基于锁相光子计数技术,提出一种多波长并行检测的单像素空间频率域成像(SFDI)系统。以一个数字微镜器(DMD)为待测多波长漫反射光的调制光源,以另一个DMD为漫反射光采集、编码与会聚设备,使得会聚后的漫反射光通过锁相光子计数技术实现不同波长的解调分离,同时降低了系统成本。引入压缩感知图像恢复理论,有效缩短了多次空间编码引起的单像素成像时间。实验结果表明,所提SFDI系统只需要进行像素总数20%左右的编码,即可准确重构多波长下仿体表面漫反射光图像。

Based on the lock-in photon-counting technique, a multi-wavelength single pixel spatial frequency domain imaging (SFDI) parallel detection system is proposed. With a digital micro-mirror device (DMD) as the modulated light source of diffuse reflected light to be measured under different wavelengths and another DMD as the equipment for the acquisition, coding, and convergence of diffuse reflection light, the converged diffuse reflected light is demodulated separately under different wavelengths based on the lock-in photon-counting technique, and simultaneously the cost of the proposed system is reduced. The time consumption of single-pixel imaging caused by multiple spatial encoding is effectively compensated via the introduction of the compressed sensing theory. The experimental results show that the proposed SFDI system can realize the reconstruction of diffuse reflection light from phantom surfaces under multiple wavelengths by encoding with only 20% of total pixels.