Abstract: A light emitting device comprises: a package; at least one red LED housed in the package and operable to emit red light; at least one blue LED housed in the package and operable to emit blue light wherein the emission product of the device comprises the combination of light emitted by the red and blue LEDs; and a light transmissive material encapsulating the LEDs. Preferably, the package further comprises electrical contacts that are configured such that the drive current of the blue and red LEDs is independently controllable. Devices and/or light emitting systems further comprise a driver operable to control a drive current of the red and/or blue LEDs in response the measured emission intensities of the LEDs such as to maintain a substantially constant ratio of the blue to red light in the emission product.

Abstract: A color temperature tunable white light source comprises: first and second LED arrangements operable to emit light of first and second wavelength range respectively that are configured such that their combined light output, which comprises light generated by the source, appears white in color. One or both LED arrangements comprises a phosphor provided remote to an associated LED operable to generate excitation radiation and to irradiate the phosphor such that it emits light of a different wavelength range, wherein the light emitted by the LED arrangement comprises the combined light from the LED and phosphor. The color temperature of output white light is tunable by controlling the relative light outputs of the LED arrangements by for example controlling the relative magnitude of the drive currents of the LEDs or a duty cycle of a pulse width modulated drive current.

Abstract: A lamp comprises a thermally conductive body comprising a cavity having a first opening and a plurality of second openings and one or more LED mounted in thermal communication with the thermally conductive body. The cavity and the first and second openings are configured such that in operation air moves through the cavity between the first opening and the second opening by thermal convection to provide cooling of the thermally conductive body. Where the thermally conductive body is symmetrical the cavity can extend coaxially within the body. The first opening can be on an end surface of the body whilst the second openings are on a side surface. The can be configured such that the outer surface of the lamp has a form factor that resembles the envelope of an incandescent light bulb; resembles an MR-16 halogen reflector lamp or resembles an MR-11 halogen reflector lamp.

Abstract: A lamp comprises: a dish-shaped (parabolic); an LED operable to generate excitation light; a light guide configured to extend along an axis of the reflector, wherein light generated by the at least one LED is coupled into a first end of the light guide and wherein light is emitted from the light guide at a light emitting surface that is in proximity to a second end of the light guide and at least one phosphor material provided as a layer on at least a part of the light emitting surface of the light guide. An LED light bulb is also disclosed.

Abstract: An LED-lamp (lighting bar) comprises a plurality of solid state light emitters (LEDs) configured as an elongate (linear) array and a generally concave cylindrical light reflective surface disposed along the length of the array of LEDs. The concave light reflective surface is configured to direct light over an illumination plane located to a side of the lamp. The LEDs can be configured such that their emission axes are oriented to the illumination plane at an angle of between 0° and 90. The lamp can further comprise a second generally concave cylindrical light reflective surface in which the concave light reflective surfaces are configured to direct light over illumination planes located on respective sides of the lamp. There is also disclosed a panel lamp and sign incorporating the lamp(s) of the invention.

Abstract: An LED spotlight that is operable to emit light with a selected emission angle measured relative to an emission axis of the spotlight comprises: a dish shaped (parabolic) reflector and a plurality of LEDs, wherein the LEDs are configured such that in operation each emits light in a generally radial direction to the emission axis of the spotlight and wherein the light emission axis of the LEDs is configured at an angle to the emission axis of the spotlight of at least 40°. In preferred embodiments the LEDs are configured such that their emission axis is substantially orthogonal to the emission axis of the spotlight and the reflector comprises a respective parabolic light reflective surface portion associated with a respective one of the LEDs.

Abstract: A photoluminescent composition (“phosphor ink”) comprises a suspension of particles of at least one blue light (380 nm to 480 nm) excitable phosphor material in a light transmissive liquid binder in which the weight loading of at least one phosphor material to binder material is in a range 40% to 75%. The binder can be U.V. curable, thermally curable, solvent based or a combination thereof and comprise a polymer resin; a monomer resin, an acrylic, a silicone or a fluorinated polymer. The composition can further comprise particles of a light reflective material suspended in the liquid binder. Photoluminescence wavelength conversion components; solid-state light emitting devices; light emitting signage surfaces and light emitting signage utilizing the composition are disclosed.

Abstract: A light emitting device includes a radiation source operable to generate and radiate excitation energy, the source being configured to irradiate a wavelength conversion component with excitation energy and the wavelength conversion component comprising a layer of photo-luminescent material configured to emit radiation of a selected color when irradiated by the radiation source and a color enhancement filter layer configured to filter undesirable wavelengths of an emission product of the layer of photo-luminescent material to establish a final emission product for the light emitting device.

Abstract: A solid-state lamp comprises a light guide having at least one light emitting face and at least one solid-state light source (LED) configured to couple light into the light guide. The lamp further comprises a pattern of light extracting features for promoting emission of light from the light guide wherein the pattern of light extracting features is formed on at least one face of the light guide.

Abstract: A light emitting device comprises an excitation source (20), one or more light emitting diode(s) operable to generate excitation light of a first wavelength range (?1) and a light emitting surface (14) having a phosphor material (26) which absorbs at least a part of the excitation light and emits light of a second wavelength range (?2), wherein light (32) emitted by the device comprises combined light of the first and second wavelength ranges emitted by the light emitting surface. The device is characterized by the light emitting surface having one or more window areas (28) which does not include a phosphor material and which are substantially transparent to light of the first and second wavelengths. The light emitting surface can comprise a transparent substrate (14) having a pattern of phosphor material on a surface thereof with the one or more window areas evenly distributed over the light emitting surface.

Abstract: Disclosed herein are green-emitting, garnet-based phosphors having the formula (Lu1-a-b-cYaTbbAc)3(Al1-dBd)5(O1-eCe)12:Ce,Eu, where A is selected from the group consisting of Mg, Sr, Ca, and Ba; B is selected from the group consisting of Ga and In; C is selected from the group consisting of F, Cl, and Br; and 0?a?1; 0?b?1; 0<c?0.5; 0?d?1; and 0<e?0.2. These phosphors are distinguished from anything in the art by nature of their inclusion of both an alkaline earth and a halogen. Their peak emission wavelength may lie between about 500 nm and 540 nm; in one embodiment, the phosphor (Lu,Y,A)3Al5(O,F,Cl)12:Eu2+ has an emission at 540 nm. The FWHM of the emission peak lies between 80 nm and 150 nm. The present green garnet phosphors may be combined with a red-emitting, nitride-based phosphor such as CaAlSiN3 to produce white light.

Abstract: A solid-state light emitting device having a solid-state light emitter (LED) operable to generate excitation light and a wavelength conversion component including a mixture of particles of a photoluminescence material and particles of a light reflective material. In operation the phosphor absorbs at least a portion of the excitation light and emits light of a different color. The emission product of the device comprises the combined light generated by the LED and the phosphor. The wavelength conversion component can be light transmissive and comprise a light transmissive substrate on which the mixture of phosphor and reflective materials is provided as a layer or homogeneously distributed throughout the volume of the substrate. Alternatively the wavelength conversion component can be light reflective with the mixture of phosphor and light reflective materials being provided as a layer on the light reflective surface.

Abstract: A light emitting device comprises at least one solid-state light source (LED) operable to generate excitation light and a wavelength conversion component located remotely to the at least one source and operable to convert at least a portion of the excitation light to light of a different wavelength. The wavelength conversion component includes a light transmissive substrate having a wavelength conversion layer comprising particles of at least one photoluminescence material and a light diffusing layer comprising particles of a light diffractive material. This approach of using the light diffusing layer in combination with the wavelength conversion layer solves the problem of variations or non-uniformities in the color of emitted light with emission angle.

Abstract: A light emitting device comprises at least one solid-state light source (LED) operable to generate excitation light and a wavelength conversion component located remotely to the at least one source and operable to convert at least a portion of the excitation light to light of a different wavelength. The wavelength conversion component comprises a light transmissive substrate having a wavelength conversion layer comprising particles of at least one photoluminescence material and a light diffusing layer comprising particles of a light diffractive material. This approach of using the light diffusing layer in combination with the wavelength conversion layer solves the problem of variations or non-uniformities in the color of emitted light with emission angle. In addition, the color appearance of the lighting apparatus in its OFF state can be improved by implementing the light diffusing layer in combination with the wavelength conversion layer.

Abstract: A light emitting device comprises at least one solid-state light source (LED) operable to generate excitation light and a wavelength conversion component located remotely to the at least one source and operable to convert at least a portion of the excitation light to light of a different wavelength. The wavelength conversion component comprises a light transmissive substrate having a wavelength conversion layer comprising particles of at least one photoluminescence material and a light diffusing layer comprising particles of a light diffractive material. This approach of using the light diffusing layer in combination with the wavelength conversion layer solves the problem of variations or non-uniformities in the color of emitted light with emission angle. In addition, the color appearance of the lighting apparatus in its OFF state can be improved by implementing the light diffusing layer in combination with the wavelength conversion layer.

Abstract: A light emitting device comprises at least one light emitter, typically an LED, operable to generate blue light and a wavelength conversion component. The wavelength conversion component can be light transmissive or light reflective and comprises at least two phosphor materials that are operable to absorb at least a portion of said blue light and emit light of different colors and wherein the emission product of the device comprises the combined light generated by the LED(s) and the phosphor materials. The phosphor materials are configured as a pattern of non-overlapping areas on a surface of the component.

Abstract: An LED lighting device comprises: a thermally conducting body having an at least one opening that connects with a cavity within the body and a plurality of LEDs mounted in thermal communication with a face of the body and positioned around the opening. One or more passages pass through the body from the cavity to an outer surface of the body and are configured such that in operation air moves through the cavity by thermal convection thereby to provide cooling of the body. Each passage is configured in a direction that extends in a direction at an angle of about 45° to a line that is parallel with the axis of the body toward the outer surface of the body away from the face. The body can be configured such that its outer surface has a form factor resembling an incandescent light bulb or halogen reflector lamp.

Abstract: Disclosed herein are cerium doped, garnet phosphors emitting in the yellow region of the spectrum, and having the general formula (Y,A)3(Al,B)5(O,C)12:Ce3+, where A is Tb, Gd, Sm, La, Sr, Ba, Ca, and/or Mg, and substitutes for Y, B is Si, Ge, B, P, and/or Ga, and substitutes for Al, and C is F, Cl, N, and/or S, where C substitutes for O. Relative to a solid-state-reaction method, the instant co-precipitation methods provide a more homogeneous mixing environment to enhance the distribution of the Ce3+ activator in the YAG matrix. Such a uniform distribution has the benefit of an increased emission intensity. The primary particle size of the as-prepared phosphor is about 200 nm, with a narrow distribution.

Abstract: Embodiments of the present invention are directed a ?-SiAlON:Eu2+ based green emitting phosphor having the formula Eux(A1)6?z(A2)zOyN8?z(A3)2(x+z?y), where 0<z?4.2; 0?y?z; 0<x?0.1; A1 is Si, C, Ge, and/or Sn; A2 is Al, B, Ga, and/or In; A3 is F, Cl, Br, and/or I. The new set of compounds described by Eux(A1)6?z(A2)zOyN8?z(A3)2(x+z?y) have the same structure as ?-Si3N4. Both elements A1 and A2 reside on Si sites, and both O and N occupy the nitrogen sites of the ?-Si3N4 crystal structure. A molar quantity (z?y) of the A3?anion (defined as a halogen) reside on nitrogen sites.

Abstract: A light emitting system comprises an LED-based light emitting device and a controller for controlling operation of the device. The device comprises at least two LEDs that are operable to generate light of different colors that contribute to the emission product of the device. The controller is operable to control light emission from the LEDs in response to the measured intensity of the first and second color light contributions in the emission product. To measure the individual light contributions the controller is operable to interrupt, or at least change, light emission from one LED for a selected time period and during this time period to measure the intensity of the emission product of the device. The intensity of light of the first and second color can be determined by comparing the measured intensity with the measured intensity when the light emission from the other LED is interrupted or changed.