公开(公告)号：US09939535B2

公开(公告)日：2018-04-10

申请号：US15027765

申请日：2014-09-26

Applicant: WASEDA UNIVERSITY ,  HAMAMATSU PHOTONICS K.K.

Inventor： Jun Kataoka ,  Toru Nishiyama ,  Shinji Ohsuka ,  Michito Hirayanagi ,  Shunsuke Adachi ,  Tetsuya Uchiyama

IPC: G01T1/24 ,  G01T1/20

CPC classification number: G01T1/244 ,  G01T1/2018 ,  G01T1/2921

Abstract: A Compton camera includes a scattering detection unit, an absorption detection unit, a signal processing unit, a first shield unit, and a second shield unit. The scattering detection unit detects Compton scattering of incident radiation emitted from a radiation source. The absorption detection unit detects absorption of incident radiation that has undergone Compton scattering at the scattering detection unit. The signal processing unit obtains an image of the radiation source based on coincident detection events of Compton scattering of radiation at the scattering detection unit and absorption of radiation at the absorption detection unit. The first and second shield units are provided between the scattering detection unit and the absorption detection unit. The first shield unit selectively allows forward-scattered radiation to pass and selectively blocks back-scattered radiation.

公开(公告)号：US09989657B2

公开(公告)日：2018-06-05

申请号：US15335588

申请日：2016-10-27

Applicant: HAMAMATSU PHOTONICS K.K.

Inventor： Shigeyuki Nakamura ,  Tsuyoshi Ohta ,  Michito Hirayanagi ,  Hiroki Suzuki ,  Shunsuke Adachi

IPC: G01T1/24 ,  G01T1/18 ,  H01L31/02

CPC classification number: G01T1/247 ,  G01T1/18 ,  H01L31/02027

Abstract: A readout circuit for reading out an output current from a photoelectric conversion element which collectively outputs currents generated in a plurality of pixels, each of which includes an avalanche photodiode, includes a current mirror circuit configured to receive the output current and output first and second currents having magnitudes in proportion to the output current, a photon counting circuit configured to count the number of photons incident on the photoelectric conversion element on the basis of the first current, an integral circuit configured to integrate the second current to generate a voltage signal, and a signal processing unit configured to determine a magnitude of light incident on the photoelectric conversion element on the basis of a counting result output from the photon counting circuit and a magnitude of the voltage signal output from the integral circuit.