[OPTICAL REVIEW Vol. 1, No. 2 (1994) 278-280]

Generalized Phase-Shifting Algorithm for Dynamic Phase Measurement in Electron-Wave Interferometry

Guanming LAI1, Qingxin RU2, Kazuhiro AOYAMA2 and Akira TONOMURA2

1Present address : Dept. of Electr. and Electron. Eng., Shizuoka University, 3-5-1, Johoku, Hamamatsu, 432 Japan, 2Electron Wavefront Project, Research Development Corporation of Japan, c/o Faculty of Engineering, Toyo University, Nakanodai 2100, Kawagoe, Saitama, 350 Japan

(Accepted August 29, 1994)

A generalized phase-shifting algorithm is implemented in the electron-wave interferometry with a transmission electron microscope, based on simultaneous measurement of the initial phases of the interferograms. The initial phase of each interferogram that has inherent linear carrier fringes is calculated using the Fourier co-efficients of the interferogram itself corresponding to the carrier-frequency. Taking advantage of this phase-shifting method in both spatial resolution and precision, the phase distribution of a biological weak phase object is successfully measured. This promises to be one of the most spectacular application fields for this new technology.

Key words : electron wave interference, electron holography, generalized phase-shifting, flagella filaments