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Chalcogenide hybrid inorganic/organic polymers (CHIPs) are a new class of optical polymeric materials for imaging and photonic applications due to their high refractive indices and high optical transmission at visible and infrared wavelengths. In this study, we characterize these polymers to study the refractive index and delve into the electronic properties by way of measurements of their dielectric constants. Ellipsometry is used to determine the refractive indices for wavelengths from 500 nm to 12 µm, while we use capacitance measurements on thin film capacitors with a range of areas to find the dielectric constant. The results are in line with expectations based on the sulfur composition of the polymers-indices range from 1.7 to 1.85, and dielectric constants range from 2.6 to 3. With these measurements, these sulfur polymer materials are established to be good candidates for optical and photonic applications, particularly with respect to telecommunications. The dielectric constants suggest that applications such as electro-optic devices and capacitors may also be viable.
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Fabrication of Plastic Optics from Chalcogenide Hybrid Inorganic/Organic Polymers for Infrared Thermal Imaging
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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- PAR ID:
- 10518678
- Publisher / Repository:
- WIley
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 12
- Issue:
- 7
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/adom.202301971
