WO2004006214A1 - Module d'affichage comprenant des plaques guides d'ondes disposees les unes sur les autres - Google Patents

Module d'affichage comprenant des plaques guides d'ondes disposees les unes sur les autres Download PDF

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Publication number
WO2004006214A1
WO2004006214A1 PCT/FI2003/000547 FI0300547W WO2004006214A1 WO 2004006214 A1 WO2004006214 A1 WO 2004006214A1 FI 0300547 W FI0300547 W FI 0300547W WO 2004006214 A1 WO2004006214 A1 WO 2004006214A1
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WO
WIPO (PCT)
Prior art keywords
light
display module
waveguide
accordance
outcoupling
Prior art date
Application number
PCT/FI2003/000547
Other languages
English (en)
Inventor
Runar Törnqvist
Original Assignee
Toernqvist Runar
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from FI20021334A external-priority patent/FI20021334A0/fi
Application filed by Toernqvist Runar filed Critical Toernqvist Runar
Priority to AU2003242803A priority Critical patent/AU2003242803A1/en
Publication of WO2004006214A1 publication Critical patent/WO2004006214A1/fr

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Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/0035—Means for improving the coupling-out of light from the light guide provided on the surface of the light guide or in the bulk of it
    • G02B6/0036—2-D arrangement of prisms, protrusions, indentations or roughened surfaces
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
    • G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements

Definitions

  • Display module comprising wave guide plates placed on top of each other
  • the present invention relates to illumination devices.
  • the present invention concerns low information content displays.
  • the display comprises a light source coupled to waveguides having surfaces, which further comprises outcoupling elements, which are capable of diffracting incoming light rays from the light source.
  • Low information content displays typically have a number of segments of the order ten, or even less. In the display devices, each segment is usually lit completely separately from the other segments.
  • high information content displays are mostly based on a matrix structure or a scanning e-beam in Cathode-Ray Tubes (CRT's).
  • CRT's Cathode-Ray Tubes
  • the pixels in the intersections of the columns and the rows of the display are lit depending on the signals provided to the perpendicular electrodes.
  • the number of pixels is usually hundreds of thousands or even more.
  • Typical applications are TV sets and displays for laptops and monitors. Established technologies are active and passive matrix LCD's, CRT's and, more recently, plasma display panels (PDP's).
  • Typical low information content displays are Liquid Crystal Displays (LCD's) used in radio and tape recorder sets, toys, measurement equipment, and various alphanumeric displays. Also Light Emitting Diodes (LED's) are used in low information displays, in particular in alphanumeric display applications.
  • LCD Liquid Crystal Displays
  • LED's Light Emitting Diodes
  • a third established display technology in low information display is vacuum fluorescent displays (NFD) commonly used in alphanumeric displays in measurement equipment, cash registers, and also in car dash boards, especially in U.S.A.
  • a new technology entering this field is organic electroluminescence (OLED).
  • a special category of low information content displays are single message indicators, like exit signs, and single light indicators, where the information is either continuously displayed, or shown in an on/off mode.
  • the most common low information content display technology is the LCD. These are relatively inexpensive and the power consumption is relatively low. Since the LCD panel does not emit light by itself, a backlight or, in some cases, front light, is needed to make the display visible in low ambient illumination. The backlight consumes power. Powder electroluminescence light panels were earlier commonly used as back lights. These light panels are now more and more replaced by a separate back light source and a diffuser waveguide, which distributes the light over the display area. Back light sources are either LED's or CCFL's (cold cathode fluorescent light), depending on the size of the display. The backlight and the diffuser waveguide represent often a significant fraction of the cost of a low information content LCD display. There are limitations with the LCD's, because the speed of the LCD material and the switching on of the CCFL's become issues at very low temperatures. The polarizing filters limit the use at high temperatures.
  • LED's are generally more costly than LCD's. On the other hand, LED's emit light and they are, therefore, visible under different light conditions. Good brightness uniformity is only achieved by adding light spreading optics, which increases costs.
  • VFD's are limited to small display, which are also relatively expensive. Like the LED's, VFD's emit light.
  • OLED technology has not yet penetrated the market, mostly because of retained image problems and the need for encapsulation that increases costs.
  • Light emitting surfaces with uniform brightness have been developed for backlights in LCD's. They are usually based on waveguide panels with a surface designed so that the outcoupling of the light provides a uniform brightness. That is, the outcoupling elements are designed so that the outcoupling increases with the distance from the light source.
  • the light source can be either a CCFL or an LED.
  • There are different techniques for achieving the desired outcoupling profile such as painting of white dots with different density on the backside of the plate, forming bumps using a technique used by, e.g. Global Lighting Technologies, or using a pattern with grooves, which form microprisms (e.g. Brite View, see SID International Symposium, Application Digest Pll (1994) or P3 (1995).
  • a key item is to design the diffractive pattern so that the brightness does not depend on the distance from the light source (or light sources). That is, the pattern is a function of the distance from the light source (sources). Typically, the pattern if formed by groves, stripes, possibly pixelated, or dots, and the periodicity is in general in the range of 1.5 to 10 ⁇ m. The height of the pattern is usually of the order of 0.5 ⁇ m.
  • An advantage associated with waveguide panels, where a LED is used, resides in the fact that a very slim structure, having a thickness of even less than 1 mm can be achieved.
  • Other advantages are inexpensive manufacturing technology for high volume production using injection molding, high light outcoupling efficiency and a shock resistant device structure functional at both very low and very high temperatures.
  • the light waveguide plate with the outcoupling elements elements can be divided in sections, so that LED's with different colors light up different sections, as taught by FI Patents Nos. 106992 and 107085 with reference to light signs using diffractive elements. This makes it possible to use the light panels and light indicators described in said patents as low information content displays.
  • Figure 1 shows the light panel (Fig. la), an enlarged image of the diffraction pattern in top view (Fig. lb), alternative cross-sections of the diffraction patterns (Fig. lc) and the propagation of light in the waveguide (Fig. Id).
  • the present invention is based on the idea of stacking a plurality of waveguides plates with light outcoupling elements, such as diffractive elements or micro lenses or prisms, on top of each other, so as to provide a stacked construction.
  • the plates comprise waveguides having outcoupling, e.g. diffractive, elements, which are capable of diffracting light rays from the light source to the surface of the waveguide.
  • the waveguide layers are essentially transparent and, according to the invention, each one of them is capable of displaying its own message (symbol, character, letter, number or similar sign), as shown in Figure 2.
  • the number of completely different, in all regards mutually independent messages that can be shown corresponds to the number of waveguide layers in the display. More specifically, the invention is mainly characterized by what is stated in the characterizing part of claim 1.
  • the invention provides considerable advantages. Thus, by the present display modules it is possible to show a plurality of, typically 2 to 6, different signs in the same area.
  • the invention makes use of the compactness and cost effectiveness of the waveguides with diffractive elements described above to make a new type of displays to replace more costly and more bulky LCD and LED panels used in certain low information content applications.
  • Figures 1 depicts in a schematic fashion a prior art light sign based on a single waveguide layer with diffractive elements, whereby Fig. 1 shows the light panel, Fig. lb shows a top view of the diffraction pattern, and Figs, lc and Id show alternative cross-sections of the diffraction patterns and the propagation of light in the waveguide, respectively;
  • Figures 2 shows in a similar way a display module comprising two waveguide layer with outcoupling patterns on the surface according to a preferred embodiment of the invention, whereby Figures 2a and 2b show top views, Figure 2c a cross-section of the module in side view and Figure 2d an enlarged cross-section in side view;
  • Figures 3 depicts the simplified construction of a display module comprising three waveguide layers (Figs.
  • Figures 4 depicts schematically the configuration of a display module comprising four waveguide layers (Figs. 4a to 4d) with diffractive patterns on the lower surfaces; and Figures 5a and 5b shows how the light sources can be arranged in the comers of three waveguide layers in an embodiment according to Figures 3 in order to reduce light losses through the edges of the waveguide.
  • one basic idea of this invention is to stack transparent, semi- transparent or colored waveguides plates with outcoupling elements on top of each other, so that each waveguide layer displays its own message, as illustrated in Figure 2.
  • Transparent waveguide plates are preferred.
  • the individual waveguide layers can show their own symbols, characters, letters, numbers and similar signs, whereby by stacking of such layers on top of each other it is possible to form a simple, intelligent display, in which the displayed message can easily be changed.
  • the losses of light intensity of such plates should be not more than about 5 %/cm, preferably less than 1 %/cm, when light travels through the plate.
  • the waveguide When the waveguide is colored, it absorbs in some part of the spectrum, which feature can be used for enhancing contrast in that very ambient by using a light source emitting in the region where the absorption is low.
  • Fig. 2a shows a top view of the display module exhibiting the superimposed patterns of the two layers (Fig 2b).
  • Fig. 2c shows the cross-section of the display module from the side
  • Fig. 2d shows enlarged cross-sections of a part of the layers indicating the propagation of light emitted from a light source.
  • the light sources 11, 12 are place at opposite sides of the display module.
  • outcoupling elements e.g. diffractive grating
  • the outcoupling elements can be provided on either side of the waveguide, i.e. on the top or on the bottom surfaces, or even on both sides.
  • the messages comprise generally light patterns, such as symbols, characters, letters, numbers and the like.
  • each layer can, in principle, consist of several wavguide plates, that are lit up separately with different colors if so desired.
  • the preferred light source is an LED, but also other light sources can be used.
  • the light source, in particular the LED, can be directly coupled to the waveguide with the outcoupling elements.
  • the light source can be coupled to the waveguide by using optical fibers.
  • the outcoupling elements can be of any kind meeting the display requirements in that specific application. That is, the performance of the display in terms of picture quality, efficiency and cost objectives dictates what outcoupling technology should be chosen.
  • the technologies applied to backlight waveguides that were mentioned above can be employed in the embodiment of the present invention.
  • the disclosure of US Patent No. 6014 192 is herewith incorporated by reference.
  • One advantageous outcoupling element approach is based on using diffractive elements, in particular when a point source type of light source is used (e.g. LED).
  • the diffractive elements can, e.g., comprise grating structures with grooves and stripes. It is also possible to use ray optical elements, including (micro)lenses and prisms.
  • the diffracting element is capable of diffracting light rays from the light source in a direction substantially perpendicular to the surface of the waveguide.
  • the waveguides are essentially made of transparent material as described in prior art (e.g. polycarbonate). Injection molding is the preferred manufacturing as this invention addresses the need for cost effective displays in high volume production.
  • the basic principle applies also for other manufacturing technologies like e.g. UV-casting
  • diffractive outcoupling elements are used, these are similar to those used to create a surface with uniform light emission, but not identical to those described in FI 106323, FI 106992, FI 107085.
  • the diffractive pattern has to be designed, so that adequately uniform light emission is obtained taking into account the very different type of symbols or characters to be displayed. In many cases there is no need to design the outcoupling elements so that they depend on the distance from the light source. That is, a uniform outcoupling pattern is often adequate.
  • the outcoupling pattern can be constant. It is, however, possible to construct the outcoupling elements as suggested in the art such that the outcoupling pattern varies with distance from the light source in order to create uniform light emission.
  • the waveguide panels or plates should preferably be designed so that light propagates at a right angle, or at an angle of at least 60°, in two adjacent layers in order not to generate shadow pictures.
  • the outcoupling elements should be designed so that outcoupling is high in the direction of the light propagating in that very layer, but low, preferably below 10 %, for light propagating in the direction of the light in the adjacent layers.
  • the layers are either in direct contact with each other or the clearance between them is less than 1 mm, typically less than 0.5 mm, usually less than 0.2 mm. It is equally important to avoid that there are parallel grooves or stripes in the diffractive pattern in adjacent layers, as this tends to smear the images.
  • semitransparent light scattering films can be placed under the waveguides, as illustrated by Figures 2a to 2d, Figures 3a to 3c and Figures 4a to 4d. It is preferred to allow the transmission of the light scattering films decrease towards the bottom layers, and the light scattering film, in the following also called "diffusing foil", fitted under the lowest waveguide panel should be opaque to achieve maximum light scattering or reflection.
  • the diffractive elements are designed so that the outcoupled light is essentially deflected out from the waveguide plate at an angle close to 90 degrees (almost perpendicularly).
  • the deflection is within the range of 60 to 90 degrees, preferably 75 to 90 degrees against the planar surface of the plate. In that case, a part of the light is deflected towards the viewer, a part in the other direction (from where it can be reflected by using a mirror-like back plate if higher luminance is sought).
  • a light absorbing back plate it is advantageous to use a light absorbing back plate to enhance contrast.
  • the diffractive elements typically some 60 % of the light is deflected from the diffractive elements back through the waveguide plate, and 40 % is deflected out to the ambient through the diffractive elements.
  • some 60 % of the light is then deflected towards the viewer through the waveguide plate and 40 % is deflected out on the backside.
  • Placing of the diffractive elements on the front side of the plate will reverse the situation.
  • outcoupling elements both scattering and diffractive gratings
  • the outcoupling elements are designed so that the light is coupled out over a large light emission angle.
  • a diffusely reflecting film - reflecting over a large angle - is then placed behind the waveguide.
  • the light emission in the front is also observed over a wide angle.
  • the diffractive elements grating
  • the diffractive elements so that the light outcoupling is essentially perpendicular to the surface of the waveguide plate, better crispness of the edges and less absorption in the outcoupling elements in the upper layers is achieved.
  • This embodiment is particularly interesting when a lower light emission intensity (luminance) is acceptable when watching the display at a larger angle from normal incidence.
  • a display module in accordance with the invention can comprise a light absorbing background fitted behind the lowest waveguide plate or a reflecting surface behind the lowest waveguide plate.
  • the waveguide plates with the bump patterns are formed by injection molding using e.g. techniques developed by Global Lightning Technologies as described in Wireless Design Online, July 12, 2000.
  • a semitransparent light scattering plastic foil (fabricated e.g. by 3M) is placed between the waveguide plates.
  • An opaque light scattering film is placed below the lower plate.
  • Each arrow has an area 2.5 cm 2 , and each arrow is lit up by two yellow LED, 2c and 2d, respectively. These give the arrows a luminance of about 200 cd/m when the LED's are operated under normal conditions (near 20 mA).
  • the preferred direction of the light from the LED's are opposite in the two waveguide layers as illustrated in Figures 2b to 2d.
  • each waveguide element there are three waveguide elements on top of each other, Figures 3a, 3b and 3c.
  • Each one is 1.2 mm thick and made of polycarbonate (PC) using embossing or injection moulding techniques.
  • a diffractive pattern forming the words ON, OFF and READY, is formed in each waveguide respectively.
  • the areas of the words are 1.4 cm 2 , 1.7 and 1.0 cm 2 , respectively, and the waveguides are lit up by a two green, two red and two yellow LED's, 21, 22, 23, in each layer, respectively.
  • the LED's are placed so that the light propagates in different directions in each layer, as shown in Figures 3a, 3b and 3c.
  • thin commercially available semitransparent scattering plastic foils are placed below the two topmost waveguides without any intentional airgap in-between.
  • the light scattering foil under the lowest layer is opaque.
  • the luminance of the letters is 50 -150 cd/m 2 when the surface mounted LED's are operated at a driving current of near 20 mA.
  • FIG. 3 In the embodiment shown in Figure 3 can also be carried out as follows: three waveguide elements are placed on top of each other. Each one is 0.8 mm thick and made of polycarbonate (PC) using embossing or injection moulding techniques. A diffractive pattern forming the words ON, OFF and READY, is formed in each waveguide respectively. The diffractive patterns are designed so that approximately 60 % of the light is reflected back through the waveguide plate towards the viewer, and approximately 40 % is coupled out in the opposite direction. The areas of the words are 1.4 cm 2 , 1.7 and 1.0 cm 2 , respectively, and the waveguides are lit up by a four green, four white and four green LED's in each layer, respectively.
  • PC polycarbonate
  • the LED's are placed so that the light propagates at 90 degrees angles in adjacent layers. There is only a small air gap ( ⁇ 0.1 mm) between the waveguide plates and there is a light absorbing layer black plastic layer under the or lowest waveguide layer (OFF) in order to enhance the contrast in high ambient light. To further enhance contrast, there is gray filter with a 12.5 % transmission in front of the stack with the three waveguides.
  • the luminance of the letters is typically 40 -100 cd/m 2 when the surface mounted LED's are operated at driving current near 25 mA.
  • the LED's, 31 - 33 can be placed in the corners of the rectangular (including quadratic) structures. Preferably, they are placed in adjacent corners in adjacent waveguide plates, so that light propagates at 90 degrees angles in adjacent wavewguide layers.
  • the plates need not be exactly rectangular (quadratic), although this is the most preferred embodiment.
  • the placing of the light source in the comer somewhat reduces the outcoupling of the light through the edges of the lightguide (waveguide) plate due to maximization of the reflection at the edges. This is caused by a high incident angle (measured from the normal to the surface).
  • Each waveguide is made of UV casting an epoxy film deposited on a 0.7 mm thick glass substrate.
  • the light scattering foil 4f under the lowest layer is opaque. The light from the LED's is coupled to the waveguide plates with the aid of optical fibers.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Optics & Photonics (AREA)
  • Planar Illumination Modules (AREA)
  • Illuminated Signs And Luminous Advertising (AREA)

Abstract

L'invention concerne un module d'affichage à faible quantité d'informations. Cet affichage comprend au moins deux plaques guides d'ondes disposées l'une sur l'autre; chaque plaque étant couplée à une source lumineuse et présentant un motif de découplage sur au moins l'une de ses surfaces de manière à découpler la lumière provenant de la source lumineuse afin de former un motif lumineux. Le mode de réalisation décrit dans cette invention permet d'afficher plusieurs motifs lumineux dans la même zone du module d'affichage.
PCT/FI2003/000547 2002-07-05 2003-07-04 Module d'affichage comprenant des plaques guides d'ondes disposees les unes sur les autres WO2004006214A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003242803A AU2003242803A1 (en) 2002-07-05 2003-07-04 Display module comprising wave guide plates placed on top of each other

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
FI20021334A FI20021334A0 (fi) 2002-07-05 2002-07-05 Näyttömoduuli
FI20021334 2002-07-05
FI20022227A FI117453B (sv) 2002-07-05 2002-12-18 Displaymodul
FI20022227 2002-12-18

Publications (1)

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WO2004006214A1 true WO2004006214A1 (fr) 2004-01-15

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AU (1) AU2003242803A1 (fr)
FI (1) FI117453B (fr)
WO (1) WO2004006214A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006072494A1 (fr) * 2004-12-30 2006-07-13 BSH Bosch und Siemens Hausgeräte GmbH Identification en couleur de textes ou symboles dans un afficheur a cristaux liquides monochrome
WO2007117350A1 (fr) * 2006-04-11 2007-10-18 Sony Ericsson Mobile Communications Ab Systeme d'affichage a guides optiques permettant l'affichage d'une pluralite de motifs
US8172444B2 (en) 2009-04-24 2012-05-08 Avago Technologies Ecbu Ip (Singapore) Pte. Ltd. Light guide display with multiple light guide layers
DE102011016429A1 (de) * 2011-04-08 2012-10-11 GM Global Technology Operations LLC (n. d. Gesetzen des Staates Delaware) Anzeigeschaltereinheit für ein Fahrzeug und Verfahren zur Herstellung der Anzeigeschaltereinheit
WO2014028265A1 (fr) * 2012-08-13 2014-02-20 3M Innovative Properties Company Dispositifs d'éclairage à impression à motifs d'attributs d'extraction diffractifs
US10605980B2 (en) 2017-06-04 2020-03-31 Svv Technology Innovations, Inc. Stepped light guide illumination systems

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5029985A (en) * 1988-05-19 1991-07-09 Ricoh Company, Ltd. Multilayer liquid crystal display device
JPH1114835A (ja) * 1997-06-20 1999-01-22 Shimada Precision Kk 発光表示板
EP0969306A1 (fr) * 1998-01-20 2000-01-05 Seiko Epson Corporation Dispositif de commutation optique et dispositif d'affichage d'images
US6014192A (en) * 1996-07-16 2000-01-11 Thomson-Csf Illumination device and application thereof to the illumination of a transmissive screen
WO2000004408A1 (fr) * 1998-07-16 2000-01-27 Brookhaven Science Associates Panneau d'affichage a redirection de lumiere et procede de fabrication d'un panneau d'affichage a redirection de lumiere
EP1016817A1 (fr) * 1998-12-30 2000-07-05 Nokia Mobile Phones Ltd. Conduit de lumière pour retro-éclairage d'un dispositif d'affichage plat
US6317545B1 (en) * 1999-09-01 2001-11-13 James T. Veligdan Stepped inlet optical panel

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5029985A (en) * 1988-05-19 1991-07-09 Ricoh Company, Ltd. Multilayer liquid crystal display device
US6014192A (en) * 1996-07-16 2000-01-11 Thomson-Csf Illumination device and application thereof to the illumination of a transmissive screen
JPH1114835A (ja) * 1997-06-20 1999-01-22 Shimada Precision Kk 発光表示板
EP0969306A1 (fr) * 1998-01-20 2000-01-05 Seiko Epson Corporation Dispositif de commutation optique et dispositif d'affichage d'images
WO2000004408A1 (fr) * 1998-07-16 2000-01-27 Brookhaven Science Associates Panneau d'affichage a redirection de lumiere et procede de fabrication d'un panneau d'affichage a redirection de lumiere
EP1016817A1 (fr) * 1998-12-30 2000-07-05 Nokia Mobile Phones Ltd. Conduit de lumière pour retro-éclairage d'un dispositif d'affichage plat
US6317545B1 (en) * 1999-09-01 2001-11-13 James T. Veligdan Stepped inlet optical panel

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006072494A1 (fr) * 2004-12-30 2006-07-13 BSH Bosch und Siemens Hausgeräte GmbH Identification en couleur de textes ou symboles dans un afficheur a cristaux liquides monochrome
US8130347B2 (en) 2004-12-30 2012-03-06 Bsh Bosch Und Siemens Hausgeraete Gmbh Colored marking of texts or symbols in a monochrome LC display
WO2007117350A1 (fr) * 2006-04-11 2007-10-18 Sony Ericsson Mobile Communications Ab Systeme d'affichage a guides optiques permettant l'affichage d'une pluralite de motifs
US7762702B2 (en) 2006-04-11 2010-07-27 Sony Ericsson Mobile Communications Ab Light guide display systems and related methods, systems, and computer program products
US8172444B2 (en) 2009-04-24 2012-05-08 Avago Technologies Ecbu Ip (Singapore) Pte. Ltd. Light guide display with multiple light guide layers
DE102011016429A1 (de) * 2011-04-08 2012-10-11 GM Global Technology Operations LLC (n. d. Gesetzen des Staates Delaware) Anzeigeschaltereinheit für ein Fahrzeug und Verfahren zur Herstellung der Anzeigeschaltereinheit
US8789989B2 (en) 2011-04-08 2014-07-29 GM Global Technology Operations LLC Display switch unit for a vehicle and method for producing the display switch unit
WO2014028265A1 (fr) * 2012-08-13 2014-02-20 3M Innovative Properties Company Dispositifs d'éclairage à impression à motifs d'attributs d'extraction diffractifs
US8834004B2 (en) 2012-08-13 2014-09-16 3M Innovative Properties Company Lighting devices with patterned printing of diffractive extraction features
US9470838B2 (en) 2012-08-13 2016-10-18 3M Innovative Properties Company Lighting devices with patterned printing of diffractive extraction features
US10605980B2 (en) 2017-06-04 2020-03-31 Svv Technology Innovations, Inc. Stepped light guide illumination systems
US10908350B2 (en) 2017-06-04 2021-02-02 S.V.V. Technology Innovations, Inc Stepped light guide illumination systems

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Publication number Publication date
FI20022227A0 (fi) 2002-12-18
FI117453B (sv) 2006-10-13
AU2003242803A1 (en) 2004-01-23

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