US 12,484,808 B2
Method and device for measuring concentration of component
Masahito Nakamura, Tokyo (JP); Yujiro Tanaka, Tokyo (JP); Michiko Seyama, Tokyo (JP); and Daichi Matsunaga, Tokyo (JP)
Assigned to NTT, INC., Tokyo (JP)
Appl. No. 17/416,611
Filed by NTT, Inc., Tokyo (JP)
PCT Filed Dec. 10, 2019, PCT No. PCT/JP2019/048257
§ 371(c)(1), (2) Date Jun. 21, 2021,
PCT Pub. No. WO2020/137517, PCT Pub. Date Jul. 2, 2020.
Claims priority of application No. 2018-240800 (JP), filed on Dec. 25, 2018.
Prior Publication US 2022/0079479 A1, Mar. 17, 2022
Int. Cl. A61B 5/145 (2006.01); A61B 5/00 (2006.01); A61B 5/1455 (2006.01)
CPC A61B 5/14532 (2013.01) [A61B 5/0053 (2013.01); A61B 5/0095 (2013.01); A61B 5/0048 (2013.01); A61B 5/0059 (2013.01); A61B 5/0093 (2013.01); A61B 5/145 (2013.01); A61B 5/1455 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A component concentration measuring method comprising:
a first step of suppressing blood flow in a measurement site of a measurement subject by applying pressure around the measurement site;
a second step of irradiating the measurement site with a light beam having a wavelength that is absorbed by a measurement target substance, and detecting a photoacoustic signal generated at the measurement site when a set time has elapsed after the pressure of the first step has started to be applied around the measurement site;
a third step of obtaining a concentration of the measurement target substance using the photoacoustic signal;
a fourth step of stopping applying pressure around the measurement site after detecting the photoacoustic signal; and
periodically repeating the first step of starting applying the pressure, the second step of detecting the photoacoustic signal, and the fourth step of stopping applying the pressure, wherein a period from a first start of applying the pressure of the first step to a second start of applying the pressure of the first step equals an interval of vasomotion of a blood vessel at the measurement site, wherein the set time in the second step is (T−Δt)/2, and a time during which applying the pressure is stopped in the fourth step is (T+Δt)/2, wherein T is the period from the first start of applying the pressure to the second start of applying the pressure, and Δt is a duration of detecting the photoacoustic signal in the second step wherein the measurement target substance is glucose.