公开(公告)号：US20250116551A1

公开(公告)日：2025-04-10

申请号：US18834338

申请日：2023-01-27

Applicant: HAMAMATSU PHOTONICS K.K.

Inventor： Riku SHIMADA ,  Takuya FUJITA ,  Takashi BABA ,  Shunsuke ADACHI ,  Shinya IWASHINA

IPC: G01J1/44

Abstract: In a signal processing circuit, an input terminal is configured to receive an analog signal output from an avalanche photodiode operating in Geiger mode. A comparison circuit outputs a signal based on a component exceeding a threshold among components a signal input to the comparison circuit. The adjustment circuit includes an AC coupling unit, a level shifter unit, and a reference value adjustment unit. The AC coupling unit establishes AC coupling between the input terminal and the comparison circuit. The level shifter unit adjusts the voltage of the signal input to the comparison circuit to a value lower than a reverse bias voltage applied to the avalanche photodiode. The reference value adjustment unit adjusts the reference value of the signal input to the comparison circuit.