US 12,453,218 B2
Light-emitting device
Makiko Iwasa, Anan (JP); and Yuji Sato, Anan (JP)
Assigned to NICHIA CORPORATION, Anan (JP)
Appl. No. 17/907,354
Filed by NICHIA CORPORATION, Anan (JP)
PCT Filed Feb. 10, 2021, PCT No. PCT/JP2021/004900
§ 371(c)(1), (2) Date Sep. 26, 2022,
PCT Pub. No. WO2021/192681, PCT Pub. Date Sep. 30, 2021.
Claims priority of application No. 2020-058695 (JP), filed on Mar. 27, 2020.
Prior Publication US 2023/0109952 A1, Apr. 13, 2023
Int. Cl. H10H 20/851 (2025.01); H05B 33/14 (2006.01); H10H 20/01 (2025.01)
CPC H10H 20/8513 (2025.01) [H05B 33/14 (2013.01); H10H 20/0361 (2025.01)] 5 Claims
OG exemplary drawing
 
1. A light-emitting device, comprising
a light-emitting element that has a dominant wavelength in a range of 380 nm or more and 485 nm or less, and
a fluorescent material layer that comprises a fluorescent material emitting light by being excited by light emitted from the light-emitting element, and a neodymium compound,
the light-emitting device emitting light having a dominant wavelength in a range of 584 nm or more and 780 nm or less, and exhibiting a yellowish-red light emission color to red light emission color,
wherein the light-emitting device has a half value width in a light emission spectrum in a wavelength range of 584 nm or more and 780 nm or less being in a range of 50 nm or more and 100 nm or less,
wherein the fluorescent material comprises at least one nitride fluorescent material selected from the group consisting of a first nitride fluorescent material having a composition represented by the following formula (1), and a second nitride fluorescent material having a composition represented by the following formula (2):
(Ca,Sr)AlSiN3:Eu  (1)
(Ca,Sr,Ba)2Si5N8:Eu  (2)
wherein the fluorescent material layer has a content of the neodymium compound in a range of 5 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the fluorescent material.