Wrap-free phase retrieval using a series of intensity measurements produced by tuning the illumination wavelength

摘要

In this paper, we present a phase retrieval method where a sequence of diffraction speckle intensities, recorded by tuning the illumination wavelength, is used. These recordings, combined with an iterative calculation method, allow the reconstruction of the amplitude and the phase of the wavefront. The main advantages of this method are: simple optical setup and high immunity to noise and environmental disturbance, since no reference beam or additional moving parts are needed. Furthermore, this method allows for an extended wrap-free phase measurement range by using synthetic wavelengths. The technique shows great potential in some fields of micro-metrology, such as lensless phase contrast imaging and wavefront sensing.