Abstract: The present invention relates to a LED module which converts pump light from a LED chip (120) to light at another wavelength, which is emitted from the module. The conversion takes place in a portion of a luminescent material (124). The color purity of the LED module is enhanced by reducing any leakage of pump light using a reflector in combination with an absorber. In one embodiment, the absorber is integrated as one or several thin absorbing layers between the layers of a multi-layer reflection filter (126); this may yield an even higher reduction of pump light leakage from the module.

Abstract: The present invention relates to a light emitting device, comprising: a LED die (10) having a first surface (12), a second surface (14) and at least one side facet (16) connecting the first and the second surface (12, 14). Further, the LED die comprises a light polarizing layer (20), a light blocking layer (30), and a light reflecting layer (40). The light polarizing layer (20) is arranged on the first surface (12), the light blocking layer (30) is arranged on the at least one side facet (16), and the light reflecting layer (40) is arranged on the second surface (14) of the LED die.

Abstract: A side-emitting light emitting device (100) is provided, comprising at least one light emitting diode (101) arranged on a substrate (102) and facing a scattering reflector (103, 109) disposed at a distance from and extending along the extension of said substrate. The scattering reflector comprises scattering components (110) distributed in a carrier (108), and the scattering components have a refractive index being different from the refractive index of said carrier. The scattering action of the reflector gives rise to an angular redistribution in the device, which increases the chance of light exiting the device through lateral openings between the reflector and the substrate, while light is essentially prevented from being emitted through the top surface.

Abstract: A side-emitting light emitting device (100) is provided, comprising a substrate (101), a reflector (102) arranged spaced apart from said substrate (101) and extending along the extension of said substrate, and at least one light emitting diode (103) arranged on said substrate and facing said reflector, said substrate (101) and reflector (102) delimiting a wave guiding region (104) for light emitted by said at least one light emitting diode (103). Further, a wavelength converting material (105) is arranged at the lateral edge of said wave guiding region (104). The invention provides a compact side emitter with controlled color emission.

Abstract: The invention relates to a composition comprising a binder material and nanoparticles having an average particle size of 100 nm or less having a first refractive index of at least 1.65 in respect of light of a first wavelength, and a second refractive index in the range of 1.60-2.2 in respect of light of a second wavelength, wherein said first refractive index is higher than said second refractive index, and wherein the first and second refractive indices may be tuned by adjusting the volume ratio of the nanoparticles to the binder material. The composition may improve light extraction when used for bonding a ceramic member to an LED, and/or may reduce the amount of light that is directed back towards the LED.

Abstract: The present invention relates to an optical element for a light emitting device, wherein the optical element comprises a sintered ceramic body (3) comprising a wavelength converting layer (4) and a scattering layer (5), and to a method of manufacturing thereof. More specifically, the invention relates to an optical element, comprising a sintered ceramic body (3) of a first layer (4) and a second layer (5) arranged on the first layer, wherein the first layer comprises a wavelength converting material, the porosity of the second layer is higher than the porosity of the first layer, and pores in the second layer are arranged to provide scattering of a light beam.

Abstract: The present invention relates to a LED module which converts pump light from a LED chip (120) to light at another wavelength, which is emitted from the module. The conversion takes place in a portion of a luminescent material (124). The color purity of the LED module is enhanced by reducing any leakage of pump light using a reflector in combination with an absorber. In one embodiment, the absorber is integrated as one or several thin absorbing layers between the layers of a multi-layer reflection filter (126); this may yield an even higher reduction of pump light leakage from the module.

Abstract: The present invention relates to the field of luminous devices, in particular to a luminous device (1) comprising a light transmissive element (2). The light transmissive element further comprises a semiconductor diode structure (3) for generating light, a reflecting section (22) for reflecting light from the diode structure (3) into the light transmissive element (2) and an output section (21) for outputting light from the diode structure (3). The luminous device (1) further comprises a reflecting structure (4), at least partially enclosing side surfaces of the light transmissive element (2), for reflecting light from the diode structure (3) towards the output section (21).

Abstract: A side-emitting light emitting device (100) is provided, comprising a substrate (101), a reflector (102) arranged spaced apart from said substrate (101) and extending along the extension of said substrate, and at least one light emitting diode (103) arranged on said substrate and facing said reflector, said substrate (101) and reflector (102) delimiting a wave guiding region (104) for light emitted by said at least one light emitting diode (103). Further, a wavelength converting material (105) is arranged at the lateral edge of said wave guiding region (104). The invention provides a compact side emitter with controlled color emission.

Abstract: A side-emitting light emitting device (100) is provided, comprising at least one light emitting diode (101) arranged on a substrate (102) and facing a scattering reflector (103, 109) disposed at a distance from and extending along the extension of said substrate. The reflector comprises a plurality of non-parallel oriented reflective flakes (112) distributed in a transmissive carrier (113), such that light incident thereon from any angle of incidence is reflected and scattered. The scattering action of the reflector gives rise to an angular redistribution in the device, which increases the chance of light exiting the device through lateral openings between the reflector and the substrate, while the opacity of the reflector prevents light from being emitted through the top surface.

Abstract: A side-emitting light emitting device (100) is provided, comprising at least one light emitting diode (101) arranged on a substrate (102) and facing a scattering reflector (103, 109) disposed at a distance from and extending along the extension of said substrate. The scattering reflector comprises scattering components (110) distributed in a carrier (108), and the scattering components have a refractive index being different from the refractive index of said carrier. The scattering action of the reflector gives rise to an angular redistribution in the device, which increases the chance of light exiting the device through lateral openings between the reflector and the substrate, while light is essentially prevented from being emitted through the top surface.

Abstract: The present invention relates to a light emitting device, comprising: a LED die (10) having a first surface (12), a second surface (14) and at least one side facet (16) connecting the first and the second surface (12, 14). Further, the LED die comprises a light polarizing layer (20), a light blocking layer (30), and a light reflecting layer (40). The light polarizing layer (20) is arranged on the first surface (12), the light blocking layer (30) is arranged on the at least one side facet (16), and the light reflecting layer (40) is arranged on the second surface (14) of the LED die.

Abstract: An optical element (50; 72a-d; 80; 90), which has a first optical member (1; 51; 86; 93; 101) with at least one indentation (2a-f; 20; 25; 30; 35; 40; 57a-c; 100) at a first surface (3) thereof, and a second optical member (5; 52; 87a-c; 94; 104) attached to the first surface (3) of the first optical member (1; 51; 86; 93; 101), this second optical member (5; 52; 87a-c; 94; 104) essentially conforming to the at least one indentation (2a-f; 20; 25; 30; 35; 40; 57a-c; 100) in the first optical member. The optical element further comprises at least one reflector (9-10; 55a-c; 85a-c; 92a-e) at an interface between the first and second optical members, the at least one reflector being located at the at least one indentation. The reflector (9-10; 55a-c; 85a-c; 92a-e) is formed by an interface between a cavity (8) formed between the first and second optical members and one of the first and second optical members.

Abstract: A method for the manufacture of a birefringent layer with tilted optical axis, comprising providing a liquid crystal mixture comprising liquid crystal molecules and a volatile surfactant, aligning said liquid crystal mixture, and evaporate at least part of said volatile compound from the mixture to alter the tilt of the optical axis of said liquid crystal mixture.

Abstract: A display device comprising a plurality of independently addressable pixels (1) comprising: a first substrate (2); a counter-electrode (3); second substrate (4); a stack of electrochromic layers (5a, 5b, 5c) associated with said second substrate (4); an electrolyte (6) disposed between said counter-electrode (3) and said stack of electrochromic layers (5a, 5b, 5c). Said electrochromic layers (5a, 5b, 5c) are each independently addressable for switching operation; and separated from each other by layers of an electrolyte (7).

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: 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 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: 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.