Open AccessMultiband absorbers for the long-wave infrared regime
Author(s) -
Victoria A. Carey,
Mark S. Mirotznik
Publication year - 2017
Publication title -
applied optics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.56.008403
Subject(s) - optics , pixel , absorption (acoustics) , infrared , wavelength , dither , materials science , fourier transform , intensity (physics) , optical filter , physics , telecommunications , computer science , bandwidth (computing) , quantum mechanics
We present the development of a long-wave infrared regime multiband absorption filter with simultaneous wavelength and intensity selectivity. The approach employs a technique we call "spectral dithering" to place single-band absorbing pixels across a unit cell such that their weighted sum describes a multiband absorption spectrum. The number of absorption bands is proportional to the number of unique pixels present. Pixel patterning controls wavelength selectivity, whereas pixel distribution controls intensity selectivity. Using the rigorous coupled-wave method for modelling, a filter with three absorption bands between 6 and 14 μm is designed using the spectral dithering technique. The device is fabricated and experimentally verified using Fourier-transform infrared spectroscopy.