Abstract The development of infrared (IR) plastic optics for infrared thermal imaging, particularly, in the long‐wave IR (LWIR) spectrum (7–14 µm) is an area of growing technological interest due to the potential advantages associated with plastic optics (e.g., moldability and low cost). The development of a new class of optical polymers, chalcogenide‐based inorganic/organic hybrid polymers (CHIPs) derived from the inverse vulcanization of elemental sulfur, has enabled significant improvements in IR transparency due to reduction of IR absorbing organic comonomer units. The vast majority of effort has focused on new chalcogenide hybrid polymer synthesis and optical property improvements (e.g., refractive index, Abbe number, and LWIR transmission); however, fabrication and IR imaging methodology to prepare optical components has not been demonstrated, which remains critical to develop viable IR plastic optics. A new methodology is reported to fabricate optical components and evaluate LWIR imaging performance of this emerging class of optical polymers. New diffractive flat optics with a Fresnel lens design for these materials have been developed, along with a basic LWIR imaging system to evaluate CHIPs for LWIR imaging. This system‐based approach enables correspondence of copolymer structure‐property correlations with LWIR imaging performance, along with demonstration of room temperature LWIR imaging.
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Solution‐Processed Disordered Plasmonic Surfaces as Optics for Infrared Imaging
In recent years, thermal imaging and sensing technologies have seen dramatic increases in usage for a range of applications. However, the material cost and manufacturing complexity of infrared optics remain a major barrier toward their democratization. Here, a solution‐processed plasmonic reflective filter (PRF) is presented as a scalable, disordered, and low‐cost thermal infrared (TIR) optic. The PRF selectively absorbs sunlight and specularly reflects TIR wavelengths, with a performance comparable to state‐of‐the‐art infrared optics made of materials like Germanium. Unlike the latter, however, the PRF is fabricated using low‐cost materials and a “dip‐and‐dry” chemical synthesis technique, which enables orders of magnitude lower manufacturing costs. The PRF's optical functionality and integration into infrared imaging systems are experimentally demonstrated. The chemical synthesis technique also affords exceptional spectral tuneability and material compatibility compared to traditional fabrication methods. The PRF's tuneable and broadband TIR yield can be augmented by inexpensive dielectric or polymeric filters to yield novel capabilities such as wide‐area ambient temperature surveys. Practically, the PRF represents a significant advance toward democratizing the benefits of thermal imaging and sensing. Scientifically, it represents a previously unexplored optical functionality of disordered materials, and a new direction for versatile chemical synthesis in designing optical components.
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- Award ID(s):
- 2146577
- PAR ID:
- 10574679
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Laser & Photonics Reviews
- Volume:
- 18
- Issue:
- 9
- ISSN:
- 1863-8880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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