  Ptychography, a high-resolution phase imaging technique using precise
in-plane translation information, has been widely applied in modern synchrotron
radiation sources across the globe. A key requirement for successful
ptychographic reconstruction is the precise knowledge of the scanning
positions, which are typically obtained by a physical interferometric
positioning system. Whereas high-throughput positioning poses a challenge in
engineering, especially in nano or even smaller scale. In this work, we propose
a novel scanning imaging framework that does not require any prior position
information from the positioning system. Specifically, our scheme utilizes the
wavefront modulation mechanism to reconstruct the object functions at each scan
position and the shared illumination function, simultaneously. The scanning
trajectory information is extracted by our subpixel image registration
algorithm from the overlap region of reconstructed object functions. Then, a
completed object function can be obtained by assembling each part of the
reconstructed sample functions. High-quality imaging of biological sample and
position recovery with sub-pixel accuracy are demonstrated in proof-of-concept
experiment. Based on current results, we find it may have great potential
applications in high-resolution and high throughput phase imaging.
