Figure 7
Schematic diagram of self-excited microcantilever (a). Schematic diagram of the self-excited system (b) includes a workpiece, a microcantilever, a piezo actuator, a self-excited electronic circuit and an optical lever that consists of a laser and a photodiode. Self-excited electronic circuit (c) includes a voltage follower, a phase shifter, an integrating circuit and three inverting amplifiers.
