  Ptychography is a promising phase retrieval technique for visible light,
X-ray and electron beams. Conventional ptychography reconstructs the amplitude
and phase of an object light from a set of the diffraction intensity patterns
obtained by the X-Y moving of the probe light. The X-Y moving of the probe
light requires two control parameters and accuracy of the locations. We propose
ptychography by changing the area of the probe light using only one control
parameter, instead of the X-Y moving of the probe light. The proposed method
has faster convergence speed. In addition, we propose scaled ptychography using
scaled diffraction calculation in order to magnify retrieved object lights
clearly.
