A UV-transmissable window assembly for a DMD device includes a UV-transmissable glass window provided in a frame. The window and frame are bonded together to preferably effect a hermetic seal therebetween. Optical coatings specific to the intended wavelength of light transmission are applied to the inner and outer surfaces of the glass window to reduce reflection and increase light transmission therethrough. The window assembly, and DMD provided with the same, is adapted for excellent transmission of ultraviolet light, even at the deep ultraviolet portion of the spectrum. The DMD window assembly has application in the medical arts, both surgery and device manufacture, in the production of integrated circuits (IC), and in other optical lithography applications, among other fields.