This article reports the design and characterization of a 32 $\times $ 32 single-photon avalanche diode (SPAD) time-resolved image sensor for quantum imaging applications fabricated in a 150-nm CMOS standard technology. A per-SPAD time-to-digital converter (TDC) records the spatial cross correlation functions of a flux of entangled photons. Each 44.64- $\mu \text{m}$ pixel with 19.48% fill-factor features a 210.2-ps resolution, 50-ns (8-bit) range TDC with 1.28-LSB differential and 1.92-LSB integral nonlinearity (DNL/INL). The sensor achieves an observation rate of up to 1 MHz through a current-based mechanism that avoids reading empty frames when the photon rates are low. A row-skipping mechanism detects the absence of SPAD activity in a row to increase the duty cycle. These two features require only three transistors in each pixel. The sensor functionality is demonstrated in a quantum imaging experiment that achieves super-resolution.

中文翻译：

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用于量子光学的 32x 32 像素 CMOS 成像器，具有 Per-SPAD TDC，44.64-μm 间距中的 19.48% 填充因子达到 1-MHz 观察率

本文报告了一个 32 $\times $ 用于量子成像应用的 32 单光子雪崩二极管 (SPAD) 时间分辨图像传感器，采用 150 纳米 CMOS 标准技术制造。per-SPAD 时间数字转换器 (TDC) 记录纠缠光子通量的空间互相关函数。每个 44.64- $\mu \text{m}$ 具有 19.48% 填充因子的像素具有 210.2-ps 分辨率、50-ns（8 位）范围 TDC，具有 1.28-LSB 差分和 1.92-LSB 积分非线性 (DNL/INL)。该传感器通过基于电流的机制实现了高达 1 MHz 的观察速率，该机制可避免在光子速率较低时读取空帧。行跳过机制检测一行中没有 SPAD 活动以增加占空比。这两个特征在每个像素中只需要三个晶体管。传感器功能在实现超分辨率的量子成像实验中得到证明。