Most of the samples for electron microscopy behave as a phase object, which changes the phase but not amplitude distribution. However, we can measure only the intensity (amplitude) of the complex wave. The phase problem can be determined from Through-focus HR-TEM images, Differential Phase Contrast in STEM, and Electron Holography.

• IWFR (Iterative Wave-Function Reconstruction)
  The IWFR reconstructs a complex wave-function using Gerchberg-Saxton-type iterative algorithm that works with as few as five HR-TEM images.
  
  
• FTSR (Focus and Tilt Series Reconstruction)
  The FTSR reconstructs a complex wave-function using the Wiener filter that requires usually twenty HR-TEM images.
  
  
• QPt (Quantitative Phase Technique)
  The QPt derives a phase distribution only from three bright-field images based on the Transport of Intensity Equation (TIE). The QPt will work at medium-resolution down to atomic resolution.
  
  
• qDPC (Quantitative Differential Phase Contrast)
  The qDPC gives a phase distribution by integrating STEM-DPC (Differential Phase Contrast) signals.
  
  
• HoloDark (Dark-field Holography)
  The HoloDark generates strain maps based on the GPA technique using the phase distribution obtained from dark-field electron hologram.
  
  
• HoloLive (Real-time Holography)
  The HoloLive reconstructs the phase distribution from electron holograms in live (real-time).