Provided is a ceramic complex having high luminous characteristics. Proposed is a ceramic complex including a rare earth aluminate fluorescent material, glass, and calcium fluoride, wherein, when the total amount of the rare earth aluminate fluorescent material, the glass, and the calcium fluoride is taken as 100% by volume, the content of the rare earth aluminate fluorescent material is in a range of 15% by volume or more and 60% by volume or less, the content of the glass is in a range of 3% by volume or more and 84% by volume or less, and the content of the calcium fluoride is in a range of 1% by volume or more and 60% by volume of less.

A method for producing a ceramic composite includes: preparing a sintered body in a plate form containing a fluorescent material having a composition of a rare earth aluminate, and aluminum oxide; and eluting the aluminum oxide from the sintered body by contacting the sintered body with a basic substance, for example, contained in an alkali aqueous solution, and the dissolution amount of the fluorescent material eluted from the sintered body in the step of eluting the aluminum oxide is 0.5% by mass or less based on an amount of the fluorescent material contained in the sintered body as 100% by mass.

Light emitting devices and LED-filaments comprise an excitation source (e.g. LED) and a photoluminescence material comprising a combination of a first narrow-band red photoluminescence material which generates light with a peak emission wavelength in a range 580 nm to 628 nm and a full width at half maximum emission intensity in a range 45 nm to 60 nm and a second narrow-band red photoluminescence material generates light with a peak emission wavelength in a range 628 nm to 640 nm and a full width at half maximum emission intensity in a range 5 nm to 20 nm. At least one of the first and second narrow-band red photoluminescence materials can comprise a narrow-band red phosphor or a quantum dot (QD) material.

A lighting device including at least one light emitter to emit blue light, a green phosphor having an emission peak in a range of 500 nm to 550 nm, a yellow phosphor having an emission peak in a range of 550 nm to 600 nm, and a red phosphor having an emission peak in a range of 600 nm to 650 nm, in which the yellow phosphor and the red phosphor have different full widths at half maximum, and the full width at half maximum of the yellow phosphor is longer than that of the red phosphor, and, in an emission spectrum, an intensity of light emitted from the lighting device increases from 500 nm to 600 nm, and the intensity of light emitted from the lighting device at 700 nm is less than about 10% of the maximum intensity of light emitted from the lighting device.

Provided is a method including: preparing a substrate having a first surface; preparing a wavelength conversion layer that converts a light of a first wavelength band into a light of a second wavelength band different from the light of the first wavelength band; preparing a bonding material including a metal fine particle and a surface stabilizer formed at a surface of the metal fine particle and decomposed by oxygen; forming a protective film protecting the first surface while the protective film generates a gas containing hydrogen; releasing, from one of the protective film and the substrate, the gas occluded by the one of the protective film and the substrate in the forming of the protective film; and bonding the substrate and the wavelength conversion layer via the bonding material by metal sintering.

A light emitting device comprises a light emitting element having a light emission peak wavelength in a range of 400 nm or more and 490 nm or less and a first fluorescent material having a light emission peak wavelength in a range of 570 nm or more and 680 nm or less, and emits light having a correlated color temperature being 1,950 K or less, an average color rendering index Ra being 51 or more, a full width at half maximum of a light emission peak having a maximum light emission intensity in a light emission spectrum of the light emitting device being 110 nm or less, and a first glare index Ls1/L that is a ratio of a first effective radiance Ls1 to a luminance L being 0.493 or less, wherein Ls1 and L are as defined in the disclosure.

Provided is a method for producing a wavelength conversion sintered body that emits light under irradiation of excitation light. The method for producing a wavelength conversion sintered body includes: preparing a molded body obtained by molding a mixture containing an α-SiAlON fluorescent material and aluminum oxide particles and having a content of Ga of 15 ppm by mass or less; and primary calcining the molded body at a temperature in a range of 1,370° C. or more and 1,600° C. or less to obtain a first sintered body.

A light generating system (1000) comprising a plurality of light sources (10) configured to provide light source light (11), an elongated luminescent body (100) having a first face (141) and a second face (142) defining a length (L) of the elongated luminescent body (100), the elongated luminescent body comprising one or more side faces (140), the elongated luminescent body (100) comprising a radiation input face (111) and the second face (142) comprising a first radiation exit window (112), wherein the radiation input face (111) is configured in a light receiving relationship with the plurality of light sources (10), wherein the elongated lumines-cent body (100) comprises luminescent material (120) configured to convert at least part of the light source light (11) into luminescent material light (8), and a beam shaping optical element (224).

A light emitting device comprises a light emitting element having a light emission peak wavelength in a range of 400 nm or more and 490 nm or less and a first fluorescent material having a light emission peak wavelength in a range of 570 nm or more and 680 nm or less, and emits light having a correlated color temperature being 1,950 K or less, an average color rendering index Ra being 70 or more, a full width at half maximum of a light emission peak having the maximum light emission intensity being 110 nm or less, and a ratio B/L of an effective radiance B to a luminance L being 0.151 or less, wherein the luminance of light emitted by the light emitting device in a range of 300 nm or more and 800 nm or less when B and L is as defined in the disclosure.

An LED pump light with multiple phosphors is described. LEDs emitting radiation at violet and/or ultraviolet wavelengths are used to pump phosphor materials that emit other colors. The LEDs operating in different wavelength ranges are arranged to reduce light re-absorption and improve light output efficiency.