{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T01:13:53Z","timestamp":1778634833174,"version":"3.51.4"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,4,2]],"date-time":"2023-04-02T00:00:00Z","timestamp":1680393600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100015641","name":"Tateisi Science and Technology Foundation","doi-asserted-by":"publisher","award":["2201015"],"award-info":[{"award-number":["2201015"]}],"id":[{"id":"10.13039\/100015641","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015641","name":"Tateisi Science and Technology Foundation","doi-asserted-by":"publisher","award":["JP18K12070"],"award-info":[{"award-number":["JP18K12070"]}],"id":[{"id":"10.13039\/100015641","id-type":"DOI","asserted-by":"publisher"}]},{"name":"JSPS KAKENHI","award":["2201015"],"award-info":[{"award-number":["2201015"]}]},{"name":"JSPS KAKENHI","award":["JP18K12070"],"award-info":[{"award-number":["JP18K12070"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Routine blood pressure measurement is important for the early detection of various diseases. Recently, cuffless blood pressure estimation methods that do not require cuff pressurization have attracted attention. In this study, we investigated the effect of the light source wavelength on the accuracy of blood pressure estimation using only two physiological indices that can be calculated with photoplethysmography alone, namely, heart rate and modified normalized pulse volume. Using a newly developed photoplethysmography sensor that can simultaneously measure photoplethysmograms at four wavelengths, we evaluated its estimation accuracy for systolic blood pressure, diastolic blood pressure, and mean arterial pressure against a standard cuff sphygmomanometer. Mental stress tasks were used to alter the blood pressure of 14 participants, and multiple linear regression analysis showed the best light sources to be near-infrared for systolic blood pressure and blue for both diastolic blood pressure and mean arterial pressure. The importance of the light source wavelength for the photoplethysmogram in cuffless blood pressure estimation was clarified.<\/jats:p>","DOI":"10.3390\/s23073689","type":"journal-article","created":{"date-parts":[[2023,4,3]],"date-time":"2023-04-03T02:32:27Z","timestamp":1680489147000},"page":"3689","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Investigation of Optimal Light Source Wavelength for Cuffless Blood Pressure Estimation Using a Single Photoplethysmography Sensor"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7081-9447","authenticated-orcid":false,"given":"Sogo","family":"Toda","sequence":"first","affiliation":[{"name":"Ishikawa College, National Institute of Technology, Tsubata 929-0392, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4271-1543","authenticated-orcid":false,"given":"Kenta","family":"Matsumura","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1001\/jama.2013.284427","article-title":"2014 evidence-based guideline for the management of high blood pressure in adults: Report from the panel members appointed to the Eighth Joint National Committee (JNC 8)","volume":"311","author":"James","year":"2014","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1038\/nrcardio.2013.1","article-title":"Assessment and management of blood-pressure variability","volume":"10","author":"Parati","year":"2013","journal-title":"Nat. Rev. Cardiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1124","DOI":"10.1161\/CIRCRESAHA.118.313220","article-title":"Adherence in Hypertension","volume":"124","author":"Burnier","year":"2019","journal-title":"Circ. Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1161\/HYPERTENSIONAHA.111.178657","article-title":"Prognostic value of the variability in home-measured blood pressure and heart rate: The Finn-Home Study","volume":"59","author":"Johansson","year":"2012","journal-title":"Hypertension"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1161\/HYPERTENSIONAHA.109.140798","article-title":"Prognostic value of reading-to-reading blood pressure variability over 24 hours in 8938 subjects from 11 populations","volume":"55","author":"Hansen","year":"2010","journal-title":"Hypertension"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1007\/BF02442797","article-title":"New oscillometric method for indirect measurement of systolic and mean arterial pressure in the human finger. Part 1: Model experiment","volume":"20","author":"Yamakoshi","year":"1982","journal-title":"Med. Biol. Eng. Comput."},{"key":"ref_7","unstructured":"Kaplan, N.M., and Victor, R.G. (2014). Kaplan\u2019s Clinical Hypertension, LWW. [11th ed.]."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1879","DOI":"10.1109\/TBME.2015.2441951","article-title":"Toward Ubiquitous Blood Pressure Monitoring via Pulse Transit Time: Theory and Practice","volume":"62","author":"Mukkamala","year":"2015","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Sharma, M., Barbosa, K., Ho, V., Griggs, D., Ghirmai, T., Krishnan, S.K., Hsiai, T.K., Chiao, J.-C., and Cao, H. (2017). Cuff-less and continuous blood pressure monitoring: A methodological review. Technologies, 5.","DOI":"10.3390\/technologies5020021"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"287","DOI":"10.33549\/physiolres.932581","article-title":"Pulse transit time and blood pressure during cardiopulmonary exercise tests","volume":"63","author":"Wibmer","year":"2014","journal-title":"Physiol. Res."},{"key":"ref_11","first-page":"598","article-title":"Is pulse transit time a good indicator of blood pressure changes during short physical exercise in a young population?","volume":"2010","author":"Muehlsteff","year":"2010","journal-title":"Annu. Int. Conf. IEEE Eng. Med. Biol. Soc."},{"key":"ref_12","first-page":"738","article-title":"Continuous noninvasive blood pressure measurement by pulse transit time","volume":"2006","author":"Fung","year":"2004","journal-title":"Conf. Proc. IEEE Eng. Med. Biol. Soc."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/j.compeleceng.2012.09.005","article-title":"Noninvasive cuffless blood pressure estimation using pulse transit time and Hilbert\u2013Huang transform","volume":"39","author":"Choi","year":"2013","journal-title":"Comput. Electr. Eng."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Kumar, N., Agrawal, A., and Deb, S. (2014, January 24\u201327). Cuffless BP measurement using a correlation study of pulse transient time and heart rate. Proceedings of the 2014 International Conference on Advances in Computing, Communications and Informatics (ICACCI), Delhi, India.","DOI":"10.1109\/ICACCI.2014.6968642"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1152\/japplphysiol.00657.2005","article-title":"Pulse transit time measured from the ECG: An unreliable marker of beat-to-beat blood pressure","volume":"100","author":"Payne","year":"2006","journal-title":"J. Appl. Physiol. (1985)"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"217","DOI":"10.3109\/08037051.2015.1030901","article-title":"Continuous blood pressure measurement using the pulse transit time: Comparison to intra-arterial measurement","volume":"24","author":"Patzak","year":"2015","journal-title":"Blood Press"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1007\/s00421-011-1983-3","article-title":"Continuous blood pressure measurement by using the pulse transit time: Comparison to a cuff-based method","volume":"112","author":"Gesche","year":"2012","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1109\/RBME.2021.3109643","article-title":"Noninvasive Continuous Blood Pressure Estimation From Pulse Transit Time: A Review of the Calibration Models","volume":"15","author":"Barvik","year":"2022","journal-title":"IEEE Rev. Biomed Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5117","DOI":"10.1109\/IEMBS.2006.259612","article-title":"Continuous blood pressure monitoring using ECG and finger photoplethysmogram","volume":"2006","author":"Chua","year":"2006","journal-title":"Conf. Proc. IEEE Eng. Med. Biol. Soc."},{"key":"ref_20","unstructured":"Samria, R., Jain, R., Jha, A., Saini, S., and Chowdhury, S.R. (2014). 2014 IEEE Region 10 Symposium, IEEE."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Li, Z., and He, W. (2021). A Continuous Blood Pressure Estimation Method Using Photoplethysmography by GRNN-Based Model. Sensor, 21.","DOI":"10.3390\/s21217207"},{"key":"ref_22","unstructured":"Maher, N., Elsheikh, G., Anis, W.R., and Emara, T. (2019). International Conference on Advanced Machine Learning Technologies and Applications, Springer."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"eaap8674","DOI":"10.1126\/scitranslmed.aap8674","article-title":"Smartphone-based blood pressure monitoring via the oscillometric finger-pressing method","volume":"10","author":"Chandrasekhar","year":"2018","journal-title":"Sci. Transl. Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"e11479","DOI":"10.7717\/peerj.11479","article-title":"Cuffless blood pressure estimation based on haemodynamic principles: Progress towards mobile healthcare","volume":"9","author":"Yamakoshi","year":"2021","journal-title":"PeerJ"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"7298","DOI":"10.1038\/s41598-018-25681-5","article-title":"Cuffless blood pressure estimation using only a smartphone","volume":"8","author":"Matsumura","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1111\/j.1469-8986.1981.tb01545.x","article-title":"Pulse transit time as an indicator of arterial blood pressure","volume":"18","author":"Geddes","year":"1981","journal-title":"Psychophysiology"},{"key":"ref_27","unstructured":"Guyton, A.C., and Hall, J.E. (1986). Human Physiology and Mechanisms of Disease, Saunders. [6th ed.]."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1111\/1469-8986.3910064","article-title":"A new model of individual differences in hemodynamic profile and blood pressure reactivity","volume":"39","author":"Gregg","year":"2002","journal-title":"Psychophysiology"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"656","DOI":"10.1111\/j.1469-8986.1990.tb03189.x","article-title":"Hemodynamics of blood pressure responses during active and passive coping","volume":"27","author":"Sherwood","year":"1990","journal-title":"Psychophysiology"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1088\/0967-3334\/34\/3\/359","article-title":"Validation of normalized pulse volume in the outer ear as a simple measure of sympathetic activity using warm and cold pressor tests: Towards applications in ambulatory monitoring","volume":"34","author":"Lee","year":"2013","journal-title":"Physiol. Meas."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1027\/0269-8803\/a000197","article-title":"Inter-method reliability of pulse volume related measures derived using finger-photoplethysmography: Across sensor positions and light intensities","volume":"32","author":"Matsumura","year":"2018","journal-title":"J. Psychophysiol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0167-8760(00)00162-8","article-title":"Normalized pulse volume (NPV) derived photo-plethysmographically as a more valid measure of the finger vascular tone","volume":"41","author":"Sawada","year":"2001","journal-title":"Int. J. Psychophysiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1111\/1523-1747.ep12479191","article-title":"The optics of human skin","volume":"77","author":"Anderson","year":"1981","journal-title":"J. Investig. Derm."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1117\/1.429919","article-title":"Optical Properties of Circulating Human Blood in the Wavelength Range 400\u20132500 nm","volume":"4","author":"Roggan","year":"1999","journal-title":"J. Biomed. Opt."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2543","DOI":"10.1088\/0022-3727\/38\/15\/004","article-title":"Optical properties of human skin, subcutaneous and mucous tissues in the wavelength range from 400 to 2000 nm","volume":"38","author":"Bashkatov","year":"2005","journal-title":"J. Phys. D Appl. Phys."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"R1","DOI":"10.1088\/0967-3334\/28\/3\/R01","article-title":"Photoplethysmography and its application in clinical physiological measurement","volume":"28","author":"Allen","year":"2007","journal-title":"Physiol. Meas."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1016\/0169-2607(89)90159-4","article-title":"Skin photoplethysmography\u2014A review","volume":"28","author":"Kamal","year":"1989","journal-title":"Comput. Methods Programs Biomed."},{"key":"ref_38","first-page":"e484","article-title":"2017 ACC\/AHA\/AAPA\/ABC\/ACPM\/AGS\/APhA\/ASH\/ASPC\/NMA\/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology\/American Heart Association Task Force on Clinical Practice Guidelines","volume":"138","author":"Whelton","year":"2018","journal-title":"Circulation"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1161\/HYPERTENSIONAHA.107.089797","article-title":"Diastolic blood pressure and mortality in the elderly with cardiovascular disease","volume":"50","author":"Protogerou","year":"2007","journal-title":"Hypertension"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1111\/j.1469-8986.1981.tb03021.x","article-title":"Young Psychophysiologist Award address, 1980. Cardiovascular responses to effortful active coping: Implications for the role of stress in hypertension development","volume":"18","author":"Light","year":"1981","journal-title":"Psychophysiology"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1111\/j.1469-8986.1978.tb01344.x","article-title":"The relationship among heart rate, caratid dP\/dt, and blood pressure in humans as a function of the type of stress","volume":"15","author":"Obrist","year":"1978","journal-title":"Psychophysiology"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"80233","DOI":"10.1109\/ACCESS.2020.2990438","article-title":"RGB and near-infrared light reflectance\/transmittance photoplethysmography for measuring heart rate during motion","volume":"8","author":"Matsumura","year":"2020","journal-title":"IEEE Access"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/7\/3689\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:08:37Z","timestamp":1760123317000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/7\/3689"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,4,2]]},"references-count":42,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2023,4]]}},"alternative-id":["s23073689"],"URL":"https:\/\/doi.org\/10.3390\/s23073689","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,4,2]]}}}