US 12,117,136 B1
Vehicle lighting device and vehicle lamp
Daisuke Kosugi, Ehime-ken (JP)
Assigned to Toshiba Lighting & Technology Corporation, Kanagawa (JP)
Filed by Toshiba Lighting & Technology Corporation, Kanagawa (JP)
Filed on Mar. 7, 2024, as Appl. No. 18/599,081.
Claims priority of application No. 2023-107688 (JP), filed on Jun. 30, 2023; and application No. 2024-003417 (JP), filed on Jan. 12, 2024.
Int. Cl. F21S 41/19 (2018.01); F21S 41/143 (2018.01); H05B 47/105 (2020.01)
CPC F21S 41/192 (2018.01) [F21S 41/143 (2018.01); H05B 47/105 (2020.01)] 10 Claims
OG exemplary drawing
 
1. A vehicle lighting device, comprising:
a socket;
a substrate provided on one end side of the socket;
a light-emitting element provided on the substrate;
a control element provided on the substrate and comprising a current driver whose output side is electrically connected to the light-emitting element and a current setting circuit whose output side is electrically connected to the current driver;
a first circuit provided on the substrate, electrically connected to a first input side of the current setting circuit, and whose resistance value changes depending on an ambient temperature of the light-emitting element; and
a second circuit provided on the substrate, electrically connected to a second input side of the current setting circuit, and whose resistance value changes depending on the ambient temperature of the light-emitting element,
wherein the current setting circuit:
in a temperature region where the ambient temperature of the light-emitting element exceeds a first temperature and is equal to or lower than a second temperature higher than the first temperature, decreases an output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises, based on changes in the resistance value of the first circuit, and
in a temperature region where the ambient temperature of the light-emitting element exceeds the second temperature, increases a ratio of decreasing the output current flowing to the light-emitting element as the ambient temperature of the light-emitting element rises, based on changes in the resistance value of the second circuit.