Lens-free microscopic technology utilizes Gaborbased inline holographic optical path to capture the interference images generated by illuminating lights through the microsamples, with the help of an area array detector but without any imaging lenses. It is a digital microscopic imaging technology which uses a digitalpictureprocessing method to reconstruct image for the sake of acquiring information from these microsamples. The shrinkage of equivalent pixel elements achieved by pixel superresolution gives more highfrequency 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 twinimages, 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 highresolution 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 datasampling and computing effects, expanding the applications on specimens moving in high speed and on a nanometer scale. The developing tendency of lensfree technology and its matched hard devices are to become compacted both arithmetically and volumetrically. Ultimately, the realtime, three dimensional, colorfullyimaging, portable and separated devices with highresolution can be manufactured.