Development of the broadband Fourier transform IR imaging spectrometer with common path wavefront division phase-shift interferometry for compact satellite payload

Le résumé fourni par la source

We have developed a compact broadband infrared imaging Fourier transform spectrometer, referred to as the 2D FTIR, employing common path wavefront division phase-shift interferometry. The system comprises a 3-reflector point-topoint optical setup with overlapping paths, incorporating two free-form mirrors and a pair of 20 mm high and 40 mm wide planar mirrors. Initially, we establish a one-dimensional multi-slit object plane with spacing tailored to match the FPA detector pixel size, effectively preventing destructive interference. Through precise optimization of the parameters of the two free-form mirrors (Mirror 1: 4th-order Zernike polynomial; Mirror 2: 6th-order Zernike polynomial), we achieve precise beam collimation, reflection through a phase shifter, and subsequent refocusing onto the FPA detector. Utilizing a commercial uncooled bolometer camera with a resolution of 640x480 pixels and a pixel size of 17μm, we attain optimal performance across the 4-20μm wavelength range, coupled with a generous 6mm diameter field of view. The spectrometer boasts a remarkable wavenumber resolution of 2.7 cm-1, with R (λ=4μm) ≈ 1000, alongside a spatial resolution of 34μm. All components seamlessly fit within a 170x150x80 mm vacuum frame. The 2D FT-IR enables the acquisition of spectral maps post-image capture and offers a broad measurement wavelength range of 4-20 μm. After completion of development, we plan to employ it to study the generation mechanisms of cryogenically frozen organic matter simulating Titan's haze and to measure the low-temperature continuous spectral transmittance and refractive index of the GREX-PLUS spectroscopic components. Additionally, due to its high vibration resistance and compact design, we intend to deploy it as a spectrometer for compact satellites developed by JAXA. Lastly, it will serve as a pivotal test instrument for the PLANETS telescope, facilitating the evaluation of the telescope's resistance to atmospheric disturbances.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.