US Patent No. 10,560,991

LIGHT EMITTING DEVICE


Patent No. 10,560,991
Issue Date February 11, 2020
Title Light Emitting Device
Inventorship Terumitsu Sugimoto, Makinohara (JP)
Koji Ikegaya, Makinohara (JP)
Assignee YAZAKI CORPORATION, Minato-ku, Tokyo (JP)

Claim of US Patent No. 10,560,991

1. A light emitting device comprising:a plurality of light source units including:
a light source board on which a plurality of types of light sources to be connected to each other in parallel is mounted;
a constant current board on which a constant current circuit for supplying current to the light source is mounted; and
a housing for housing the light source board and the constant current board,
wherein the light sources of the same type of the plurality of the light source units are connected in series to each other,
wherein colors of lights emitted by the light sources are different for each of the types,
wherein a plurality of constant current circuits are connected in series with each type of the light sources, and are disposed dispersedly on the constant current boards of the plurality of light source units,
wherein two light source units are provided,
wherein the light source board is provided with the light sources of three types,
wherein the constant current circuits for each supplying current to the light sources of two types are mounted on one constant current board of the two light source units, each drive current for the light sources of the two types is smaller among the light sources of three types, and
wherein the constant current circuit for supplying current to the light source of one type is mounted on the other constant current board of the two light source units, the drive current of the light source of the one type is the largest among the light sources of the three types.