As a promising technology, refractive index (RI) sensing has been developed for biosensing and chemosensing applications as well as for multiple industrial applications. Nevertheless, conventional RI sensors are confined by their operating principle or detection devices in terms of high sensitivity or a wide detection range. This study experimentally demonstrates metasurface-based spectrometer-free RI sensing through a spatial weighted variance (SWV)-based analysis of metasurface-generated vortex beams. The proposed liquid-immersed metasurface device creates a focused vortex beam at a single wavelength of 1550 nm, whose focusing effect varies according to the surrounding medium. The images, captured by a position-fixed near-infrared camera, exhibit divergent beam profiles determined by certain RI values. The SWV is used to assess the degree of divergence and is calculated based on the recorded beam images to quantify the variation of the RI. Thus, the proposed RI sensing scheme concurrently achieves high sensitivity (113 598/RIU), wide detection range (1.3164–1.3825), and high resolution (8.8 × 10−6 RIU). The proposed image-based spectrometer-less RI sensing methods overcome the constraints of instruments that are unavoidable in conventional detection techniques. Compared to the existing methods, the proposed strategy is simpler, less costly, more user-friendly, and usable in a broader range of sensing applications.
KSP Keywords
Focusing effect, High Sensitivity, High-resolution, Image-based, Infrared camera, Near-Infrared(NIR), Refractive index sensor, Sensing applications, Sensing scheme, Sensor based, Single wavelength
Copyright Policy
ETRI KSP Copyright Policy
The materials provided on this website are subject to copyrights owned by ETRI and protected by the Copyright Act. Any reproduction, modification, or distribution, in whole or in part, requires the prior explicit approval of ETRI. However, under Article 24.2 of the Copyright Act, the materials may be freely used provided the user complies with the following terms:
The materials to be used must have attached a Korea Open Government License (KOGL) Type 4 symbol, which is similar to CC-BY-NC-ND (Creative Commons Attribution Non-Commercial No Derivatives License). Users are free to use the materials only for non-commercial purposes, provided that original works are properly cited and that no alterations, modifications, or changes to such works is made. This website may contain materials for which ETRI does not hold full copyright or for which ETRI shares copyright in conjunction with other third parties. Without explicit permission, any use of such materials without KOGL indication is strictly prohibited and will constitute an infringement of the copyright of ETRI or of the relevant copyright holders.
J. Kim et. al, "Trends in Lightweight Kernel for Many core Based High-Performance Computing", Electronics and Telecommunications Trends. Vol. 32, No. 4, 2017, KOGL Type 4: Source Indication + Commercial Use Prohibition + Change Prohibition
J. Sim et.al, “the Fourth Industrial Revolution and ICT – IDX Strategy for leading the Fourth Industrial Revolution”, ETRI Insight, 2017, KOGL Type 4: Source Indication + Commercial Use Prohibition + Change Prohibition
If you have any questions or concerns about these terms of use, or if you would like to request permission to use any material on this website, please feel free to contact us
KOGL Type 4:(Source Indication + Commercial Use Prohibition+Change Prohibition)
Contact ETRI, Research Information Service Section
Privacy Policy
ETRI KSP Privacy Policy
ETRI does not collect personal information from external users who access our Knowledge Sharing Platform (KSP). Unathorized automated collection of researcher information from our platform without ETRI's consent is strictly prohibited.
[Researcher Information Disclosure] ETRI publicly shares specific researcher information related to research outcomes, including the researcher's name, department, work email, and work phone number.
※ ETRI does not share employee photographs with external users without the explicit consent of the researcher. If a researcher provides consent, their photograph may be displayed on the KSP.