Patent · US Expired

Scanning transmission electron microscopes

US4514629A · kind A · utility

18Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 1983
Grant dateApr 30, 1985
Priority date
Expiry dateJun 29, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2237/2805
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a scanning transmission electron microscope 1 the image of the diffraction pattern formed on a phosphor screen 6 as a result of electron beam impingement on a point on the specimen 4 is converted by a camera 7 into a video signal and digitized in an ADC convertor 9 and stored in a digital store 10. The stored signal is then modified by a weighting factor representing a notional pattern overlaying screen 6. The weighting factor may have one of two binary values, representing a notional opaque and transparent pattern, or may have a multiplicity of different values. The modified signals are then added together to provide a picture value for the point of impingement. By this means a complete picture is built up point-by-point. To speed up the picture taking operation diffraction images from different points may be displayed on different parts of screen 6 so that several images can be scanned together by camera 7.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.