发明名称 Pixel circuit with capacitor discharge indicative of number of events
摘要 A pixel circuit includes a single photon avalanche diode (SPAD) and a measurement circuit including a capacitance. The circuit is operable to discharge a known portion of the charge on the capacitance upon each detection of a SPAD event within a time period, such that the charge remaining on the capacitance at the end of the time period corresponds to the number of SPAD events detected within the time period. A time resolved imaging apparatus includes an array of such pixel circuits. A method of counting photon detection includes sensing photons with a SPAD device and discharging a known portion of the charge on a capacitance upon each detection of a SPAD event within a time period.
申请公布号 US9313434(B2) 申请公布日期 2016.04.12
申请号 US201314066853 申请日期 2013.10.30
申请人 STMicroelectronics (Research & Development) Limited 发明人 Dutton Neale;Henderson Robert Kerr
分类号 H01L31/107;H04N5/3745;G01S17/89;G01S7/486 主分类号 H01L31/107
代理机构 Gardere Wynne Sewell LLP 代理人 Gardere Wynne Sewell LLP
主权项 1. A pixel circuit, comprising: a single photon avalanche diode (SPAD) configured to detect SPAD events; a measurement circuit comprising a capacitance, wherein said measurement circuit is operable to discharge a portion of the charge on said capacitance upon each SPAD event detection within a time period, such that the charge remaining on said capacitance at the end of the time period corresponds to the number of SPAD events detected within the time period; and a time gating stage operable to begin sensing operation on reception of an enable signal and comprising: a switch operable to selectively connect the SPAD output to the measurement circuit on reception of said enable signal; andtwo further switches operable to disable the pixel circuit on reception of a disable signal.
地址 Marlow GB