针对全场光学相干层析术实用化时成像速度不高的问题,提出一种基于FPGA控制的相位调制快速全场光学相干层析系统成像方法.首先用FPGA搭建电路以产生频率可调的高准确度正弦信号与脉冲信号,然后利用所产生的信号作为调制频率,采用四步移相法获取光学断层图像.采用该方法对洋葱表皮细胞进行光学断层成像,并与传统相移法及采用单片机调制方式获取的图像进行对比,结果表明该方法不仅能提高成像质量,且对高分辨率光学断层图像的采集时间从目前的4s(0.25 Hz)减少到0.03~0.05s(20Hz~35Hz),提高了系统的成像速度.
In order to improve the imaging speed of full-field optical coherence tomography for practical applications,aphase modulation method for rapid full-field optical coherence tomography was proposed.The Field-Programmable GateArray(FPGA)was used to build the circuits to generate accurate sinusoidal and pulse signals with adjustable frequency.The generated signals were then employed as modulation signals in four step phase shift method to obtain optical sectional images.Finally,the optical tomography images of onion cells were obtained and compared with the ones generated by traditional phase shift method and the single chip-based method.The results show that the method proposed not only can improve the image quality,but also can increase the imaging speed,the time required for reconstructing an optical tomographic image is reduced from 4s(0.25Hz)to 0.03~0.05s(20Hz~35Hz).