Cao Yuan, Pan Xiaofang, Zhao Xiaojin, Wu Huisi
College of Electronic Science and Technology, Shenzhen University, Shenzhen 518060, China.
Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Sensors (Basel). 2014 Dec 15;14(12):24132-45. doi: 10.3390/s141224132.
In this paper, a novel analog gamma correction scheme with a logarithmic image sensor dedicated to minimize the quantization noise of the high dynamic applications is presented. The proposed implementation exploits a non-linear voltage-controlled-oscillator (VCO) based analog-to-digital converter (ADC) to perform the gamma correction during the analog-to-digital conversion. As a result, the quantization noise does not increase while the same high dynamic range of logarithmic image sensor is preserved. Moreover, by combining the gamma correction with the analog-to-digital conversion, the silicon area and overall power consumption can be greatly reduced. The proposed gamma correction scheme is validated by the reported simulation results and the experimental results measured for our designed test structure, which is fabricated with 0.35 μm standard complementary-metal-oxide-semiconductor (CMOS) process.
本文提出了一种新颖的模拟伽马校正方案，该方案采用对数图像传感器，旨在最小化高动态应用中的量化噪声。所提出的实现方法利用基于非线性压控振荡器（VCO）的模数转换器（ADC）在模数转换期间执行伽马校正。结果，在保持对数图像传感器相同高动态范围的同时，量化噪声不会增加。此外，通过将伽马校正与模数转换相结合，可以大大减小硅面积和总体功耗。所提出的伽马校正方案通过报告的仿真结果以及针对我们设计的测试结构测量的实验结果得到验证，该测试结构采用0.35μm标准互补金属氧化物半导体（CMOS）工艺制造。
