US 12,235,155 B2
Photon detection system including an avalanche photodiode and a biasing circuit to supply a gating signal
Mirko Sanzaro, Cambridge (GB); Christopher Meayers, Cambridge (GB); James F. Dynes, Cambridge (GB); Andrew Simpkins, Cambridge (GB); and Andrew James Shields, Cambridge (GB)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (JP)
Filed by Kabushiki Kaisha Toshiba, Tokyo (JP)
Filed on Feb. 28, 2023, as Appl. No. 18/175,618.
Claims priority of application No. 2213116 (GB), filed on Sep. 8, 2022.
Prior Publication US 2024/0085240 A1, Mar. 14, 2024
Int. Cl. G01J 1/44 (2006.01)
CPC G01J 1/44 (2013.01) [G01J 2001/4466 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A photon detection system, comprising:
an avalanche photodiode configured to generate a photodiode signal in response to an incident photon;
a biasing circuit configured to supply a gating signal to the avalanche photodiode, wherein the gating signal is a periodic signal configured to reverse bias the avalanche photodiode above and below a breakdown voltage for photon detection of the avalanche photodiode during each period;
a transmission line configured to receive the photodiode signal and to provide the photodiode signal to a non-reflective filter circuit, and
the non-reflective filter circuit configured to:
receive, at an input port, the photodiode signal from the transmission line, and
provide, at a first output port, a first filtered output signal by applying a low-pass filter with a first cut-off frequency to the received photodiode signal,
wherein the input port of the non-reflective filter circuit is configured to be impedance matched to the transmission line up to a frequency higher than a gate frequency of the gating signal.