海洋浮游生物原位探测系统对海洋生态研究具有重要意义。研究了一种适合长期在水下观察浮游生物的原位探测系统。系统基于同轴数字全息光路设计, 加入显微放大模块, 使用中心波长525nm的LED光源, 有效降低了激光散斑噪声的同时, 使显微成像的景深达到厘米量级。通过测试得到CCD位置与系统景深的变化关系直方图, 选择合适的光阑直径和CCD位置对标准分辨率板usaf1951和水槽中的浮游生物进行了全息记录和再现;对系统分辨率进行评估, 充分论证LED同轴数字全息显微在海洋浮游生物原位探测中的可行性。

The marine plankton in-situ detection system had great significance to the marine ecological research. An in-situ detection system which is suitable for long-term underwater observation of plankton was researched. The system bases on the coaxial digital holographic optical path design and joins the microscopic amplifier module, used the center wavelengths of 525nm LED light source. As well as it reduces the laser speckle noise effectively to make the depth of field of microscopic imaging to centimetre magnitude at the same time. Obtaining the CCD position and depth of field of histogram changed relationship by testing, and choosing the appropriate aperture diameter and the CCD position to holographic recorded and reappeared of standard resolution of the board usaf1951 and the flum of plankton. The system resolution was evaluated to fully demonstrate the feasibility of LED coaxial digital holographic microscopy in the in-situ detection of marine plankton.