| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently exert an effect of an active mass damper (AMD3) attached to equipment D which is an object while preventing the equipment from becoming large and heavy in vain. SOLUTION: The equipment D such as TEM is placed on a surface plate 1 of an air spring type vibration eliminating table A, and the AMD3 is attached in the upper part of the mirror tower d2 thereof. The vibration eliminating table A and the equipment D are expressed by a first mass portion m0 supported to a foundation by a first spring element k0, and a second mass portion m1 supported to the first mass portion m0 via a second spring element k1, and a vibration model with three degrees of freedom with the AMD3 attached to the second mass portion m1 as an additional vibration system is structured. A spindle 9 is attached to the surface plate 1 of the vibration eliminating table A in such a manner that a mass ratio m0/m1 of the first mass portion m0 to the second mass portion m1 in the vibration model becomes 1.5-3.0. COPYRIGHT: (C)2011,JPO&INPIT |
