为了有效地探测海水中微生物的分布情况，搭建了水中微生物的数字全息探测系统，具有原位、无干扰、动态、三维探测等特点。该系统的记录光路基于同轴全息术，并在此基础上引入显微镜头放大系统。实验中采用科学级CCD记录数字全息图，分析了数字再现算法,通过计算机编程计算,得到不同景深处微生物的再现像，再现结果可达到毫米量级以下的精度。实验证明，数字全息技术用于水中微生物的图像化立体探测是高效可行的。

The aim of this paper is to develop a digital holographic imaging (DHI) system, capable of capturing three-dimensional (3D) images of aquatic species, with the characteristics of in situ, non-interference, dynamic and 3D detection. The DHI system records the in-line holographic image with a scientific grade CCD, while a camera lens is used to magnify the holographic image. This optical field is retrieved by numerical algorithms, which enable the reconstruction of the field at different distances relative to the detector from a single hologram. Conclusion is drawn that digital holographic sensing and imaging is an appropriate and highly effective method for aquatic microorganism study.