A lightguide assembly including structures to provide for outcoupling of light from an internal reflection structure. In an embodiment, a lightguide assembly includes light transmissive bodies forming respective corrugations which are coupled to one another. Optical coatings are variously disposed between the respective corrugations, wherein the optical coatings provide for redirection of light from the lightguide assembly. In another embodiment, optical coatings are each applied to a respective one of alternate facets of a corrugation. Polymer film portions provide mechanical support for the optical coatings during application to the corrugation.