An improved window frame and window piece for a micromirror assembly is disclosed herein. The window frame includes a stress-relieving contour positioned in the middle of the frame that can absorb the mechanical stresses applied to the window frame from the ceramic base and from the window piece. The window frame may be comprised of a single piece of sheet metal that has been stamped to include a stress-relieving contour. The stress-relieving contour may be comprised of a variety of shapes, including a “U” shape, an inverted “U” shape, a curved step shape, or other combinations thereof.