摘要 |
A vibration sensor (12) comprises a small flat mirror (72) bonded to a thin metal sheet or beam (68) at the beam's centroid. The beam is clamped at its opposite edges by screws (70) to form a fixed beam with the flat mirror at its midspan, to permit the mirror to move in the direction of its normal, along an axis (54). The beam-mirror assembly, as bolted to a block (34) is placed upon an optical table (12) for measurement of vibrations, thereon. Securement of block (34) between one of its surfaces (38, 44) and with and without a deflecting mirror (66) permits axis (54) to be placed in any one of three orthogonal directions, in order to obtain the orthogonal components of any vibrations exerted upon optical table (12). The components of the vibration in terms of amplitude and frequency are obtained by use of a laser (14), detector (16), a piezoelectric transducer (18), a beam splitter (20), all secured to table (10) and their associated electronic equipment, including a frequency analyzer (80), which constitute a modified Michelson interferometer.
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