US 12,140,305 B2
Light-emitting device, electronic device, and method for using light-emitting device
Mitsuru Nitta, Kyoto (JP); Shozo Oshio, Osaka (JP); and Takeshi Abe, Osaka (JP)
Assigned to Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Mar. 7, 2024, as Appl. No. 18/598,177.
Application 18/598,177 is a continuation of application No. 17/418,278, granted, now 11,959,632, previously published as PCT/JP2019/049558, filed on Dec. 18, 2019.
Claims priority of application No. 2018-245494 (JP), filed on Dec. 27, 2018.
Prior Publication US 2024/0247781 A1, Jul. 25, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. F21V 9/30 (2018.01); A61B 5/00 (2006.01); A61N 5/06 (2006.01); A61N 5/067 (2006.01); A61B 1/04 (2006.01); A61B 1/06 (2006.01); F21W 131/20 (2006.01); F21Y 115/30 (2016.01)
CPC F21V 9/30 (2018.02) [A61B 5/0071 (2013.01); A61N 5/062 (2013.01); A61N 5/067 (2021.08); A61B 1/043 (2013.01); A61B 1/0653 (2013.01); F21W 2131/20 (2013.01); F21Y 2115/30 (2016.08)] 17 Claims
OG exemplary drawing
 
1. A light-emitting device comprising:
a light source that radiates a primary light; and
a first phosphor that absorbs the primary light and converts the primary light into a first wavelength-converted light having a longer wavelength than the primary light, wherein:
the first wavelength-converted light includes fluorescence based on electron energy transition of Cr3+, the fluorescence having an afterglow of more than 10 μs based on a parity-forbidden transition,
a fluorescence spectrum of the first wavelength-converted light has a maximum fluorescence intensity value in region of a wavelength exceeding 710 nm, and
the light source is a solid-state light-emitting element with a rated light output of 1 W or more, wherein saturation of the fluorescence based on the parity-forbidden transition of Cr3+ is less likely to occur under excitation by the primary light relative to saturation of fluorescence based on a parity-allowed transition of Ce3+ or Eu2+ having an afterglow of 10 μs or less.