A Digital Offset Reduction Method for Dynamic Comparators Based on Phase Measurement

Author(s):  
Andres Amaya ◽  
Javier Ardila ◽  
Elkim Roa
Author(s):  
Akira Tonomura

Electron holography is a two-step imaging method. However, the ultimate performance of holographic imaging is mainly determined by the brightness of the electron beam used in the hologram-formation process. In our 350kV holography electron microscope (see Fig. 1), the decrease in the inherently high brightness of field-emitted electrons is minimized by superposing a magnetic lens in the gun, for a resulting value of 2 × 109 A/cm2 sr. This high brightness has lead to the following distinguished features. The minimum spacing (d) of carrier fringes is d = 0.09 Å, thus allowing a reconstructed image with a resolution, at least in principle, as high as 3d=0.3 Å. The precision in phase measurement can be as high as 2π/100, since the position of fringes can be known precisely from a high-contrast hologram formed under highly collimated illumination. Dynamic observation becomes possible because the current density is high.


2019 ◽  
Vol 7 (1) ◽  
pp. 256-259
Author(s):  
P.Balasowandari ◽  
Dr. V.Anusuya

2020 ◽  
Vol 140 (3) ◽  
pp. 175-183
Author(s):  
Kengo Kawauchi ◽  
Hayato Higa ◽  
Hiroki Watanabe ◽  
Keisuke Kusaka ◽  
Jun-ichi Itoh

2015 ◽  
Vol 135 (4) ◽  
pp. 241-250 ◽  
Author(s):  
Hideo Koseki ◽  
Masaki Nagata ◽  
Hideo Hosogoe ◽  
Hiroshi Takada ◽  
Takanori Shuto ◽  
...  

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