032702 *Jul 31, 2009Feb 11, 2010E. I. Du Pont De Nemours And CompanyLight-Emitting Diode Housing Comprising Fluoropolymer
US20150060692 *Aug 29, 2014Mar 5, 2015Jianfeng ChenSystems and methods for fluid treatment with homogeneous distribution of ultraviolet light
CN101290090BApr 17, 2007Sep 21, 2011财团法人工业技术研究院Checking system light source stray illumination device
CN105473513A *Aug 29, 2014Apr 6, 2016晶体公司Systems and methods for fluid treatment with homogeneous distribution of ultraviolet light
WO2008107823A1 *Feb 28, 2008Sep 12, 2008Philips Intellectual Property & Standards GmbhSystem for providing a laser light output
WO2010019459A2 *Aug 7, 2009Feb 18, 2010E. I. Du Pont De Nemours And CompanyLight-emitting diode housing comprising fluoropolymer
WO2010019459A3 *Aug 7, 2009Apr 22, 2010E. I. Du Pont De Nemours And CompanyLight-emitting diode housing comprising fluoropolymer
Classifications
U.S. Classification428/35.7
International ClassificationB65D1/00, B32B27/08, G02B5/02, G02B5/08
Cooperative ClassificationG02B5/08, G02B5/021, B32B27/08, Y10T428/1352, G02B5/0284
European ClassificationG02B5/02U4, G02B5/02D2, B32B27/08, G02B5/08
Legal Events
DateCodeEventDescription
May 14, 2004ASAssignment
Owner name: SPHEREOPTICS HOFFMAN, LLC, NEW HAMPSHIRE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:DURELL, CHRISTOPHER N.;BOHME, WOLFGANG;REEL/FRAME:015329/0094;SIGNING DATES FROM 20040327 TO 20040408