259results about How to "Good color properties" patented technology

A light emitting device that emits light of various colors by blending lights emitted by two or more kinds of fluorescent materials which are substantially directly excited by the light emitted by an excitation source having principal emission peak in a range from 250 nm to 500 nm. Each of the fluorescent material is of a direct-transition type.

A phosphor that emits white light due to excitation by a light emitting diode capable of emitting blue or ultraviolet light includes: a substrate that allows transmission of visible light; and a semiconductor layer formed on the substrate.

A semiconductor light emitting device of the present invention includes four elements provided on a substrate and having different light emitting colors of red, green, blue, and white, respectively; a resin covering each of the elements; and a reflector provided to surround a circumference of the resin. With this structure, a semiconductor light emitting device having high brightness and excellent color rendering properties can be provided.

By using a light emitting device including an insulating substrate and a light emitting unit formed on the insulating substrate, the light emitting unit including: a plurality of linear wiring patterns disposed on the insulating substrate in parallel with one another, a plurality of light emitting elements that are mounted between the wiring patterns while being electrically connected to the wiring patterns, and a sealing member for sealing the light emitting elements, as well as a method for manufacturing thereof, it becomes possible to provide a light emitting device that achieves sufficient electrical insulation and has simple manufacturing processes so that it can be manufactured at a low cost, and a method for manufacturing the same.

To provide a light emitting device having a phosphor mixture and a light emitting part, the phosphor mixture including a red phosphor and more than one kind of phosphor having an emission spectrum with a peak in a wavelength range from 500 nm to 630 nm, and emitting light having a sufficient luminance and excellent in color rendering properties not only in a white light with high correlated color temperature, but also in a warm white light with low correlated color temperature. CaAlSiN₃:Eu manufactured as a red phosphor and and CaAl₂Si₄N₈:Eu manufactured as an orange phosphor, and for example, commercial YAG:Ce as a yellow-green phosphor, are prepared, and emission spectra of these phosphors are measured when excited by excitation light in the wavelength range from 430 nm to 500 nm. Further, the emission spectrum of the light used as an excitation light are measured, by simulation using their emission spectra, a mixing ratio of each phosphor, by which the correlated color temperature of the phosphor mixture becomes a target color temperature, is obtained. And based on the result of the simulation, each phosphor is measured nad mixed, thus obtaining the phosphor mixture.

To provide a phosphor containing a comparatively much red component and having high light emitting efficiency, high brightness and further high durability, the nitride phosphor is represented by the general formula L_XM_YN_{((2/3)X+(4/3)Y)}:R or L_XM_YO_ZN_{((2/3)X+(4/3)Y−(2/3)Z)}:R (wherein L is at least one or more selected from the Group II Elements consisting of Mg, Ca, Sr, Ba and Zn, M is at least one or more selected from the Group IV Elements in which Si is essential among C, Si and Ge, and R is at least one or more selected from the rare earth elements in which Eu is essential among Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Lu.); contains the another elements.

Provided is a radiation-sensitive colored composition that enables formation of color cured films in which color concentration unevenness is inhibited and which have uniform color and exhibit a superior development property and excellent pattern formability in the formation of color patterns.

The radiation-sensitive colored composition contains (A) a dye polymer containing a structural unit having a dye structure polymerized using a chain-transfer agent having a LogP value of 5 or less, and (B) a solvent.

A light-emitting device (1) is composed by integrating light-emitting diodes (2R, 2G, 2B) and a drive IC (3) for driving these light-emitting diodes (2R, 2G, 2B). The light-emitting device (1) is characterized in that the drive IC (3) has a built-in circuit for controlling the current value of each light-emitting diode (2) or the current proportions of the light-emitting diodes at constant values. The adjustment of the intensities of the light beams emitted from the light-emitting diodes can be simplified, and no outside circuits for adjustment are needed. The structure is excellent in assemblability. When a desired emission color is produced by mixing the emission colors, the adjustment for the mixing is easy, and a structure suited for enhancing the color rendering properties when a while light is emitted is provided.

Conventional light emitting diode designs combined with blue light emitting diodes tend to lack in decorativeness and warmness. The present invention aims at providing a white light emitting diode for emitting white light with warmness at a higher luminance, and an intermediate color light emitting diode satisfying light emission in diversified color tones at a higher luminance.

The solving means resides in adoption of a fluorescent material which is configured to emit yellowish red or red light and which comprises a CaAlSiN₃ crystal phase including, dissolved therein in a solid state, one kind or two or more kinds of element(s) selected from Mn, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, in a manner that the fluorescent material is mixed with another fluorescent material configured to emit green, yellowish green, or yellow light, and that the mixedly obtained phosphor is combined with a semiconductor light emitting element configured to emit bluish purple or blue light, to thereby fabricate a white light emitting diode for emitting white light with warmness at a high efficiency.

A light-emitting device includes a light-emitting element emitting primary light and a wavelength conversion portion absorbing a part of the primary light and emitting secondary light having a wavelength equal to or longer than the wavelength of the primary light. The wavelength conversion portion includes a plurality of green or yellow light-emitting phosphors and a plurality of red light-emitting phosphors. The green or yellow light-emitting phosphor is implemented by at least one selected from a specific europium (II)-activated silicate phosphor (A-1) and a specific cerium (III)-activated silicate phosphor (A-2). The red light-emitting phosphor is implemented by a specific europium (II)-activated nitride phosphor (B). The light-emitting device emitting white light at efficiency and color rendering property higher than in a conventional example can thus be provided.

A medical lighting apparatus includes single or plural LED units. Each of the LED units comprises a plurality of concave reflecting surfaces and an LED element disposed in front of each of the reflecting surface so as to radiate light toward each of the reflecting surfaces. Each of the LED units is arranged so that the lights radiated from its LED elements are reflected by the reflecting surfaces, emerge outside and are superimposed on one another on an area to be illuminated, respectively, while illuminating the area. The LED elements of each of the LED units comprise a combination of different emitting colors so as to enhance the color rendering properties.

A white organic electroluminescent device (1) including an emitting layer (5, 6 and 7) interposed between an anode (2) and a cathode (9), the emitting layer (5, 6 and 7) emitting blue light, green light and red light, the emitting layer (6) containing a green dopant that is an aromatic amine compound represented by formula (1),

wherein A¹, A² and R¹² are a hydrogen atom, an alkyl group, an aryl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an arylamino group, an alkylamino group or a halogen atom; d and e are independently 1 to 5; h is 1 to 9; R¹¹ is a secondary or tertiary alkyl or cycloalkyl group; f is 1 to 9; g is 0 to 8 and f+g+h is 2 to 10.

A headlamp (1) includes a laser diode (2) for emitting a laser beam and a light-emitting section (5), which contains a fluorescent substance for emitting fluorescence upon receiving the laser beam emitted from the laser diode (2) and diffusing particles (15) for diffusing the laser beam.

A vehicle light can include a light emitting diode (LED) serving as a light source and an optical system for controlling a light distribution pattern of the light beams from the LED light source utilizing a light guide (such as a lens body having an inner reflecting surface). The vehicle light can project illumination light with a low beam light distribution pattern. The vehicle light can include an LED light source and a lens body serving as a light guide. The lens body can include a light incident surface, a reflecting surface, and a light exiting surface. The LED light source can have a rearmost end light emitting point from which light beams are emitted to form a bright-dark boundary line. Among the light beams, perpendicularly incident light beams not subjected to refraction can be projected toward the bright-dark boundary line while obliquely incident light beams that are subjected to refraction can be corrected to be directed in a lower angular direction than the bright-dark boundary line and to be mixed with the other light beams, thereby preventing color shading of illumination light from the vehicle light.

An object of the present invention is to provide a light emitting apparatus that allows it to easily control the driving of LED and has high color rendering properties.

The light emitting apparatus comprises the first light emitting device 108a that has first peak emission wavelength in blue region and emits blue light, the fluorescent material 140 that is excited by the light from the first light emitting device 108a and emits red light, the second light emitting device 108b that has second peak emission wavelength which is longer than the first peak emission wavelength and is shorter than peak emission wavelength of the fluorescent material 140, and the second light emitting device 108b that emits green light of second peak emission wavelength which is longer than the first peak emission wavelength, so as to emit light generated by blending of blue light, green light and red light to the outside.

To provide a phosphor having an emission spectrum with a broad peak in a range from green color to yellow color, having a broad and flat excitation band capable of using lights of broad range from near ultraviolet/ultraviolet to blue lights as excitation lights, and having excellent emission efficiency and luminance. The problem is solved by providing the phosphor expressed by a general composition formula MmAaBbOoNn:Z (where element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kinds of elements acting as the activator.), satisfying 4.0<(a+b)/m<7.0, a/m=0.5, b/a>2.5, n>o, n=2/3m+a+4/3b−2/3o, and having an emission spectrum with a peak wavelength of 500 nm to 650 nm when excited by light in a wavelength range from 300 nm to 500 nm.