2010 Volume 45 Issue 1 Pages 55-59
The measurements of vibration of high-voltage electron microscopes (HVEM) installed on some institutes and universities, including the HVEM of Nagoya University, were carried out to examine the environmental vibration characteristics of the ground and foundation as well as the transmission properties of vibration through the support structure. In particular, the performance for the vibration reduction was investigated on two different types of vibration isolation systems, that is, the suspended mount type (HITACHI) and the double foundation type (JEOL).
As a result, it was clarified that the HVEM of Nagoya University is located on the place of high ground vibration level due to a traffic condition in comparison with the other sites. And it was also confirmed that the countermeasures to the vibration amplification of the support structure and the rocking vibration mode caused by the vibration isolation system are necessary further to realize the higher operability of HVEM.