Detection method of Two-Dimensional Distribution of the Phase State of Water using Near-Infrared Light-Absorption

2016 Fiscal Year Final Research Report

• Project/Area Number: 26420405
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Measurement engineering
• Research Institution: Nagano National College of Technology
• Principal Investigator: NAKASHIMA Toshiro 長野工業高等専門学校, 電子制御工学科, 教授 (50416690)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: optical sensing / light-absorption / near-infrared light / water / liquid phase / solid phase

Outline of Final Research Achievements

We have developed a detection method of two-dimensional distribution of the phase state of water using near-infrared light-absorption. In this case, we focused on the light-absorption characteristics of water. It is known that the absorption peak shifts to longer wavelength when the liquid phase (water state) changes into the solid phase (ice state). We have proposed a new evaluation index based on absorbed light intensity ratio at two wavelengths. The experimental results showed that the proposed evaluation index can be used as a criterion to detect the liquid phase or the solid phase. To get the two-dimensional distribution of the index, we have proposed a detection method with new image capturing optics. It has been confirmed that this method is effective for two-dimensional monitoring the water freezing process with supercooling by the experiment.

Free Research Field

光応用計測