title: Coaxial Dual-wavelength Interferometric Method for a Thermal Infrared Focal-plane-array with Integrated Gratings.
abstract: Uncooled infrared (IR) focal-plane-array (FPA) with both large sensing range and high sensitivity is a great challenge due to the limited dynamic range of the detected signals. A coaxial dual-wavelength interferometric system was proposed here to detect thermal-induced displacements of an ultrasensitive FPA based on polyvinyl-chloride(PVC)/gold bimorph cantilevers and carbon nanotube (CNT)-based IR absorbing films. By alternately selecting the two displacement measurements performed by λ1 (=640 nm) and λ2 (=660 nm), the temperature measuring range with greater than 50% maximum sensitivity can be extended by eight-fold in comparison with the traditional single-wavelength mode. Meanwhile, the relative measurement error over the full measuring range is below 0.4%. In addition, it offers a feasible approach for on-line and on-wafer FPA characterization with great convenience and high efficiency.
authors.affiliation: Institute of Instrument Science and Technology, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Yuanfang
authors.initials: Y
authors.lastname: Shang
authors.affiliation: Institute of Instrument Science and Technology, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Xiongying
authors.initials: X
authors.lastname: Ye
authors.affiliation: Institute of Opto-electronic Engineering, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Liangcai
authors.initials: L
authors.lastname: Cao
authors.affiliation: Institute of Instrument Science and Technology, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Song
authors.affiliation: Institute of Instrument Science and Technology, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Jinyang
authors.initials: J
authors.lastname: Feng