1061 results about "Color rendering index" patented technology

A method for the manufacturing of white LEDs is proposed, which can achieve a tunable color rendering index (CRI) or luminosity through the use of at least two phosphor composition layers of essentially the same emission color coordinates, each composition including at least one individual phosphor compound. The method allows to optimize the devices for CRI at a given minimal luminosity requirement, or vice versa.

A warm white light emitting apparatus includes a first light emitting diode (LED)-phosphor combination to generatea base light that is white or yellowish white and a second LED-phosphor combination to generate a Color Rendering Index (CRI) adjusting light. The base light the CRI adjusting light together make a warm white light having a color temperature of 2500 to 4500K.

In a wavelength converted semiconductor light emitting device with at least two wavelength converting materials, the wavelength converting materials in the device are arranged relative to the light emitting device and relative to each other to tailor interaction between the different wavelength converting materials in order to maximize one or more of the luminous equivalent, color rendering index, and color gamut of the combined visible light emitted by the device.

The invention discloses a high efficiency incandescent and Compact Fluorescent (CFL) bulb replacement LED lamp having a good color reproduction. The LED light bulb includes two groups of semiconductor light emitters and a luminescent material to emit four different spectrums of light. The two groups of semiconductor light emitters are enclosed around an interior wall of the light bulb housing, which has a plurality of fins at an exterior surface for effective heat dissipation. A high reflective member having a dome shape in the center is disposed under the two groups of semiconductor light emitters to redirect the emission and excitation lights from the two groups of semiconductor light emitters and recycle the backscattered light for multi-spectrum light mixing. The LED-light bulb further includes a single power line connecting to the two groups of semiconductor light emitters and a high efficiency electrical AC / DC conversion and control device. The light bulb has a diffuser dome for an output window and a conventional Edison-mount screw-type light bulb socket, a conventional fluorescent tube coupler arrangement or a conventional halogen MR-16 socket arrangement connecting to an AC power base. If a voltage is supplied to the AC / DC conversion and control device, a mixture light from the diffuser dome produces a warm white light with a color rendering index of at least 85 and a luminous efficacy of at least 80 lumens per watt.

A light emitting device includes at least three light emitting source and a phosphor, with the three light sources consisted of following light emitting diodes (LED) emitting lights having different wavelengths. Wherein, two light sources are used to excite the phosphor to produce a distinct wavelength different from those of the two light sources. The distinct wavelength is blended with portions of the two light sources and a light source from another independent light source, and a blended light is released to obtain a white light having an excellent color rendering index.

A lighting apparatus includes a first source of monochromatic light, a second source of white light, and a third source of polychromatic light. The light from the three sources combine to produce a resultant color of light from the apparatus. The intensities of the light emitted by the first, second and third sources are independently controlled by a controller to produce a desired resultant color of light. Varying the amount of electric current applied to each such light source by substantially an equal amounts to changes the luminance of the combined light with out affecting the resultant color. The lighting apparatus can be operated to replicate a Planckian radiator with a color rendering index of at least 80 throughout a substantial portion of the visible light spectrum produced by the lighting apparatus.

An electric lamp includes a first light source and a second light source and power circuitry configured to selectively energize the first light source and the second light source. The first light source is configured to produce light that is substantially free of wavelengths below about 530 nanometers, and the second light source is configured to product light having wavelengths of less than about 530 nanometers. The electric lamp is configured to produce white or near-white light in a variety of color temperatures, while retaining good color rendering index.

A broad bandwidth light source including: a solid state light emitting device that generates short wavelength light; and quantum dot material and phosphor material that are each irradiated by some of the short wavelength light. The short wavelength light has a spectrum with a first peak wavelength shorter than about 500 nm. The quantum dot material absorbs some of the short wavelength light and reemits it as long wavelength light having a spectrum with a second peak wavelength longer than about 600 nm. The phosphor material absorbs some of the short wavelength light and reemits it as mid wavelength light having a spectrum with a peak wavelength between the first and second peak wavelength. The light source is configured such that some of each light (short, mid, and long wavelength) is emitted coincidently as a light having a chromaticity value near the blackbody locus and a color rendering index greater than 80.

An illumination device comprising a housing fixture, a light source, and an active heat transfer device is provided. The housing fixture includes a base adapted to be receivable in a light fixture receptacle configured to receive a gas-discharge lamp. The light source emits light with a color rendering index higher than a respective color rendering index of at least a type of gas-discharge lamp. The active heat transfer device is physically coupled to the light source and mounted to the housing fixture. The active heat transfer device receives power from a power supply to remove thermal energy from the light source.

A new fluorescent lamp comprises a lamp tube and an electronic ballast, it is characterized in that it is provided with an outer tube, there are respectively an outer plug at both ends of the outer tube, in which inserts a socket for the lamp tube. The electronic ballast is between the outer plug and the socket for the lamp tube at one end, said lamp tube is disposed between two sockets for the lamp tube. There are advantages as follows: an urgent lighting, the electronic ballast and the compact lamp tube are integrated as one whole; it is convenient for mounting and exchanging, a cost for mounting is greatly reduced; it is possible for repacking to maintain an original means, to reduce a contamination of waste; its weight is light; its power factor is high, more than 95%, it is economical in power, a cost for transporting is low; the color rendering index (CRI) is more than 80%; it is ignited immediately after it is turned on, it does not flash; it is applied to lamps having deferent power; the life of the lamp tube is prolonged by 50%; its output brightness is higher than existing lamps by twice or more; the lamp tube still steadily operates when a power supply is unexpected to be shut off, which reduces accident cases; the whole distortion of a resonant wave becomes smaller than 30%.

A lighting apparatus includes a first source of monochromatic light, a second source of white light, and a third source of polychromatic light. The light from the three sources combine to produce a resultant color of light from the apparatus. The intensities of the light emitted by the first, second and third sources are independently controlled by a controller to produce a desired resultant color of light. Varying the amount of electric current applied to each such light source by substantially an equal amounts to changes the luminance of the combined light with out affecting the resultant color. The lighting apparatus can be operated to replicate a Planckian radiator with a color rendering index of at least 80 throughout a substantial portion of the visible light spectrum produced by the lighting apparatus.

A white light LED is provided. The white light LED includes an exciting light source and a fluorescent powder, wherein the wavelength of the light emitting from the exciting light source is in a range of about 250 nm to about 490 nmt. The fluorescent powder is disposed around the exciting light source to receive the light emitting from the exciting light source. Furthermore, the material of the fluorescent powder includes (Tb3-x-yCexRey)Al5O12, (Me1-x-yEuxRey)3SiO5, YBO3:Ce3+, YBO3:Tb3+, SrGa2O4:Eu2+, SrAl2O4:Eu2+, (Ba,Sr)MgAl10:Eu2+, Mn2+, Y2O3:Eu3+, Y2O3:Bi3+, (Y,Gd)2O3:Eu3+, (Y,Gd)2O3:Bi3+, Y2O2S:Eu3+, Y2O2S:Bi3+, (Me1-xEux)ReS, 6MgO,As2O5:Mn, Mg3SiO4:Mn, BaMgAl10O17:Eu2+ and (Ca,Sr,Ba)5(PO4)3Cl:Eu2+,Gd3+. The white light LED of the invention provides high luminous efficiency and excellent color rendering index.

A light emitting device including a phosphor blend including four or more phosphors emitting within a specific spectral range to optimize the color rendering index (CRI) for a given color coordinated temperature (CCT). The blend will include at least four phosphors selected from the following: a blue phosphor having an emission peak at 400-500 nm, a green phosphor having an emission peak at 500-575 nm, an orange phosphor having an emission peak from 575-615 nm, and a deep red phosphor having an emission peak at 615-680 nm. The preferred blends are used to make light sources with general CRI values (Ra) greater than 95 at CCT's from about 2500 to 8000 K.

Methods and apparatus for providing circadian-friendly LED light sources are disclosed. A light source is formed to include a first LED emission (e.g., one or more LEDs emitting a first spectrum) and a second LED emission (e.g., one or more LEDs emitting a second spectrum) wherein the first and second LED emissions are combined in a first ratio and in a second ratio such that while changing from the first ratio to the second ratio the relative circadian stimulation is varied while maintaining a color rendering index above 80.

A broad bandwidth light source including: a solid state light emitting device that generates short wavelength light; and quantum dot material and phosphor material that are each irradiated by some of the short wavelength light. The short wavelength light has a spectrum with a first peak wavelength shorter than about 500 nm. The quantum dot material absorbs some of the short wavelength light and reemits it as long wavelength light having a spectrum with a second peak wavelength longer than about 600 nm. The phosphor material absorbs some of the short wavelength light and reemits it as mid wavelength light having a spectrum with a peak wavelength between the first and second peak wavelength. The light source is configured such that some of each light (short, mid, and long wavelength) is emitted coincidentally as a light having a chromaticity value near the blackbody locus and a color rendering index greater than 80.

Disclosed herein is a light fixture. The light fixture includes at least one first light source that emits at a peak wavelength in a range of approximately 380 nm to approximately 420 nm and at least one second light source that emits at a different peak wavelength, wherein a combined light output of the at least one first light source and the at least one second light source emits a colored light that is perceived as white light. The white light is defined by having a color rendering index (CRI) value of more than approximately 50. The at least one second light source that emits at a different peak wavelength consists of an xy coordinate on a International Commission on Illumination (CIE) 1931 xy color space diagram above a black body curve within a bounded area defined by a first line of approximately y=2.23989x−0.382773 and a second line of approximately y=1.1551x−0.195082. The combined light output has a proportion of spectral energy measured in the approximately 380 nm to approximately 420 nm range of greater than approximately 20%.

This invention provides a phosphor material capable of absorbing primary light and converting that light into white light having a high color rendering index and illumination devices made from the phosphor material. The white light may have a color rendering index of 100 and may be produced with an efficiency of at least 30 lm / w. In one embodiment, the illumination device includes a secondary light source made from a plurality of Group IV semiconductor nanoparticles.

A tunable color LED module comprises at least two sub-modules, each comprising an LED (104), a wavelength converting element (WCE) (201, 112, 203) and a reflector cup. The total light emitted by the module comprises light generated from each LED and WCE and the module is configured to emit a total light having a predefined color chromaticity when activation properties of the LEDs are managed appropriately. The total light may have a broad white emission spectrum (106). The module combines the benefits of a low cost with uniform chromaticity properties in the far field, and offers long and controlled lifetime at the same time as flexibility and intelligence of tunable color chromaticity, Color Rendering Index (CRI) and intensity, either at manufacture or in an end user lighting application. A controlled LED module system comprises a control system for the managing activation properties of the LEDs in the sub-modules. Also described is a method of manufacture.

Disclosed herein is a light fixture. The light fixture includes at least one first light source that emits at a peak wavelength in a range of approximately 380 nm to approximately 420 nm and at least one second light source that emits at a different peak wavelength, wherein a combined light output of the at least one first light source and the at least one second light source emits a colored light that is perceived as white light. The white light is defined by having a color rendering index (CRI) value of more than approximately 50. The at least one second light source that emits at a different peak wavelength consists of an xy coordinate on a International Commission on Illumination (CIE) 1931 xy color space diagram above a black body curve within a bounded area defined by a first line of approximately y=2.23989x−0.382773 and a second line of approximately y=1.1551x−0.195082. The combined light output has a proportion of spectral energy measured in the approximately 380 nm to approximately 420 nm range of greater than approximately 20%.

LED packages, and LED lamps and bulbs, are disclosed that are arranged to minimize the CRI and efficiency losses resulting from the overlap of conversion material emission and excitation spectrum. In different devices having conversion materials with this overlap, the present invention arranges the conversion materials to reduce the likelihood that re-emitted light from a first conversion materials will encounter the second conversion material to minimize the risk of re-absorption. In some embodiments this risk is minimized by different arrangements where there is separation between the two phosphors. In some embodiments this separation results less than 50% of re-emitted light from the one phosphor passing into the phosphor where it risks re-absorption.

A white light LED having high color rendering indices and a correlated color temperature similar to that of an incandescent lamp. The LED has a semiconductor body formed of a semiconductor layer sequence capable of emitting electromagnetic radiation in a blue spectral range, the radiation exciting a yellow phosphor resulting in an intermediate blue-yellow light output whose chromaticity coordinates are transformed by a casting compound encompassing the semiconductor body and phosphor. A colored tint blended with epoxy resin forms the casting compound and filters the blue-yellow output, passing the red wavelength components of the blue-yellow output while attenuating the blue-yellow spectral wavelength, resulting in a balanced white output having a correlated color temperature, chromaticity coordinates, and color rendering indices similar to that of-an incandescent lamp output.

A fluorescent lamp including a phosphor layer comprising a phosphor blend including four or more optimized phosphors emitting within a specific spectral range to optimize luminosity for a given color rendering index (CRI) and color coordinated temperature (CCT). The blend will include at least four phosphors selected from the following: a blue phosphor having an emission peak at 440-490 nm, a blue-green phosphor having an emission peak at 475-525 nm, a green phosphor having an emission peak at 515-550 nm, an orange phosphor having an emission peak from 550-600 nm, a deep red phosphor having an emission peak at 615-665 nm, and a red phosphor having an emission peak at 600-670 nm.

An illuminating device comprises one or more luminescent devices (1). The luminescent device comprises a semiconductor light emitting element (10) emitting a excitation light having an peak within a wavelength range from 350 nm to 430 nm, and a luminescent part (20) comprising a sealing member (22) and a phosphor (21) absorbing the light from the semiconductor light emitting element (10) and emitting a light with different emission spectrum. For the luminescent device (1), an excitation light contribution degree ΔE, an index quantitatively representing what extent of a visible component of the excitation light is involved in color mixing of a combined light of the luminescent device (1), is 0.005 or less, and a mean color rendering index Ra is 70 or more.

A method and system for controlling lighting in a space reduces energy consumption of the light sources by changing at least one of the color rendering index (CRI) and the correlated color temperature (CCT) while maintaining illumination levels. Preferably, the method and system sense movement of people in the space relative to light sources that light the space, and automatically and individually adjust plural solid state lighting devices that form each of the respective light sources to a first lighting condition when people are in a first position, wherein the lamps respectively emit light of a first illumination level and a first CRI at a first electrical power level, and to a second lighting condition when people are in a second position, wherein the light sources respectively emit light of the first illumination level and a smaller CRI than the first CRI and at a lower electrical power level than the first electrical power level.

A correlated color temperature (CCT) modulating method including following steps is provided. A white LED light source is modulated to emit a first white light. At least one LED light source is modulated to emit a second white light, wherein the second white light includes at least one broad-spectrum monochromatic light. The first white light and the second white light are mixed to produce a third white light. The color rendering index (CRI) of the third white light is greater than those of the first white light and the second white light, and the color coordinates of the first white light, the second white light, and the third white light are different from each other. Furthermore, an LED light source module and a package structure thereof are also provided.

Disclosed herein is a light fixture. The light fixture includes at least one first light source that emits at a peak wavelength in a range of approximately 380 nm to approximately 420 nm and at least one second light source that emits at a different peak wavelength, wherein a combined light output of the at least one first light source and the at least one second light source emits a colored light that is perceived as white light. The white light is defined by having a color rendering index (CRI) value of more than approximately 50. The at least one second light source that emits at a different peak wavelength consists of an xy coordinate on a International Commission on Illumination (CIE) 1931 xy color space diagram above a black body curve within a bounded area defined by a first line of approximately y=2.23989x−0.382773 and a second line of approximately y=1.1551x−0.195082. The combined light output has a proportion of spectral energy measured in the approximately 380 nm to approximately 420 nm range of greater than approximately 20%.

Disclosed herein is a light fixture. The light fixture includes at least one first light source that emits at a peak wavelength in a range of approximately 380 nm to approximately 420 nm and at least one second light source that emits at a different peak wavelength, wherein a combined light output of the at least one first light source and the at least one second light source emits a colored light that is perceived as white light. The white light is defined by having a color rendering index (CRI) value of more than approximately 50. The at least one second light source that emits at a different peak wavelength consists of an xy coordinate on a International Commission on Illumination (CIE) 1931 xy color space diagram above a black body curve within a bounded area defined by a first line of approximately y=2.23989x−0.382773 and a second line of approximately y=1.1551x−0.195082. The combined light output has a proportion of spectral energy measured in the approximately 380 nm to approximately 420 nm range of greater than approximately 20%.

The present invention relates to a system, method and tool for optimizing combination of Light Emitting Diodes (LEDs), and to an optimized combination of LEDs. The system and method provide a plurality of LEDs and corresponding specifications. Then, a color temperature and a color rendering index are selected. Calculations are performed for subgroups of LEDs. At least one optimized combination of LEDs having an optimized corresponding luminous flux is identified according to selected color temperature, color rendering index and LEDs' specifications. In another aspect, the present invention relates to a tool for optimizing white light generated by a combination of LEDs. The tool comprises a repository for storing specifications for the combination of LEDs, a selection module for selecting at least one of the following parameters: a color temperature, a color rendering index and a maximum shift variance from a black body locus, and a processing module for calculating for subgroups of LEDs resulting color temperature, color rendering index, luminous flux, and for identifying an optimized selection of LEDs. The present invention also relates to an optimized combination of LEDs for producing white light with high color rendering index, the combination of LEDs excluding blue LEDs.

The invention aims at providing controllable parameters that are correlated with special color rendering index R9, and at providing a white light-emitting semiconductor device having a high R9 value obtained through optimization of such parameters.The white light-emitting semiconductor device is provided with a phosphor as a light-emitting material and with a light-emitting semiconductor element as an excitation source of the phosphor. The phosphor includes at least a green phosphor and a wide-band red phosphor. In the white light-emitting semiconductor device, an intensity at wavelength 640 nm of an emission spectrum which has been normalized with respect to luminous flux is 100-110% of the intensity at wavelength 640 nm of a spectrum of standard light for color rendering evaluation which has been normalized with respect to luminous flux.