Circuit design for retina-like image sensor based on space-variant lens array

摘要：

　　Retina-like image sensor is based on the non-uniformity of the human eyes and the log-polar coordinate theory.It has advantages of high-quality data compression and redundant information elimination.However,retina-like image sensors based on the CMOS craft have drawbacks such as high cost,low sensitivity and signal outputting efficiency and updating inconvenience.Therefore,this paper proposes a retina-like image sensor based on space-variant lens array,focusing on the circuit design to provide circuit support to the whole system.The circuit includes the following parts:(1)A photo-detector array with a lens array to convert optical signals to electrical signals;(2)a strobe circuit for time-gating of the pixels and parallel paths for high-speed transmission of the data;(3)a high-precision digital potentiometer for the I-V conversion,ratio normalization and sensitivity adjustment,a programmable gain amplifier for automatic generation control(AGC),and a A/D converter for the A/D conversion in every path;(4)the digital data is displayed on LCD and stored temporarily in DDR2 SDRAM;(5)a USB port to transfer the data to PC;(6)the whole system is controlled by FPGA.This circuit has advantages as lower cost,larger pixels,updating convenience and higher signal outputting efficiency.Experiments have proved that the grayscale output of every pixel basically matches the target and a non-uniform image of the target is ideally achieved in real time.The circuit can provide adequate technical support to retina-like image sensors based on space-variant lens array.

关键词： Photoelectric conversion Non-uniform imaging Circuit design Image sensors Bionic vision FPGA Log-polar coordinate

作者: Hongxun Gao Qun Hao Xuefeng Jin Jie Cao Yue Liu Yong Song Fan Fan

作者单位: School of Optoelectronics,Beijing Institute of Technology,Beijing,100081,China

会议类型: 国际会议

会议名称: 2013 International Conference on Optical Instrument and Technology (OIT’2013)(2013年光学仪器与技术国际会议)

会议地点: 北京

会议语种:英文

页码: 1-8

在线出版日期: 2013-11-17（万方平台首次上网日期，不代表论文的发表时间）