A wavelength conversion device includes a wavelength conversion plate, a reflective layer, a driving component and a thermal conductive layer. The wavelength conversion plate includes a lateral edge, at least one surface and a conversion region. The reflective layer is disposed on the surface of the wavelength conversion plate. The driving component is disposed near the lateral edge of the wavelength conversion plate and configured to displace the wavelength conversion plate. The thermal conductive layer is disposed on the surface of the wavelength conversion plate and thermally connected to the conversion region for conducting heat generated by the conversion region during a wavelength conversion. By disposing the thermal conductive layer on the surface of the wavelength conversion plate, the thermal conductive layer is thermally directly connected to the conversion region, so that the heat generated at the conversion region during the wavelength conversion is efficiently dissipated.

A photoelectric conversion compound is provided. The photoelectric conversion compound has a structure represented by formula (I):

##STR00001##

wherein D represents an inorganic luminescent group; each of R.sup.1, R.sup.2, and R.sup.3 independently represents a hydrogen atom or a C.sub.1-6 alkyl group; R.sup.4 represents a single bond or a C.sub.1-6 alkylene group; m represents an integer of 1-10; k represents an integer of 1-1,000; and n represents an integer of 1-10,000.

A lighting apparatus includes light emitting elements having an emission peak wavelength of 400 to 510 nm, a first phosphor having an emission peak wavelength of 485 to 700 nm, a second phosphor having an emission peak wavelength of 510 to 590 nm, a third phosphor having an emission peak wavelength of 600 to 700 nm, and a color filter having transmittance for light with a wavelength of 600 to 730 nm that is 80% or more and transmittance for light with a wavelength of 410 to 480 nm that is 3% or more and 50% or less. The color filter transmits a part of light emitted from the first phosphor, at least a part of light emitted from the second phosphor, and at least a part of light emitted from the third phosphor. Light transmitted through the color filter is emitted to the outside.

A light-emitting ceramic that includes a pyrochlore type compound that contains 0.01 mol % or more of Bi with respect to 100 mol % of the general formula M1.sub.XM2.sub.YM3.sub.ZO.sub.W, wherein M1 is at least one of La, Y, Gd, Yb, and Lu, M2 is at least one of Zr, Sn, and Hf, M3 is at least one of Ta, Nb, and Sb, X, Y, Z, and W are positive numbers that maintain electrical neutrality, X+Y+Z=2.0, 0.005≤Z≤0.2, and 3X+4Y+5Z is 7.02 or less.

In an embodiment a conversion element includes a first phase and a second phase, wherein the first phase comprises lutetium, aluminum, oxygen and a rare-earth element, wherein the second phase comprises Al.sub.2O.sub.3 single crystals, and wherein the conversion element comprises at least one groove.

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° 2θ or more and 19° 2θ or less and a second peak in a range of 34° 2θ or more and 35.5° 2θ or less in a CuKα powder X-ray diffraction pattern.

A light emitting diode package includes: a housing; a light emitting diode chip arranged in the housing; a wavelength conversion unit arranged on the light emitting diode chip; a first fluorescent substance distributed inside the wavelength conversion unit and emitting light having a peak wavelength in the cyan wavelength band; and a second fluorescent substance distributed inside the wavelength conversion unit and emitting light having a peak wavelength in the red wavelength band, wherein the peak wavelength of light emitted from the light emitting diode chip is located within a range of 415 nm to 430 nm.

A phosphor combination may include a first phosphor and a second phosphor. The second phosphor may be a red-emitting quantum dot phosphor. The phosphor combination may optionally include a third phosphor that is a red-emitting phosphor with the formula (MB) (TA)3-2x(TC)1+2xO4-4xN4x:E. A conversion element may include the phosphor combination. An optoelectronic device may include the phosphor combination and a radiation-emitting semiconductor chip.

The invention relates to a phosphor with garnet structure and a light-emitting device comprising the phosphor, wherein the phosphor includes the following components in percentage by weight: 38.47-45.19% of Y element, 9.49-22.09% of Al element, 2.06-24.31% of Ga element, 27.3-32.04% of O element, 0.43-1.46% of Ce element. In the phosphor particles, the shortest distance from the surface of one side of the particle to the surface of the opposite side through the centroid of the particle is defined as R, the longest distance is R1, and 5 μm≤R≤40 μm; any distance from the particle surface to the centroid is r, and 0<r<½R; and the space with the distance from the particle surface to the centroid direction being less than or equal to r is defined as r.sub.inner.

A wavelength converting structure is disclosed, the wavelength converting structure including an SWIR phosphor material having emission wavelengths in the range of 1000 to 1700 nm, the SWIR phosphor material including at least one of a perovskite type phosphor doped with Ni.sup.2+, a perovskite type phosphor doped with Ni.sup.2+ and Cr.sup.3+, and a garnet type phosphor doped with Ni.sup.2+ and Cr.sup.3+.