Yasutomi Keita, Usui Takahiro, Han Sang-Man, Takasawa Taishi, Kagawa Keiichiro, Kawahito Shoji
Opt Express. 2014 Aug 11;22(16):18904-13. doi: 10.1364/OE.22.018904.
This paper presents an indirect time-of-flight (TOF) measurement technique with an impulse photocurrent response of a lock-in pixel. By using a short-pulse laser, the generated photocurrent can be presumed to be an impulse response. This facilitates the utilization of the full high-speed performance of the photodetector and gives high range resolution. As a proof-of-concept, a test chip with a lock-in pixel based on draining-only modulation was implemented using 0.11 μm CMOS image-sensor technology. The test chip achieved a range resolution of 0.29 mm in a 50-mm measurable range, which corresponds to a time resolution of 1.9 ps and the successful acquisition of a 3-mm example step.
本文提出了一种基于锁相像素脉冲光电流响应的间接飞行时间（TOF）测量技术。通过使用短脉冲激光，所产生的光电流可被假定为脉冲响应。这有利于充分利用光电探测器的高速性能，并提供高距离分辨率。作为概念验证，采用0.11μm CMOS图像传感器技术实现了基于仅耗尽调制的锁相像素测试芯片。该测试芯片在50mm可测量范围内实现了0.29mm的距离分辨率，这对应于1.9ps的时间分辨率，并成功采集了一个3mm的示例台阶。
