The principle of operation is based on five piezoceramic activators. This provides active isolation and combines with a passive rubber mount that is 100 times stiffer than a pneumatic isolator. Floor amplitudes are usually less than 0.001 inch so the piezo stack range is more than adequate.
Velocity is measured by geophones generating the error signals that control the activators.
The frequency range is divided into bands separated by crossover points. Different isolation mechanisms will therefore respond to different frequencies of vibration. Newport Corp. Irvine, CA 92714. Optical disk mastering K. Taira, T. Nakano, I. Hoshino, T. Taguchi, T. Murakami, N. Takasu, and M. Adachi of Toshiba Corp. have designed, developed, and fabricated a high-density mastering machine. It features UV optics and a high-precision positioning mechanism.