Device for measuring light absorption materials in blood
First Claim
1. A device for measuring a light absorption material in blood, comprising:
- light emitting means for emitting light, having a plurality of different wavelengths, onto a living tissue;
light receiving means for receiving light outputted from the light emitting means and transmitted through or reflected from the living tissue, the light receiving means outputting a signal corresponding to an intensity of the light transmitted through or reflected from the living tissue;
D.C./A.C. detecting means for obtaining a D.C. component and an A.C. component of a signal corresponding to each wavelength that is output from the light receiving means, respectively;
A.C. to D.C. ratio detecting means for obtaining an A.C. to D.C. ratio signal, which is a ratio of the A.C. component to the D.C. component for each wavelength calculated by the D.C./A.C. detecting means;
component extracting means for extracting a component from the A.C. to D.C. ratio signal having a predetermined frequency value, or a higher frequency value, for each wavelength which is obtained by the A.C. to D.C. ratio detecting means;
extracted component ratio detecting means for obtaining a ratio of extracted component signals for corresponding different wavelengths outputted from the light receiving means, which is extracted by the component extracting means; and
information detecting means for detecting information about a light absorption material in blood, based on the ratio detected by the extracted component ratio detecting means.
1 Assignment
0 Petitions
Accused Products
Abstract
A red light and an infrared light which are emitted from a light emitting portion 2 are transmitted through a fingertip 4 of a subject and are converted into electric signals by a light receiving portion 3. The respective signals are separated and amplified and are then sent to a CPU 8. In the CPU 8, the input signals are divided into D.C. components DC1 and DC2 and A.C. components AC1 and AC2, changes ΔA1=(AC/DC) 1 and ΔA2=(AC/DC)2 in an absorbance are calculated, high frequency components thereof are extracted, a mutual ratio Ψ is calculated, and a noise removing waveform is calculated based thereon. Based on the noise removing waveform, a pulse wave is detected, a pulse rate is calculated, a display wave form is calculated and an oxygen saturation is calculated. These are displayed through a display unit 11.
-
Citations
14 Claims
-
1. A device for measuring a light absorption material in blood, comprising:
-
light emitting means for emitting light, having a plurality of different wavelengths, onto a living tissue;
light receiving means for receiving light outputted from the light emitting means and transmitted through or reflected from the living tissue, the light receiving means outputting a signal corresponding to an intensity of the light transmitted through or reflected from the living tissue;
D.C./A.C. detecting means for obtaining a D.C. component and an A.C. component of a signal corresponding to each wavelength that is output from the light receiving means, respectively;
A.C. to D.C. ratio detecting means for obtaining an A.C. to D.C. ratio signal, which is a ratio of the A.C. component to the D.C. component for each wavelength calculated by the D.C./A.C. detecting means;
component extracting means for extracting a component from the A.C. to D.C. ratio signal having a predetermined frequency value, or a higher frequency value, for each wavelength which is obtained by the A.C. to D.C. ratio detecting means;
extracted component ratio detecting means for obtaining a ratio of extracted component signals for corresponding different wavelengths outputted from the light receiving means, which is extracted by the component extracting means; and
information detecting means for detecting information about a light absorption material in blood, based on the ratio detected by the extracted component ratio detecting means. - View Dependent Claims (2, 3, 4, 5, 6, 7)
pulse rate detecting means for detecting a pulse rate based on the ideal signal.
-
-
4. The device for measuring a light absorption material in blood according to claim 2, further comprising:
display means for displaying a waveform of the ideal signal.
-
5. The device for measuring the light absorption material in blood according to the claim 1, wherein said predetermined frequency value is substantially a pulsation frequency value of living tissue.
-
6. The device for measuring a light absorption material in blood according to claim 1, wherein the information about the light absorption material in blood is an oxygen saturation.
-
7. The device for measuring a light absorption material in blood according to claim 1, wherein two wavelengths are used as the different wavelengths.
-
8. A device for measuring a light absorption material in blood, comprising:
-
light emitting means for emitting light, having a plurality of different wavelengths, onto a living tissue;
light receiving means for receiving light outputted from the light emitting means and transmitted through or reflected from the living tissue, the light receiving means outputting a signal corresponding to an intensity of the light transmitted through or reflected from the living tissue;
D.C./A.C. detecting means for obtaining a D.C. component and an A.C. component of a signal corresponding to each wavelength that is output from the light receiving means;
A.C. to D.C. ratio detecting means for obtaining an A.C. to D.C. ratio signal, which is a ratio of the A.C. component to the D.C. component for each wavelength calculated by the D.C./A.C. detecting means;
noise condition deciding means for deciding at least whether a noise component included in the A.C. to D.C. ratio signal, around a predetermined frequency value or a higher frequency value, is large;
said noise condition detecting means comprising;
signal processing means for processing the A.C. to D.C. ratio signal for each wavelength which is obtained by the A.C. to D.C. ratio detecting means to detect information about a light absorption material in blood, said signal processing means comprising;
component extracting means for extracting a component from the A.C. to D.C. ratio signal having said predetermined frequency value or a higher frequency value for each wavelength which is obtained by the A.C. to D.C. ratio detecting means if the noise component for said predetermined frequency value or a higher frequency value, is large;
extracted component ratio detecting means for obtaining a ratio of extracted component signals for corresponding different wavelengths outputted from the light receiving means, which is extracted by the component extracting means; and
information detecting means for detecting information about a light absorption material in blood, based on the ratio detected by the extracted component ratio detecting means. - View Dependent Claims (9, 10, 11, 12, 13, 14)
pulse rate detecting means for detecting a pulse rate based on the ideal signal.
-
-
11. The device for measuring a light absorption material in blood according to claim 9, further comprising:
display means for displaying a wave form of the ideal signal.
-
12. The device for measuring a light absorption material in blood according to the claim 8, wherein said predetermined frequency value is substantially a pulsation frequency value of living tissue.
-
13. The device for measuring a light absorption material in blood according to claim 8, wherein the information about the light absorption material in blood is an oxygen saturation.
-
14. The device for measuring a light absorption material in blood according to claim 8, wherein two wavelengths are used as the different wavelengths.
Specification