Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent lens having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent lens to a light emitting device having a stack of layers including semiconductor layers comprising an active region includes elevating a temperature of the lens and the stack and applying a pressure to press the lens and the stack together. Bonding a high refractive index lens to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection. Advantageously, this improvement can be achieved without the use of an encapsulant.

Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element.

Abstract: A device includes a light emitting structure and a wavelength conversion member comprising a semiconductor. The light emitting structure is bonded to the wavelength conversion member. In some embodiments, the light emitting structure is bonded to the wavelength conversion member with an inorganic bonding material. In some embodiments, the light emitting structure is bonded to the wavelength conversion member with a bonding material having an index of refraction greater than 1.5.

Abstract: A lighting apparatus includes a light-emitting diode (LED). A light-conversion layer having multiple non-overlapping regions overlies the light-emitting diode. The light-conversion layer includes at least one first region and at least one second region. In the lighting apparatus, the light-emitting diode is configured to emit light of a first color, the at least one first region is substantially transparent to light of the first color, and the at least one second region converts light of the first color to light of a second color. In an embodiment, the light-conversion layer is configured such that the lighting apparatus provides substantially uniform light of a third color. In some embodiments, the second region includes a phosphor-containing material, and the first region includes silicone or epoxy. In an example, the lighting apparatus uses a blue LED in conjunction with a yellow phosphor material to produce white light.

Abstract: A semiconductor structure includes a light emitting region disposed between an n-type region and a p-type region. A wavelength converting material configured to absorb a portion of the first light emitted by the light emitting region and emit second light is disposed in a path of the first light. A filter is disposed in a path of the first and second light. In some embodiments, the filter absorbs or reflects a fraction of first light at an intensity greater than a predetermined intensity. In some embodiments, the filter absorbs or reflects a portion of the second light. In some embodiments, a quantity of filter material is disposed in the path of the first and second light, then the CCT of the first and second light passing through the filter is detected. Filter material may be removed to correct the detected CCT to a predetermined CCT.

Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element.

Abstract: A method of bonding a transparent optical element to a light emitting device having a stack of layers including semiconductor layers comprising an active region is provided. The method includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the stack together. In one embodiment, the method also includes disposing a layer of a transparent bonding material between the stack and the optical element. The bonding method can be applied to a premade optical element or to a block of optical element material which is later formed or shaped into an optical element such as a lens or an optical concentrator.

Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent optical element (e.g., a lens or an optical concentrator) to a light emitting device comprising an active region includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the light emitting device together. A block of optical element material may be bonded to the light emitting device and then shaped into an optical element. Bonding a high refractive index optical element to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection.

Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent lens having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent lens to a light emitting device having a stack of layers including semiconductor layers comprising an active region includes elevating a temperature of the lens and the stack and applying a pressure to press the lens and the stack together. Bonding a high refractive index lens to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection. Advantageously, this improvement can be achieved without the use of an encapsulant.

Abstract: Heterostructure designs are disclosed that may increase the number of charge carriers available in the quantum well layers of the active region of III-nitride light emitting devices such as light emitting diodes. In a first embodiment, a reservoir layer is included with a barrier layer and quantum well layer in the active region of a light emitting device. In some embodiments, the reservoir layer is thicker than the barrier layer and quantum well layer, and has a greater indium composition than the barrier layer and a smaller indium composition than the quantum well layer. In some embodiments, the reservoir layer is graded. In a second embodiment, the active region of a light emitting device is a superlattice of alternating quantum well layers and barrier layers. In some embodiments, the barrier layers are thin such that charge carriers can tunnel between quantum well layers through a barrier layer.

Abstract: A light emitting device and a method of making the same are provided. The light emitting device includes a light emitting diode and a submount. A phosphormaterial is disposed around at least a portion of the light emitting diode. An underfill is disposed between a first surface of the light emitting diode and a first surface of the submount. The underfill reduces contamination of the light emitting diode by the phosphor material.

Abstract: A method of bonding a transparent optical element to a light emitting device having a stack of layers including semiconductor layers comprising an active region is provided. The method includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the stack together. In one embodiment, the method also includes disposing a layer of a transparent bonding material between the stack and the optical element. The bonding method can be applied to a premade optical element or to a block of optical element material which is later formed or shaped into an optical element such as a lens or an optical concentrator.

Abstract: Heterostructure designs are disclosed that may increase the number of charge carriers available in the quantum well layers of the active region of III-nitride light emitting devices such as light emitting diodes. In a first embodiment, a reservoir layer is included with a barrier layer and quantum well layer in the active region of a light emitting device. In some embodiments, the reservoir layer is thicker than the barrier layer and quantum well layer, and has a greater indium composition than the barrier layer and a smaller indium composition than the quantum well layer. In some embodiments, the reservoir layer is graded. In a second embodiment, the active region of a light emitting device is a superlattice of alternating quantum well layers and barrier layers. In some embodiments, the barrier layers are thin such that charge carriers can tunnel between quantum well layers through a barrier layer.

Abstract: A light emitting device includes a semiconductor light emitting device chip having a top surface and a side surface, a wavelength-converting material overlying at least a portion of the top surface and the side surface of the chip, and a filter material overlying the wavelength-converting material. The chip is capable of emitting light of a first wavelength, the wavelength-converting material is capable of absorbing light of the first wavelength and emitting light of a second wavelength, and the filter material is capable of absorbing light of the first wavelength. In other embodiments, a light emitting device includes a filter material capable of reflecting light of a first wavelength and transmitting light of a second wavelength.

Abstract: A light emitting device includes a semiconductor light emitting device chip having a top surface and a side surface, a wavelength-converting material overlying at least a portion of the top surface and the side surface of the chip, and a filter material overlying the wavelength-converting material. The chip is capable of emitting light of a first wavelength, the wavelength-converting material is capable of absorbing light of the first wavelength and emitting light of a second wavelength, and the filter material is capable of absorbing light of the first wavelength. In other embodiments, a light emitting device includes a filter material capable of reflecting light of a first wavelength and transmitting light of a second wavelength.

Abstract: A light emitting device and a method of making the same are provided. The light emitting device includes a light emitting diode and a submount. A phosphor material is disposed around at least a portion of the light emitting diode. An underfill is disposed between a first surface of the light emitting diode and a first surface of the submount. The underfill reduces contamination of the light emitting diode by the phosphor material.

Abstract: Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent optical element (e.g., a lens or an optical concentrator) to a light emitting device comprising an active region includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the light emitting device together. A block of optical element material may be bonded to the light emitting device and then shaped into an optical element. Bonding a high refractive index optical element to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection.

Abstract: A field emission display (100) includes an electron emitter structure (105) designed to emit an emission current (134), a phosphor (126) disposed to receive at an electron-receiving surface (127) emission current (134), and a multi-layered barrier structure (125) disposed on electron-receiving surface (127) of phosphor (126). Multi-layered barrier structure (125) of the preferred embodiment includes an aluminum layer (128) disposed on electron-receiving surface (127) of phosphor (126) and a carbon layer (129) disposed on aluminum layer (128).

Abstract: A field emission device (100, 150) includes a cathode plate (102, 180) having electron emitters (116), an anode plate (104, 170) having a phosphor (107, 207, 307, 407) activated by electrons (119) emitted by electron emitters (116), and a vacuum bridge focusing structure (118, 158, 218, 318) for focusing electrons (119) emitted by electron emitters (116). Vacuum bridge focusing structure (118, 158, 218, 318) has landings (121, 122, 221, 322), which are attached to cathode plate (102, 180), and further has bridges (120, 220, 320), which extend above and beyond landings (121, 122, 221, 322, 421) to provide a self-supporting structure that is spaced apart from cathode plate (102, 180).

Abstract: A field emission display (100, FIG. 1) having a stabilized phosphor (110, FIG. 1) includes a cathode plate (130, FIG. 1) having a plurality of field emitters (160, FIG. 1), an anode plate (120, FIG. 1) opposing the cathode plate (130, FIG. 1), and a stabilized sulfide phosphor disposed on the anode plate (120, FIG. 1) to receive electrons from the plurality of field emitters (160, FIG. 1). The stabilized sulfide phosphor includes a sulfide phosphor core containing vacuum-unstable sulfur and a stabilized surface made from a more thermodynamically stable material, which is more thermodynamically stable against outgassing than the vacuum-unstable sulfur of the sulfide phosphor core. The stabilized phosphor (110, FIG.