数字全息显微为生物医学、微纳加工和粒子场检测等领域提供了一种快速、非接触、三维光学检测手段。但在实际应用中，由于激光散斑噪声的存在和数值孔径的限制，使得全息显微的成像质量下降，分辨率受限。针对这些问题，本项目提出了一种基于LED照明的数字全息显微方法。使用红蓝两色LED作为照明光源和彩色CCD记录，从记录的单幅双色全息图中分离出两幅单波长同轴全息图，利用相移和双波长之间形成的合成波长，实现无包裹的全场实时观测。利用不同波长的层析厚度不同，消除层析观测中的背景噪声，提高纵向分辨率。为了提高横向分辨率，使用LED阵列作为照明光源。通过同时记录LED阵列中不同位置灯珠照明的全息图，利用频谱滤波和合成孔径实现高分辨率再现像。通过本项目研究，可以为实用化的高性能数字全息显微镜的开发和应用打下基础。

Digital holographic microscopy (DHM) provides a real-time, non-contact, three-dimensional optical observation and measurement method for the biomedical research, micro-machining, particle field research and so on. However, the speckle noise and the limited numerical aperture reduce the quality of imaging and the spatial resolution. In order to solve these problems, a scheme based on LED illumination digital holographic microscopy is proposed in this project. By using red and blue LEDs as the illumination sources and CCD camera as a recording device, two single wavelength in-line holograms can be extracted from the single-shot dual-wavelength hologram. With the aid of phase-shifting and the synthetic wavelength between the two wavelengths, a real-time full field imaging can be achieved without phase unwrapping. At the same time, the background noise in the tomography can be eliminated since the imaging depths of the two wavelengths are different, and the axial resolution can be improved. In order to improve the lateral resolution of DHM, a LED array is used as the light source. A hologram with multi-angle illumination from difference positions of LED beads is recorded. Then, the spectrum filtering and synthetic aperture are performed to realize the high resolution imaging. These works of the project will contribute to further development and application of high performance digital holographic microscope.