C09K11/7739

Light emitting device
10559725 · 2020-02-11 · ·

A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440 nm and a phosphor member. The phosphor member includes a first phosphor having a peak emission wavelength of 430 nm to 500 nm and containing an alkaline-earth phosphate, a second phosphor having a peak emission wavelength of 440 nm to 550 nm and containing at least one of an alkaline-earth aluminate and a silicate containing Ca, Mg, and Cl, a third phosphor having a peak emission wavelength of 500 nm to 600 nm and containing a rare-earth aluminate, a fourth phosphor having a peak emission wavelength of 610 nm to 650 nm and containing a silicon nitride containing Al and at least one of Sr and Ca, and a fifth phosphor having a peak emission wavelength of 650 nm to 670 nm and containing a fluorogermanate.

LIGHT EMITTING DEVICE

To provide a semiconductor light emitting device which is capable of accomplishing a broad color reproducibility for an entire image without losing brightness of the entire image. A light source provided on a backlight for a color image display device has a semiconductor light emitting device comprising a solid light emitting device to emit light in a blue or deep blue region or in an ultraviolet region and phosphors, in combination. The phosphors comprise a green emitting phosphor and a red emitting phosphor. The green emitting phosphor and the red emitting phosphor are ones, of which the rate of change of the emission peak intensity at 100? C. to the emission intensity at 25? C., when the wavelength of the excitation light is 400 nm or 455 nm, is at most 40%.

OXIDE FLUORESCENT MATERIAL, LIGHT EMITTING DEVICE, AND METHOD FOR PRODUCING OXIDE FLUORESCENT MATERIAL
20240052240 · 2024-02-15 · ·

Provided is an oxide fluorescent material having a light emission peak in a wavelength range from red light to near-infrared light.

The oxide fluorescent material has a composition including: a first element M.sup.1 being at least one element selected from the group consisting of Li, Na, K, Rb, and Cs; a second element M.sup.2 being at least one element selected from the group consisting of Ca, Sr, Mg, Ba, and Zn; Ge; O (oxygen); and Cr, the composition optionally including: a third element M.sup.3 being at least one element selected from the group consisting of Si, Ti, Zr, Sn, Hf, and Pb; and a fourth element M.sup.4 being at least one element selected from the group consisting of Eu, Ce, Tb, Pr, Nd, Sm, Yb, Ho, Er, Tm, Ni, and Mn. When the molar ratio of Ge, or the total molar ratio of the third element M.sup.3 and Ge in the case of comprising the third element M.sup.3, in 1 mol of the composition of the oxide fluorescent material is 6, the molar ratio of the first element M.sup.1 is 1.5 or more and 2.5 or less, the molar ratio of the second element M.sup.2 is 0.7 or more and 1.3 or less, the molar ratio of the third element M.sup.3 is 0 or more and 0.4 or less, the molar ratio of O (oxygen) is 12.9 or more and 15.1 or less, and the molar ratio of Cr is 0.2 or less. The oxide fluorescent material has a light emission peak wavelength of 700 nm or more and 1,050 nm or less in a light emission spectrum of the oxide fluorescent material.

White light emitting device, light bar and light apparatus

A white light emitting device, a light bar and a light apparatus. A relative spectrum of the white light emitting device is (). A relative spectrum of a black body radiation with a corresponding color temperature is S(). An area normalization is performed on () and S() to convert an equal energy spectrum () of the white light emitting device and an equal energy spectrum S() of the black body radiation with the corresponding color temperature. A degree of similarity R of the equal energy spectrum of the white light emitting device and the equal energy spectrum of the black body radiation satisfies the following formula: R = 1 - i n .Math. S ( ) - ( ) .Math. i n S ( ) ,
when i is 380 nm, n is 680 nm, R85%.

Nitride phosphor, method for manufacturing the same, and light emitting device

A nitride phosphor having a composition containing Eu, Si, Al, N, and a group 2 element including at least one selected from the group consisting of Mg, Ca, Sr, and Ba. In the composition, a ratio of a total molar content of the group 2 element and Eu to a molar content of Al is 0.8 or more and 1.1 or less, a molar ratio of Eu is 0.002 or more and 0.08 or less, a molar ratio of Si is 0.8 or more and 1.2 or less, and a total molar ratio of Si and Al is 1.8 or more and 2.2 or less. The nitride phosphor has a first peak in a range of 17 2 or more and 19 2 or less and a second peak in a range of 34 2 or more and 35.5 2 or less in a CuK powder X-ray diffraction pattern.

Method for manufacturing light-emitting device
10493175 · 2019-12-03 · ·

A light-emitting device includes a light-emitting element with a peak emission wavelength in a range of 400 nm to 410 nm and a fluorescent member that contains a first phosphor with a peak emission wavelength in a range of 440 nm to 470 nm containing a Eu-activated alkaline-earth phosphate that contains Cl in a composition, a second phosphor with a peak emission wavelength in a range of 500 nm to 530 nm containing a Eu-activated halogen-containing alkaline-earth silicate, a third phosphor with a peak emission wavelength in a range of 530 nm to 600 nm containing a Ce-activated rare-earth aluminate, and a fourth phosphor with a peak emission wavelength in a range of 600 nm to 660 nm containing a Eu-activated silicon nitride containing Al and at least one of Sr and Ca in a composition.

Blue-emitting phosphors and methods of use thereof

Provided herein are phosphors of the general molecular formula:
(A.sub.2-2xEu.sub.x)(Mg.sub.1-yCa.sub.y)PO.sub.4F
wherein the variables are as defined herein. Methods of producing the phosphors are also provided. In some aspects, the present disclosure provides light-emitting devices comprising these phosphors.

Phosphor

A phosphor is represented by the general formula
aM.sup.IX.Math.M.sup.II.sub.1-xM.sup.IM.sup.VO.sub.4:(Re).sub.x
where M.sup.I is at least one atomic element selected from the group consisting of K, Li, Na, Rb, Cs, Fr, Cu, and Ag, with K being essential; M.sup.II is at least one atomic element selected from the group consisting of Mg, Ca, Sr, Ba, Ra, Mn, Zn, Cd, and Sn; M.sup.V is at least one atomic element selected from the group consisting of P, V, Nb, Ta, As, Sb, and Bi; X is at least one halogen element, with F being essential; Re is at least one atomic element selected from the group consisting of rare earth elements, with Eu being essential; and a is in the range 0.6a1.4.

PHOSPHOR AND PRODUCTION METHOD THEREOF, AND LIGHT-EMITTING DEVICE

A phosphor according to an embodiment is a europium-activated alkaline-earth chloroapatite phosphor having a composition expressed by a composition formula: (M.sub.1-xEu.sub.x).sub.5(PO.sub.4).sub.3Cl, where M is an alkaline-earth element containing at least Sr and Ba, x is an atomic ratio satisfying 0.04x0.2. In the phosphor of this embodiment, absorptance of light at a wavelength of 400 nm is 90% or more, and absorptance of light at a wavelength of 650 nm is 2% or less.

Light emitting device and LED light bulb

A light emitting device includes: a first white light source which includes N pieces of first white light emitting diodes and emits a first white light; and a second white light source which includes M pieces of second white light emitting diodes and a first resistance element electrically connected in series to the second white light emitting diodes and having a first resistance value, is electrically connected in parallel to the first white light source, and emits a second white light, the light emitting device emitting a mixed white light of the first white light and the second white light. The drive voltage of the first white light source is higher than a drive voltage of the second white light source, and a color temperature of the mixed white light is higher as a total luminous flux of the mixed white light is higher.