A tilting mirror design for maskless lithography is proposed. In this mirror, the tilting portion occupies about 60% of the entire element area. The surrounding space is made 100% reflective and out-of-phase with respect to the tilting portion. The ratio between the tilting portion of the mirror and the out-of-phase portion is optimized in order to result in equal positive and negative maximum amplitudes over a complete range of tilt angles.