Optimizing a micro electro mechanical system (MEMS) based phase-only light modulator (PLM) for improved system performance

The Phase-Only Spatial Light Modulator (PLM) is a piston-mode design of the Digital Micromirror Device (DMD) that Texas Instruments DLP® Products has been developing in recent years. While the manufacturing of the PLM shares many of the same process steps of the traditional DMD, the optical system integration of the two devices are fundamentally different. As a result, new optimization is needed to maximize the performance of the PLM based on the device characteristics. This paper covers the optimization of key pixel parameters – array fill factor, mirror flatness, mirror tilt – and generally how the parameters affect a device performance metric we call Zeroth-Order Efficiency. The various improvements are modeled to ascertain expected performance gains and at what point the performance benefits achieve asymptotic behavior. Theoretical and empirical results are shown for the improved key pixel parameters and their corresponding gains made to Zeroth-Order Efficiency.