Piezoelectric transducer (PZT) is often used in the field of precision measurement to realize the micro-positioning function, such as Fizeau interferometer. But due to its inherent severe hysteresis and nonlinear characteristics, the use of piezoelectric transducer is affected. A piezoelectric transducer control instrument was designed to measure the displacement characteristic curve of piezoelectric transducer. The instrument included the control system and data received system. The control system produces a triangular wave signal with adjustable amplitude and frequency, then calculated from received signal to drive the piezoelectric transducer. The output displacement information of piezoelectric transducer is collected by the signal acquisition circuit composed of displacement sensor and ADC analog-digital converter. The purpose of the single chip is collecting and processing displacement data. According to the experimental results, we can get the characteristics curve of the piezoelectric transducer, which support the basis analysis and available for the future experiment.
Cylindrical surface is widely used for modern industry. However, cylindrical surface measurement has become a quite difficult problem. In this paper, we will present coherent technique to measure cylindrical surface, including cylindrical surface and cylindrical ring. Inner surfaces measurement of cylindrical ring can be achieved without map stitching, by a Fizeau interferometer with a 90°conical mirror. The alignment of this arrangement, however, is very crucial to the accomplishment. Any small misplacement of 90° cone or hollow cylinder from their ideal settings may result in large measurement errors. These errors are not intuitive and hard to be removed if their origins are not well understood. In other words, it is very important to know how these measurement errors are generated from the optical misalignment in order to eliminate them. Finally, we have aligned our experimental setup and gotten some results which were so closed with our theoretical analysis.