US 12,149,046 B2
Light emission drive circuit and light emission device
Hayato Kamizuru, Kagoshima (JP); Katsuhisa Daio, Kagoshima (JP); and Hiroyuki Shoubu, Kagoshima (JP)
Assigned to Sony Semiconductor Solutions Corporation, Kanagawa (JP)
Appl. No. 17/294,220
Filed by Sony Semiconductor Solutions Corporation, Kanagawa (JP)
PCT Filed Nov. 19, 2019, PCT No. PCT/JP2019/045253
§ 371(c)(1), (2) Date May 14, 2021,
PCT Pub. No. WO2020/129521, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 2018-236893 (JP), filed on Dec. 19, 2018.
Prior Publication US 2022/0013981 A1, Jan. 13, 2022
Int. Cl. H01S 5/042 (2006.01); G01S 17/89 (2020.01)
CPC H01S 5/0427 (2013.01) [G01S 17/89 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A light emission drive circuit comprising:
a light emission current wire configured to flow a light emission current for causing a light emitting element to emit light, in the light emitting element;
a light emission current switch that is connected to the light emission current wire, and is configured to control the light emission current;
a preliminary current wire configured to flow, in the light emission current wire, a preliminary current for exciting an inductance component of the light emission current wire before a light emission period being a period in which the light emission current flows in the light emitting element;
a preliminary current switch that is connected to the preliminary current wire, and is configured to control the preliminary current; and
a bias circuit configured to supply a current substantially equal to a light emission threshold of the light emitting element, to the light emitting element as a bias current,
wherein the light emitting element includes
a light emission chip that includes two electrodes arranged therein, and is configured to emit light in accordance with the light emission current flowing between the two electrodes,
two light emission current terminals for flowing the light emission current that are respectively arranged for the two electrodes, and
a preliminary current terminal for flowing the preliminary current that is arranged on at least one of the two electrodes, and wherein
the light emission current wire is connected to at least one of the two light emission current terminals, and
the preliminary current wire is connected to the preliminary current terminal.