A ruggedized acousto-optic waveguide comprising a pair of inner plastic plates, a sheet of optical glass sandwiched flush between the inner plates with side edges exposed to ambient light, a transducer acoustically coupled with one end of the sheet of glass, a resilient pad overlaying one of the inner plates, a pair of cover plates mounted about and in compressive engagement with the pair of inner plates and resilient pad, and a set of compression springs coupled with the other end of the sheet of glass applying in-plane compression thereto.