Fabrication and experimental investigation of diffraction characteristics for a pitch-tunable grating based on SOG process

Based on the micro-opto-electro-mechanical systems (MOEMS) technology, a new micro programmable grating with tunable pitch is designed and fabricated by using silicon-on-glass (SOG) processing. The pitch-tunable grating has prominent advantages over the conventional optical devices such as simple operation, continuous adjusting, and wide modulation. The change of the grating pitch results in the change of monochromatic diffraction angle and chromatic wavelength. Then two experimental setups for practically measuring the change of monochromatic diffraction angle and chromatic wavelength are designed and established, respectively. The characteristics of the grating according to the designed structural dimensions agree very well with the experimental results, which proves that the grating has good modulation performances. This work lays a good foundation for the future research in micro spectrometers and optical communication and provides valuable technical references.