An Acousto-Optic Tunable Filter (AOTF) is a pass-band transmission filter, which exploits the acousto-optic interaction inside an anisotropic medium. Anisotropy is a characteristic of a material that implies different properties in different directions. AOTFs are generally fabricated in Tellurium Dioxide, operating within the visible to near/mid infra-red. These filters are used to rapidly and dynamically select a specific wavelength from a broadband or multi-line laser source. As the applied radio frequency is varied, the transmitted wavelength changes, thus “tuning” the wavelength of the beam or image in tens of microseconds or less.