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ETN018233-D03
PFM450E Piezo Focus Mount and Controller
As the resonance frequency of actuators varies with load in addition to the minor
variations from product to product, the notch filter is tuneable so that its characteristics
can be adjusted to match those of the actuator. In addition to its centre frequency, the
bandwidth of the notch (or the equivalent quality factor, often referred to as the Q-
factor) can also be adjusted. In simple terms, the Q factor is the center frequency/
