Work

Wide-range adaptive piezoelectric MEMS-Fabry-Pérot filter for gas spectral identification

Year: 2026

Type: article

Abstract: Infrared spectroscopy ranks among the most extensively employed analytical techniques for gas spectral identification applications. Conventional infrared spectrometers, however, are often plagued by inherent limitations, including a large physical footprint, high costs, and an inevitable trade-off between spectral resolution and optical throughput. To address these issues, this study proposes a piezoelectric micro-electro-mechanical systems (MEMS) tunable Fabry-Perot filter (FPF) fabricated using a 4-inch wafer-level bonding process. The FPF features a large optical aperture of 3.2 mm and a sweeping rate of 250 Hz. The FPF cavity length is tunable by four pairs of piezoelectric-driven folded beams. Parallelism can be further optimized through applying a DC voltage to each beam individually, thereby achieving a low dynamic deformation and, thus an approximate 10% improvement in transmittance is obtained. This design achieves a free spectral range (FSR) of 101.6 nm, full width at half maximum (FWHM) below 3 nm, and an optimized peak transmission exceeding 90%. Ultimately, through the constructed gas spectral identification system, the MEMS-FPF-based near-infrared spectrometer achieved transmission spectral identification of C 2 H 2 and HCN gases in the tuning frequency range of 100 Hz.

Source: Optics Express

DOI: 10.1364/oe.589456