公开(公告)号：US20180109073A1

公开(公告)日：2018-04-19

申请号：US15570415

申请日：2016-04-28

Applicant: TOPCON CORPORATION

Inventor： Suguru MIYAGAWA ,  Yoshiaki GOTO ,  Yoshikatsu TOKUDA

IPC: H01S5/042 ,  H01S5/0683 ,  H01S3/00 ,  G01R15/22 ,  H04B10/50

CPC classification number: H01S5/042 ,  G01R15/22 ,  G01S7/484 ,  G01S7/497 ,  G01S17/10 ,  H01S3/0057 ,  H01S5/0057 ,  H01S5/0683 ,  H01S5/06835 ,  H01S5/06837 ,  H04B10/504

Abstract: Provided is a technology for suppressing variations in the waveform of a light emission pulse caused by various factors in a light-emitting device. A light-emitting device is provided with: a light source 101 in which relaxation oscillation occurs immediately after energization; a light source drive circuit 104 which includes a differentiation circuit 102 having a resistor and a capacitor connected in parallel, and in which a switching element 103 for voltage application is connected in series with the differentiation circuit; a power supply circuit 105; a light-reception element 107 which detects pulsed light emitted from the light source 101; and a voltage control unit 109 which controls an output voltage from the power supply circuit 105 in correspondence with the waveform of the detected pulsed light.