小型CMOS相机系统设计及其硬件实现

Design and hardware implementation of the small-size CMOS camera system

采用MT9V032型CMOS数字图像传感器设计了一款完整的小型化、低功耗相机.基于初级像差理论,设计了焦距为12.95mm、F数为5的光学系统.该系统体积小、结构紧凑,在空间频率83线对每毫米处,各视场调制传递函数均优于0.5;电子学系统以现场可编程门阵列作为时序控制平台,控制CMOS输出数字视频信号,数字视频信号通过差分芯片以低压差分信号格式输出到图像采集卡,最后在计算机上成像.实验结果表明,这种相机像质良好、功耗低、移植性强、可靠性高.当时钟为26.6MHz时,帧频为60帧/秒,并可通过调节内部寄存器的值实现多种模式,特别适用于对相机体积以及成像质量要求较高的场合.

A camera with a small-size and low-power is designed, using a CMOS MT9V032 as the digital image sensor. Based on the primary aberration theory, the optical system with the small size and compact structure is designed whose focal length is 12.95 mm and whose F number is 5, and the modulation transfer functions （MTF） of all fields are better than 0.5 at the spatial frequency of 83 lp/mm; we use FPGA as the timing control platform for the electronic system and the digital video signal of the CMOS output which is delivered through the differential chip in the low voltage differential signal （LVDS） output format to the image acquisition card. Finally, we can see the image on the computer. Experimental results show that the designed CMOS camera has a good image quality, low power, portability, and high reliability, and that the frame rate is 60 frames/s when the clock is 26.6 MHz, and it could achieve a variety of modes by adjusting the values of the internal registers, which is particularly suitable for the high requirements occasion in the camera volume and high imaging quality.