Frequency Range of Operation of the Piezoelectric Transducer of the Acousto-Optic Filter

Abstract

The problem of spectral range anomalous reduction of acousto-optic filters is considered. In this work, acousto-optic tellurium dioxide material characteristics with a cut angle $\alpha$=10o have been studied theoretically and experimentally. The crystal is used in an acousto-optic filter for processing optical images in visible and infrared light. At light wavelengths $\lambda$=1.15 and $\lambda=0.63 \mu m$, the Bragg curves are calculated. Estimates are made of the filter tuning range based on optical wavelengths. The electrical filter tuning range is experimentally determined based on the frequency dependence of the RF power absorbed by the piezoelectric filter transducer. When measuring the diffraction efficiency in the operating mode of the deflector, it is found that the range of filter tuning in terms of optical wavelengths turns out to be different from that predicted as a result of measuring the electrical characteristics of the transducer.