Abstract: The invention relates to an illumination module (1) comprising a plurality of light sources (2) distributed over a light guiding plate (3) accommodating said light sources and capable of guiding light of said light sources through at least a portion of said plate. The light guiding plate has one or more out-coupling structures (4), preferably arranged around each light source, so that at least a portion of the light emitted by a first light source (2A) and at least a portion of the light emitted by a second adjacent light source (2B) mix within said light guiding plate before leaving said illumination module as a single substantially collimated mixed light beam. The invention further relates to a lamp and a display apparatus comprising such an illumination module.

Abstract: A mirror device (1) which can be simultaneously used for display purposes, based on e.g. an LCD display (5) with a polarizing mirror (2) placed in front of it. The polarizing mirror (2) has the characteristics that it does not disturb the transmission of the light from the display (5), but does reflect the light from outside the area of the screen.

Abstract: A collimator for use in an optical device, such as a display device, includes a multi-layered sheet of at least five alternating light transmitting and light impervious layers. A collimation angle of a few degrees is obtainable using the collimator. The collimator may be produced by co-extruding or injection molding.

Abstract: The electrophoretic multi-color display device has a plurality of cells (10, 10?, 10?, . . . ) with an electrophoretic medium (14) and pixel electrodes (11, 11?, 11?, . . . ) for selecting a subgroup of cells. A color filter array (13) is associated with the pixel electrodes. The color filter array (13) and the pixel electrodes (11, 11?, 11?, . . . ) are provided at the same side of the electrophoretic medium (14). Preferably, the cells (10, 10?, 10?, . . . ) of the color filter array (13) are arranged according to a matrix and are disposed along lines registering with the pixel electrodes (11, 11?, 11?, . . . ). Preferably, an insulating material (17) with a relatively low refractive index is provided between the pixel electrodes (11, 11?, 11? . . . ) and the color filter array (13). Preferably, the insulating material (17) is selected from the group formed by a fluor-polymer, a low-dielectric inorganic film and a low-dielectric nano-porous film.

Abstract: A multi-layered arrangement according to the invention provide emission of polarized light. At least one of the interfacing surfaces between the layers is provided with a microstructure. In one embodiment, a first layer in the form of a lightguide substrate (401) receives unpolarized light from a lamp (420). A birefringent second layer (402) is provided with a microstructure (410) in the form of parallel grooves. On top of the birefringent layer a third layer (403), i.e. a coating layer, is located. Light is outcoupled by way of selective Total Internal Reflection, TIR, at the micro-structured surface of the birefringent layer, yielding a highly linearly polarized emission at near normal angles. The polarized light may be emitted out through the coating or in an opposite direction through the lightguide, which in an advantageous manner allow any configuration of transmissive (backlight), transflective (backlight) or reflective (frontlight) display arrangement.

Abstract: A polarized light emitting waveguide plate comprises an entrance side for coupling light into the wave guide plate, a major exit surface for coupling light out of the waveguide plate, and a polarizer for selectively directing a component of a first polarization state of light coupled in via the entrance side towards the exit surface, the polarizer comprising an anisotropically light scattering layer which selectively scatters the component of the first polarization state towards the exit surface. Preferably, the waveguide plate is made of conventionally processed polymeric materials in the form of a laminate of waveguide substrate, anisotropically light scattering layer and, optionally, an optically transparent cover layer.

Abstract: The present invention relates to a light generating device comprising a slab light guide (1), at least one light input unit (2) arranged on at least one side (10) of said light guide (1) comprising at least one light source (20) and a light incoupling means (21) for coupling light into said light guide (1), and at least one light output unit (3) arranged on at least one side (11) of said light guide (1). In order to provide a device that provides polarized light of a high homogeneity the light output unit (3) according to the present invention comprises a polarized light emitting waveguide plate (31) for selectively coupling light of a first polarization state out of said light guide (1). The present invention further relates to a display device, in particular an LCD, comprising a light generating device according to the invention.

Abstract: A side-lit illumination arrangement comprises a polarized-light-emitting waveguide comprising a polarization-selective beam-splitting interface formed at an interface of a waveguiding layer and a polarization-selection layer. In order to avoid alignment problems occurring during the manufacture of the waveguide which impair the proper functioning of the polarization-selective beam-splitting interface, the polarization-selective beam-splitting interface is planar. Waveguided light polarized and transmitted by the polarization-selective beam-splitting interface into the polarization-selection layer is coupled out by a relief-structured surface via an exit surface. Display devices having such waveguides, in particular if used in a front light, have a high brightness and efficiency.

Abstract: Pixels of a display device include a reservoir containing two immiscible fluids. Switching of a pixel state is based on redistribution of the fluids within the reservoir due to electrostatic forced applied onto electrodes, and a potential applied to one of the fluids which is electrically conducting.

Abstract: A back lighting system for illuminating a display device comprises a light-emitting panel (1) and a light source (6) for coupling light into the light-emitting panel. The light source comprises a low-pressure discharge lamp (6; 7). The light source additionally comprises a plurality of LEDs (8, 8?, . . . ; 9, 9?, . . . ) for selectively setting the color temperature of the light emitted by the light source. Preferably, the LEDs increase the color temperature of the light emitted by the light source. Preferably, the light emitted by the back lighting system ranges from 6,000 to 10,500 K. Preferably, the LEDs are blue light emitting LEDs, each preferably having a luminous flux of at least 5 lm. The color point of an image to be displayed on a display screen of the display device is set by the back lighting system, thus enabling an optimum contrast to be achieved for the image to be displayed by the display device.

Abstract: An arrangement for providing polarized light to, e.g. a LCD, is disclosed. The arrangement comprises a substrate (201) and a top layer (202). The substrate (201) is preferably optically anisotropic and the top layer (202) is either isotropic or anisotropic. The respective indices of refraction are chosen such that polarization separation occurs at the interface (214) between the substrate (201) and the top layer (202). Furthermore, the indices of refraction are chosen such that there are no restrictions on the angle of incidence (&thgr;i) of the incoming light (L), and hence obviating the need for collimation of the incoming light (L). The top layer (202) comprises light outcoupling structures, internally or externally.

Abstract: Display cells (10) contain two immiscible fluids (3, 4) having different refractive index orabsorption coefficient, the cells being placed below a transparent substrate (10) having a prismatic structure enabling total internal reflection (TIR). Switching is based on frustrated TIR by (re)distribution of the fluids within the cell due to elecrostatic forces on (external) electrodes (5, 6) and a potential applied to one of the fluids (4) which is electrically conducting.

Abstract: Transflective display device has an optical waveguide commonly known as a light guide. The guide includes areas having a chiral nematic structure which splits light coming in from aside into two light beams having a mutually opposite circular polarization. Polarization splitting is achieved at the interface of the areas having the chiral nematic structure.

Abstract: A polarized light-emitting waveguide for use in an edge-lit lighting arrangement has polarization-selective outcoupling structure including at least a volume hologram for selectively diffracting waveguided light towards the exit surface of the waveguide with high contrast and efficiency. The light emitted by the waveguide is selectively emitted to one side thereof, highly polarized, highly collimated and may be homogeneously distributed across the exit surface. Also, light emission may be normal or near-normal to the exit surface. If combined with light recycling means the contrast, brightness and/or efficiency of the edge-lit illumination arrangement may be further increased.

Abstract: A polarized light emitting waveguide plate (60) comprises an entrance side (64) for coupling light into the wave guide plate (60), a major exit surface (65) for coupling light out of the waveguide plate, and polarization means for selectively directing a component of a first polarization state of light coupled in via the entrance side (64) towards the exit surface (65), the polarization means comprising an anisotropically light scattering layer (26) which selectively scatters the component of the first polarization state towards the exit surface (65). In a preferred embodiment the waveguide plate (60) is made of conventionally processed polymeric materials in the form of a laminate of waveguide substrate (68), anisotropically light scattering layer(26) and, optionally, an optically transparent cover layer (69).

Abstract: The invention relates to a switching mirror display having an increased aperture. The display comprises pixel elements (20) having a switchable layer (3), which is switched between a reflecting and an absorbing state by changing a hydrogen content of the switchable layer (3). Applying a DC voltage on electroconductive layers (11, 13) changes the hydrogen content. These electroconductive layers (11, 13) sandwich a stack of layers comprising the switchable layer (3), which stack has been deposited on a transparent substrate (1). The display is being viewed from a side (24) of the substrate on which the stack is deposited. The pixel element (20) is driven by an active matrix element (22). The switchable layer (3) extends across the active matrix element (22) and conceals this element. This increases the aperture of the display.

Abstract: Transflective display device provided with an optical waveguide which splits light coming in from aside into two light beams having a mutually opposite circular polarization. Polarization splitting is achieved at the interface of areas in the optical waveguide having a chiral nematic structure.

Abstract: The invention relates to a display operating either in a reflective mode or a transmissive mode and having a high brightness. The display comprises pixel elements (20) having a switchable layer (3), which is switched between a reflecting, a transmissive and an absorbing state by changing a hydrogen content of the switchable layer. Applying a DC voltage on electroconductive layers (11, 13) changes the hydrogen content. These electroconductive layers sandwich a stack of layers comprising the switchable layer (3), which stack has been deposited on a transparent substrate.

Abstract: An arrangement for providing polarized light to, e.g. a LCD, is disclosed. The arrangement comprises a substrate (201) and a top layer (202). The substrate (201) is preferably optically anisotropic and the top layer (202) is either isotropic or anisotropic. The respective indices of refraction are chosen such that polarization separation occurs at the interface (214) between the substrate (201) and the top layer (202). Furthermore, the indices of refraction are chosen such that there are no restrictions on the angle of incidence (&thgr;i) of the incoming light (L), and hence obviating the need for collimation of the incoming light (L). The top layer (202) comprises light outcoupling structures, internally or externally.

Abstract: A back-lit colour display is disclosed, in which light from a backlight is filtered by a reflective filter structure arranged on a viewing side of the backlight. The reflective filter structure defines pixels having sub-pixels of red, green and blue colour. According to the invention, the filter structure comprises reflective regions having reflection bands that jointly cover the complete visible range of the spectrum, such that no gaps are present between the reflection bands. Preferably, the emission from the backlight is narrow band, and selected in such a way that the peak emission wavelength is within the corresponding reflection band, but close to the short wavelength cut-off thereof. Furthermore, the emission from the backlight is preferably selected to have a suitable overlap with the tri-stimulus functions of the human eye.