A double gimbal optical image stabilizer driven by piezoelectric stacks

With the advantages of high accuracy and fast response, piezoelectric actuators are used to drive optical image stabilizers. As a piezoelectric stack is not tensile, preload voltage is required for a traditional piezoelectric driven optical image stabilizer, which wastes electricity and adversely affects the stack's performance. In this paper, we propose a double gimbal optical image stabilizer, whereupon a prototype is machined and its performance is assessed. Two piezoelectric stacks are used to produce the forward and reverse actuation, respectively, in which case the preload voltage is not essential. Owing to the isolation of the gimbal, the output coupling of the two piezoelectric actuators is less than 1%. The presented stabilizer has the actuation range of ±50 µm and effectively tracks the sinusoidal signals with the frequency below 46 Hz.