An Experimental Study on the Penetration of 850nm and 940nm Infrared Radiation into Porcine Tissues Lee Jin-Min1, Kim Kye-Ha2,* 1Ex-Assistant Professor, Dept. of Computer and Electron Communication, Yanbian University of Science and Technology, China 2Professor, Dept. of Nursing Chosun University, Korea *Corresponding author: Kyeha Kim, E-mail: kyehakim@naver.com
Online published on 4 June, 2019. Abstract There have been a number of clinical studies on the effects of far-infrared (FIR) radiation on the human body. It is known that FIR radiation is absorbed in the epidermis of the human body, whereas near-infrared (NIR) radiation penetrates more deeply. However, no experiments have been carried out to determine how deeply NIR penetrates into tissues. This study investigated the penetration depth of NIR radiation into porcine tissue samples using light-emitting diodes (LEDs) with wavelengths of 850 and 940 nm to radiate the tissue samples. The IR signals were modulated at 38 kHz to enable lock-in detection at various sampling depths. The results showed that 940 nm radiation, which travels farther in air, penetrated 50 mm into the tissue samples, whereas the 850-nm radiation penetrated up to 65 mm. The shorter penetration distance of the 940 nm radiation was attributed to the wavelength dependence of water absorption, due to the high water content of the tissue samples. Various medical devices using NIR may effective for human. Top Keywords Infrared rays, light-emitting diode, penetration depth, temperature, wavelength. Top |