Design of Multi-Wavelength Optical Sensor Module for Depth-Dependent Photoplethysmography
Department of Biomedical engineering, Chonnam National University, Yeosu 59626, Korea
*
Author to whom correspondence should be addressed.
Sensors 2019, 19(24), 5441; https://doi.org/10.3390/s19245441
Received: 4 November 2019
/
Revised: 2 December 2019
/
Accepted: 6 December 2019
/
Published: 10 December 2019
(This article belongs to the Collection Medical Applications of Sensor Systems and Devices)
The multi-wavelength photoplethysmography sensors were introduced to measure depth-dependent blood volume based on that concept that the longer the light wavelength, the deeper the penetration depth near visible spectrum band. In this study, we propose an omnidirectional optical sensor module that can measure photoplethysmogram while using multiple wavelengths, and describe implementation detail. The developed sensor is manufactured by making a hole in a metal plate and mounting an LED therein, and it has four wavelength LEDs of blue (460 nm), green (530 nm), red (660 nm), and IR (940 nm), being arranged concentrically around a photodetector. Irradiation light intensity was measured by photoluminescent test, and photoplethymogram was measured with each wavelength simultaneously at a periphery of the human body such as fingertip, earlobe, toe, forehead, and wrist, in order to evaluate the developed sensor. As a result, the developed sensor module showed a linear increase of irradiating light intensity according to the number of LEDs increases, and pulsatile waveforms were observed at all four wavelengths in all measuring sites.
View Full-Text
Keywords:
blood volume; light penetration; multiple wavelength; optical sensor; photoplethysmography
▼
Show Figures
Figure 1
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
MDPI and ACS Style
Han, S.; Roh, D.; Park, J.; Shin, H. Design of Multi-Wavelength Optical Sensor Module for Depth-Dependent Photoplethysmography. Sensors 2019, 19, 5441. https://doi.org/10.3390/s19245441
AMA Style
Han S, Roh D, Park J, Shin H. Design of Multi-Wavelength Optical Sensor Module for Depth-Dependent Photoplethysmography. Sensors. 2019; 19(24):5441. https://doi.org/10.3390/s19245441
Chicago/Turabian StyleHan, Sangjin, Donggeun Roh, Junyung Park, and Hangsik Shin. 2019. "Design of Multi-Wavelength Optical Sensor Module for Depth-Dependent Photoplethysmography" Sensors 19, no. 24: 5441. https://doi.org/10.3390/s19245441
Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.
