|
100000 Pa, 15 keV, 160 pA |
4000 Pa, 10 keV, 230 pA |
|
21100 Pa, 10 keV, 230 pA |
Gaseous detector used |
It has been shown both theoretically and experimentally that specimens can be examined at any pressure up to one atmosphere without loss of resolution. Uncoated wool fibers are shown imaged either with a scintillating BSE detector or a low bias GDD at 4000 Pa (GDD), 21100 Pa (GDD) and 100000 Pa (= 1 atmosphere) pressure (BSE). These original images still remain unique waiting to be reproduced by a commercial instrument. Considering the "old fashioned" technical resources available on the prototype, these results clearly show the possibilities still lying ahead. They also constitute another benchmark as far as pressure level and imaging capabilities that an ESEM is possible to have
(2), (6), (13), (17), (34). There is no technical reason to prevent this capability from any fully fledged ESEM, and there are no additional manufacturing costs and no other complications exist in preventing all users to attain any pressure they wish. No lower performance is to be expected from any properly designed commercial ESEM. It is only a matter of supplying a set of appropriate fittings with the basic instrument having the correct design.A further extension of the ASEM, as a logical conclusion of this field, is the Atmospheric Scanning Transmission Electron Microscope (ASTEM) as proposed in a latest patent application.
Below are images for the cases mentioned above:
|
100000 Pa, 15 keV, 160 pA |
4000 Pa, 10 keV, 230 pA |
|
21100 Pa, 10 keV, 230 pA |
Gaseous detector used |
