Projection display technique utilizing three-color-mixing waveguides and microscanning devices

An integrated-optical three-color-mixing projection display system is demonstrated. This projection display system comprises an optical lens, two microscanners, and a 3×1 planar waveguide device using a new combination of SU-8 and JSR photoresists, which are suitable materials for rapid prototyping of integrated optical circuits. The three-color-mixer fabricated by using a low-cost process has been successfully used for color image generation. This study also demonstrates a surface-micromachined optical scanner using two stress-induced polysilicon plates to raise a horizontal mirror. The electrostatically driven mirror could be used for scanning projection display applications. Experimental data show that the optical scanner has a mirror scanning angle up to 18/spl deg/ using a low operating voltage of 25 V, a submillisecond switching time (<600 μs) and optical insertion loss of 0.85 dB is achieved for multimode waveguides. The development of the proposed project display technology could be promising for integrated optics.