A new micro programmable blazed grating (μPBG) and its application to multispectral imaging

A new micro programmable blazed grating (μPBG) was designed, fabricated and characterized using the two-layer polysilicon surface micromachining process. The μPBG presented is simple in structure and has the capability of continuous spectral tuning for a wide wavelength range. To maximize the operational blazed angle, dimple structure was adopted as the key component for grating slats, and its height was close to the air gap. By the measurements, the developed μPBG sample can reach a maximum blazed angle of ~5. 19° at a driving voltage of 112 V. Accordingly, the blazed wavelength can reach a mid-infrared wavelength of 4. 88 μm. Then, a preliminary experiment to investigate the feasibility of multispectral imaging by using the developed μPBG as the core dispersing element was performed, and the results are encouraging. The advantages of the proposed method for multi-spectral imaging are discussed, and some suggestions for further research are also put forward.