Methods of improving resolution on a heterodyne acousto-optic vibrometer

In this article, two approaches for improving the resolution of an acousto-optic vibrometer were developed and investigated. Both methods were able to double the resolution of first order optical system. In the first method, the resolution of the system was improved using a second order diffraction beam instead of first order in the measurement layout. The second method applied multiple first order beams, which are the positive and negative first order beams. In addition, an optical system was designed to measure the wavelength of the acoustic wave using the first and second order to verify the improvement in measurement resolution.