Electron microscope
AssigneeHitachi, Ltd.
InventorsKazuo Shii, Toshiyuki Ohashi
Life of this patent
Estimating the term…
Abstract
An electron microscope is disclosed in which an electron beam impinges upon a specimen at a predetermined angle of incidence, the incident azimuth of the electron beam incident upon the specimen is continuously changed, and the electron beam having passed through the specimen is made large in angular spread by a magnifying lens system and then projected onto a viewing screen to form a visual enlarged image of the specimen on the viewing screen; and in which the astigmatism of the magnifying lens system is shown on the viewing screen as the blur of the image.
Claims24
An electron microscope comprising means for generating an electron beam;
- means for causing the electron beam to impinge upon a specimen at a predetermined incident angle while continuously changing the incident azimuth of the electron beam incident upon the specimen at said predetermined incident angle at a predetermined frequency to transmit the electron beam through the specimen;
- a magnifying lens system for magnifying the transmitted electron beam in angular spread;
- and a viewing fluorescent screen for receiving the magnified electron beam projected thereon to form a visual enlarged image of the specimen on the viewing fluorescent screen wherein the beam is continuously rotated so that the resulting image on the viewing screen will be blurred in the direction of astigmatism.
An electron microscope comprising means for generating an electron beam along a predetermined axis;
- first deflection means for deflecting said electron beam away from said axis at a first predetermined angle;
- second deflecting means for deflecting said thus-deflected electron beam back to a location on said axis;
- holder means for holding a specimen at said location at which said beam is returned to said axis by said second deflecting means so that said electron beam is transmitted through said specimen at a predetermined incident angle;
- control means for controlling said first and second deflection means in a coordinate manner to effect continuous rotation of the deflection azimuth of the electron beam as it impinges on said specimen;
- a magnifying lens system for magnifying the transmitted electron beam in angular spread;
- and a viewing fluorescent screen for receiving the magnified electron beam projected thereon to produce a visual enlarged image of the specimen, wherein the beam is continuously rotated so that the resulting image on the viewing screen will be blurred in the direction of astigmatism.
In an electron microscope of the direct viewing type in which an electron beam is transmitted through a specimen, magnified in angular spread and projected onto a viewing screen, the improvement comprising means for deflecting said electron beam so that it impinges at a selected location on said specimen with a predetermined angle less than 90.degree. and means for continuously rotating the incident azimuth of the electron beam at said location at a predetermined frequency so that the resulting image on the viewing screen will be blurred in the direction of astigmatism.
Dependencies are inferred from the claim text.