An optical element device and method of fabrication thereof are described herein. An example optical device may include an optical element (100). The optical element (100) may have an optical path material (105) to allow a light to pass therethrough. The optical path material (105) may have a first end portion (110) with a first end surface (112), a second end portion (110) with a second end surface (112), and a middle portion (115) between the first and second end portions (110) with an interior (116) and an exterior surface (117). A coating (120) may be disposed along the exterior surface (117) and diffused into the optical path material (105). The coating (120) may minimize leakage of the light from the interior (116) through the exterior (117) surface.