Apparatus and method for measuring concentration of hemoglobin using photothermal effect

Patent metadata

Field	Value
Publication number	US-9594026-B2
Application number	US-201514604691-A
Country	US
Kind code	B2
Filing date	Jan 24, 2015
Priority date	Mar 13, 2014
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

The present invention relates to an apparatus for measuring concentration of hemoglobin in blood using a photothermal effect, the apparatus including: a reference light source unit for radiating a reference beam; a photothermal light source unit for radiating a photothermal beam from which the photothermal effect is generated; a cuvette unit for accommodating a collected blood sample thereinto and having first and second reflection layers; and a concentration operation unit for calculating the concentration of hemoglobin by using the phase changes of interference signals generated from the incidence of the reference beam radiated from the reference light source unit onto the first and second reflection layers of the cuvette unit as the photothermal beam radiated from the photothermal light source unit is incident onto the cuvette unit and absorbed by hemoglobin to generate the photothermal effect through the emission of heat.

First claim

What is claimed is:

1. An apparatus for measuring concentration of hemoglobin in blood using a photothermal effect, the apparatus comprising:
a reference light source radiating a reference beam;
a photothermal light source radiating a photothermal beam from which the photothermal effect is generated;
a cuvette accommodating a collected blood sample thereinto and having first and second reflection layers; and
a concentration operator loaded on and executed by a hardware processor and calculating the concentration of hemoglobin by using the phase changes of interference signals generated from the incidence of the reference beam radiated from the reference light source onto the first and second reflection layers of the cuvette unit as the photothermal beam radiated from the photothermal light source is incident onto the cuvette and absorbed by hemoglobin to generate the photothermal effect through the emission of heat,
wherein the concentration operator reads the reflected interference signals through a spectrometer, reads absolute values of complex numbers obtained through inverse Fourier transform of the interference signals, finds the path-length having the greatest absolute value, and obtains the phase in the signal of the path-length.

2. The apparatus according to claim 1 , wherein the reference beam has a given wavelength in which no photothermal effect is generated from hemoglobin.

3. The apparatus according to claim 1 , wherein the photothermal beam has a given wavelength in which the photothermal effect is generated from hemoglobin.

4. The apparatus according to claim 3 , wherein the photothermal beam has the given wavelength in the range of 250 to 600 nm.

5. The apparatus according to claim 1 , wherein the reference light source comprises a reference beam generator adapted to radiate broadband light therefrom, and the reference beam generator includes any one selected in SLED (superluminescent light-emitting diode), LED (light-emitting diode), supercontinuum laser, wavelength-swept (tunable) laser, fiber laser, DFB (distributed feedback) laser, VCSEL (vertical cavity surface emitting) laser and DPSS (diode pumped solid state) laser.

6. The apparatus according to claim 5 , wherein the reference light source further comprises a light signal transmitter adapted to transmit the light signal radiated from the reference beam generator to the cuvette and to transmit the interference signals reflected and returned from the cuvette to the concentration operator.

7. The apparatus according to claim 6 , wherein the light signal transmitter comprises any one selected in a fiber optic coupler, fiber optic splitter, free space interferometer and beam splitter.

8. The apparatus according to claim 1 , wherein the first reflection layer is formed of a transparent material to which light is transmitted, and the blood sample is located between the first reflection layer and the second reflection layer.

9. The apparatus according to claim 1 , wherein the photothermal light source comprises any one selected in a DPSS (diode pumped solid state) laser, LED (light-emitting diode), laser diode, dye laser, gas laser, argon laser and krypton laser.

10. The apparatus according to claim 9 , further comprising a modulation generator located in front of the photothermal light source to provide modulation to the photothermal beam radiated from the photothermal light source.

11. The apparatus according to claim 10 , wherein the modulation generator comprises any one selected in an embedded electronic modulator, optical shutter, optical chopper, AOM (acousto-optic modulator) and EOM (electro-optic modulator).

12. The apparatus according to claim 10 , wherein the concentration operator reads the reflected interference signals through a spectrometer, reads absolute values of complex numbers obtained through inverse Fourier transform of the interference signals, finds the path-length having the greatest absolute value, and obtains the phase in the signal of the path-length, while calculating the hemoglobin concentration with a peak value in a modulation frequency through Fourier transform of the phase change information of the interference signals modulated by the modulation generator.

13. The apparatus according to claim 11 , wherein the concentration operator reads the reflected interference signals through a spectrometer, reads absolute values of complex numbers obtained through inverse Fourier transform of the interference signals, finds the path-length having the greatest absolute value, and obtains the phase in the signal of the path-length, while calculating the hemoglobin concentration with a peak value in a modulation frequency through Fourier transform of the phase change information of the interference signals modulated by the modulation generator.

14. A method for measuring concentration of hemoglobin using a hemoglobin concentration measuring apparatus, the apparatus comprising a reference light source radiating a reference beam, a photothermal light source radiating a photothermal beam from which the photothermal effect is generated, a cuvette accommodating a collected blood sample thereinto and having first and second reflection layers, and a concentration operator for calculating the concentration of hemoglobin by using the phase changes of interference signals generated from the incidence of the reference beam radiated from the reference light source onto the first and second reflection layers of the cuvette as the photothermal beam radiated from the photothermal light source is incident onto the cuvette and absorbed by hemoglobin to generate the photothermal effect through the emission of heat, the method comprising the steps of:
providing the blood sample to the cuvette;
allowing the reference light source to radiate the reference beam;
allowing the reference beam radiated from the reference light source unit to be incident onto the cuvette and reflected onto the first and second reflection layers of the cuvette and detecting the phases of the interference signals generated from the reflection of the reference beam;
allowing the photothermal light source to radiate the photothermal beam; allowing the photothermal beam radiated from the photothermal light source to be incident onto the cuvette and to be absorbed by hemoglobin to generate the photothermal effect through the emission of heat;
allowing the reference beam radiated from the reference light source to be incident onto the cuvette and reflected onto the first and second reflection layers of the cuvette and detecting the phases changes of the interference signals generated from the reflection of the reference beam; and
operating the hemoglobin concentration in accordance with the relationship between the phase changes of the interference signals and the hemoglobin concentration,
wherein the concentration operator reads the reflected interference signals through a spectrometer, reads absolute values of complex numbers obtained through inverse Fourier transform of the interference signals, finds the path-length having the greatest absolute value, and obtains the phase in the signal of the path-length.

Assignees

• Industry-Academic Cooperation Foundation Yonsei Univ

Inventors

• Joo Chulmin
• Yim Jinyeong
• Kim Hun
• Ryu Su Ho

Classifications

• G01N21/171

  with calorimetric detection, e.g. with thermal lens detection · CPC title

• G01N21/45

  using interferometric methods; using Schlieren methods · CPC title

• G01N21/85 Primary

  Investigating moving fluids or granular solids · CPC title