A Gate-Controlled Lateral Thyristor-Based Pixel With Low-Light-Level Extension for High Dynamic Range Applications
A Gate-Controlled Lateral Thyristor-Based Pixel With Low-Light-Level Extension for High Dynamic Range Applications
复制标题
具有低光级扩展功能的栅极控制横向晶闸管像素，适用于高动态范围应用
DOI：
10.1109/jsen.2022.3221808
复制
发表时间：
2022-12-15
影响因子：
4.3
通讯作者：
Wang, Zheyao
中科院分区：
文献类型：
--
作者：
Sun, Keyang;Pan, Liyang;Wang, Zheyao
提出了一种基于门控侧晶闸管（GC-LT）的像素配置，以实现具有高动态范围（HDR）的微光扩展。我们之前的工作已经证明了GC-LT在弱光条件下具有很高的灵敏度，并且触发时间对光功率敏感，范围为<inline-formula> < text -math符号="LaTeX">$1\乘以10^{-{9}}$ </ text -math></inline-formula>至<inline-formula> < text -math符号="LaTeX">$2.5\乘以10^{-{6}}$ </ text -math></inline-formula> W/cm2。在本文中，实现了采样电路和斜率跟踪法来获得光敏触发时间。提出了一种多短周期斜率法来补偿长曝光时间下泄漏电流的影响。通过精心设计操作方案，GC-LT也可以像传统的光电二极管一样移位。此外，基于gc - lt的像素可以在晶闸管、线性和对数模式下工作，以扩展动态范围。仿真验证了新提出的器件和像素电路。结果表明，三种模式组合后，像素的动态范围均高于160 dB，最小可检测信号低至<inline-formula> < text -math notation="LaTeX">$1\乘以10^{-{9}}$ </ text -math></inline-formula> W/cm2。
A pixel configuration based on a gate-controlled lateral thyristor (GC-LT) is proposed to achieve low-light-level extension with a high dynamic range (HDR). Our previous work has demonstrated that the GC-LT has a high sensitivity in low-light-level conditions, and the trigger time is sensitive to the optical power ranging from <inline-formula> <tex-math notation="LaTeX">$1\times 10^{-{9}}$ </tex-math></inline-formula> to <inline-formula> <tex-math notation="LaTeX">$2.5\times 10^{-{6}}$ </tex-math></inline-formula> W/cm2. In this article, a sampling circuit and a slope following method are implemented to obtain the light-sensitive trigger time. A multiple short-period slopes method is proposed to compensate for the leakage current effects in long exposure time. By elaborately designing the operating scheme, the GC-LT can also be shifted as a conventional photodiode. Also, the GC-LT-based pixel can be operated in thyristor, linear, and logarithmic modes to extend the dynamic range. Simulation is performed to validate the newly proposed device and pixel circuit. The results show that by combining the three modes, the dynamic range of the pixel is higher than 160 dB, and the minimum detectable signal is as low as <inline-formula> <tex-math notation="LaTeX">$1\times 10^{-{9}}$ </tex-math></inline-formula> W/cm2.