Abstract：Lens-free microscopic technology utilizes Gaborbased inline holographic optical path to capture the interference images generated by illuminating lights through the microsamples, with the help of an area array detector but without any imaging lenses. It is a digital microscopic imaging technology which uses a digitalpictureprocessing method to reconstruct image for the sake of acquiring information from these microsamples. The shrinkage of equivalent pixel elements achieved by pixel superresolution gives more highfrequency information and, further, it promotes the resolution of reconstruction directly. Meanwhile, multiple phase recovery arithmetic tools make the same contributions to resolution indirectly by eliminating the twinimages, especially to the dense samples. Moreover, such technology breaks the limitation in spatial bandwidth product, comparing to the classical optics microscopes, which leads to the highresolution imaging in a larger field of view (FOV). Therefore, it can provide powerful supports for rapidly diagnosing samples with a big field of view in clinical application and examination in the case of resource shortage. Additionally, the booming algorithm with optimizing hardwares renders impetus in datasampling and computing effects, expanding the applications on specimens moving in high speed and on a nanometer scale. The developing tendency of lensfree technology and its matched hard devices are to become compacted both arithmetically and volumetrically. Ultimately, the realtime, three dimensional, colorfullyimaging, portable and separated devices with highresolution can be manufactured.
