基于相位调制的运动目标多光谱关联成像研究

Research on multispectral correlation imaging of moving target based on phase modulation

为克服扫描方式多光谱成像无法捕获动态场景下的多光谱数据,提出了一种基于相位调制实现运动目标单次曝光多光谱成像方法。该方法将关联成像技术、压缩感知技术与光谱成像相结合,在成像光路中引入空间随机相位调制器,对运动目标物体三维图谱信息数据进行调制和压缩,然后利用探测器获取二维混叠信号,实现单次曝光获取运动目标的三维图谱信息重构,具有光能利用率高、成像时间短、系统结构简单等优点。实验结果表明:单帧CCD探测信号的电子数均值从200 e^(-)按100 e^(-)的间隔增加到1 300 e^(-)时,随着电子数均值增加,重构图像相对均方根误差rRMSE值对应减小,重构图像质量提高;当步进电机以30 Hz速度带动目标物体连续运动时,可获得较好质量运动物体的多光谱重构图像;采用光谱仪对目标物体中不同谱段的光谱分布曲线进行测试,所得结果与重构图像的光谱分布曲线相吻合,证明了该方法的有效性。研究结果对多光谱关联成像技术在无人机平台、动态监测等领域的应用提供了有益借鉴。

In order to overcome the inability of scanning multi-spectral imaging to capture multi-spectral data in dynamic scenes,a single^(-)exposure multispectral imaging method for moving targets was proposed based on phase modulation.This method combined associated imaging technology,compressed sensing technology and spectral imaging,introduced a spatial random phase modulator into the imaging light path,modulated and compressed the three^(-)dimensional map information data of the moving target object,then used the two-dimensional aliasing signal obtained by the detector to reconstruct the three^(-)dimensional map information to achieve a single exposure and simultaneously obtained the three^(-)dimensional map information of the moving target.It had the advantages of high utilization rate of light energy,short imaging time,and simple system structure.The experimental results show that when the average electron number of a single frame of CCD detection signal increases from 200 e^(-)at intervals of 100 e^(-)to 1300 e^(-),as the average r RMSE value of the electron number increases,the relative root mean square error of the reconstructed image decreases correspondingly,and the reconstruction improved image quality;when the stepper motor drives the target object to continuously move at a speed of 30 Hz,a multi-spectral reconstructed image of the moving object with better quality can be obtained;a spectrometer is used to test the spectral distribution curves of different spectrum bands in the target object,and the results obtained are basically consistent with the spectral distribution curves of the reconstructed image,which proves the effectiveness of the method.The research results provide a useful reference for the application of multi-spectral correlation imaging technology in UAV platforms,dynamic monitoring and other fields.