The special dispersion and temperature characteristics of diffractive optical element (DOE) make them widely used in optical systems that require both athermalization and achromatic aberrations designs. The multi-layer DOE (MLDOE) can improve the diffraction efficiency of the overall broad waveband, but its diffraction efficiency decreases with changes in ambient temperature. When the ambient temperature changes, the micro-structure heights of MLDOE and the refractive index of the substrate materials change, ultimately affecting its diffraction efficiency, and, further, the optical transform function (OTF). In this paper, the influence of ambient temperature on the diffraction efficiency of MLDOE in a dual-infrared waveband is proposed and discussed, the diffraction efficiency of MLDOE caused by ambient temperature is derived, and a computational imaging method that combines optical design and image restoration is proposed. Finally, a dual-infrared waveband infrared optical system with athermalization and achromatic aberrations corrected based on computational imaging method is designed. Results show that this method can effectively reduce the diffraction efficiency of MLDOE by ambient temperature and improve the imaging quality of hybrid optical systems.
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http://dx.doi.org/10.3390/s22145291 | DOI Listing |
Nano Lett
January 2025
Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan.
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View Article and Find Full Text PDFRSC Adv
January 2025
Centre for Nano Bio Polymer Science and Technology, Department of Physics, St. Thomas College Palai Kerala 686574 India +919446126926.
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June 2025
Department of Biology, Faculty of Mathematics and Natural Sciences, Mulawarman University, Samarinda, 75242, Indonesia.
The use of eggshells as a primary source for developing value-added materials has garnered significant attention in recent years due to their effectiveness as an excellent adsorbent and support. In this study, the Solid-State Dispersion (SSD) method was utilized to prepare composite photocatalysts of eggshells (ES)/TiO₂ in various ratios. TiO₂ and eggshell photocatalysts were also employed as control samples.
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