Diffractive spatial optical modulators (SOM) employing a fine-pitch pixel array were introduced. The micromechanical designs of the lead zirconate titanate (PZT) actuator and mirror ribbon structure were optimized for a small volume while maintaining the same level of performance. The same design rule and fabrication equipment were used for a new -pitch and conventional -pitch SOM. The optical efficiency of the new SOM was 78% (zeroth-order diffraction), which is an improvement over that of the -pitch SOM (73%). The full on/off contrast ratio showed no differences, and a high displacement of was achieved. The stress of the Pt/PZT/Pt actuating layer was the main parameter affecting the initial gap height and displacement of the ribbon. The required ribbon flatness could be achieved by applying a stress gradient on the SiN layer. The temperature-sensitive characteristics, which degrade image quality, could be minimized by a mechanical compensation method that takes advantage of the thermal expansion effect of Si substrates. The estimated lifetime of the device is . The developed fine-pitch SOM device has sufficient response time and ribbon displacement to be suitable for high-quality embedded laser-projection displays. The VGA optical module was successfully demonstrated in a mobile laser projection display.