Apparatus and method for estimating bio- information
An apparatus and method for estimating bio-information are provided. The apparatus for estimating bio-information includes: a spectrometer configured to measure a spectrum from an object according to measurement conditions; and a processor configured to obtain signal-to-noise ratio (SNR) values for each wavelength of the spectrum measured by the spectrometer, generate a plurality of simulated absorbance spectra based on the SNR values for each wavelength of the spectrum, and determine an optimal wavelength combination for use in measuring the bio-information based on the plurality of simulated absorbance spectra.
1 . An apparatus for estimating bio-information, the apparatus comprising:
a spectrometer configured to measure a spectrum from an object according to measurement conditions; and
a processor configured to:
obtain signal-to-noise ratio (SNR) values for each wavelength of the spectrum measured by the spectrometer,
generate a plurality of simulated absorbance spectra based on the SNR values for each wavelength of the spectrum,
obtain a plurality of prediction values based on the plurality of simulated absorbance spectra,
calculate a Limit of Detection (LoD) value for each of a plurality of predetermined wavelength combinations, based on at least one of a mean value or a standard deviation of the plurality of prediction values,
determine a wavelength combination from among the plurality of predetermined wavelength combinations having a minimum LoD value from among LoD values of the plurality of predetermined wavelength combinations,
measure, using the spectrometer, spectrums of each wavelength of the determined wavelength combination within a predetermined measurement time for measuring the object,
extract feature values for each wavelength of the determined wavelength combination,
estimate, using a predefined estimation model, the bio-information based on the extracted feature values, and
display, to a user of a device comprising the apparatus, the bio-information and an indication of whether the bio-information is outside of a predetermined range.
2 . The apparatus of claim 1 , wherein the spectrometer comprises:
a light source configured to radiate light onto the object; and
a detector configured to detect an optical signal by receiving light scattered or reflected from the object.
3 . The apparatus of claim 1 , wherein the measurement conditions comprise at least one of an optical path length, a light source intensity for each wavelength of the spectrum, and detector noise characteristics for each wavelength of the spectrum.
4 . The apparatus of claim 1 , wherein the processor is further configured to:
obtain noise equivalent absorbance for each wavelength of the spectrum based on the SNR values for each wavelength of the spectrum, and
generate the plurality of simulated absorbance spectra based on the noise equivalent absorbance for each wavelength of the spectrum.
5 . The apparatus of claim 1 , wherein the processor is further configured to obtain, based on the plurality of simulated absorbance spectra, prediction values of a target component for each of the plurality of predetermined wavelength combinations.
6 . The apparatus of claim 5 , wherein the processor is further configured to obtain the prediction values of the target component for each of the plurality of predetermined wavelength combinations by using at least one of linear regression analysis and component analysis by classical least squares (CLS).
7 . The apparatus of claim 1 , wherein the processor is further configured to:
obtain, based on the LoD values for each of the plurality of predetermined wavelength combinations, a statistical value of the LoD values for each of the plurality of predetermined wavelength combinations, and
determine the wavelength combination in ascending order of the LoD values for each of the plurality of predetermined wavelength combinations.
8 . The apparatus of claim 1 , wherein the wavelength combination is included in at least one of a combination band region and an overtone band region.
9 . The apparatus of claim 1 , wherein the bio-information comprises at least one of an antioxidant level, a blood glucose level, a blood pressure, a lactate level, an alcohol level, a cholesterol level, or a triglyceride level.
10 . The apparatus of claim 1 , wherein the processor is further configured to determine the plurality of predetermined wavelength combinations based on a position of the object and the bio-information to be estimated, and
wherein the plurality of predetermined wavelength combinations comprise wavelengths in at least one of a combination band region, an overtone band region, or an overlap region comprising at least one wavelength in the combination band region and at least one wavelength in the overtone band region.
11 . The apparatus of claim 10 , wherein the wavelength combination comprises at least one wavelength in at least one of the combination band region, the overtone band region, or the overlap region.
12 . The apparatus of claim 10 , wherein wavelengths of the combination band region range from 2040 nanometers (nm) to 2380 nm, and
wherein wavelengths of the overtone band region range from 1540 nm to 1820 nm.
13 . A method of estimating bio-information, the method comprising:
measuring a spectrum from an object according to measurement conditions;
obtaining signal-to-noise ratio (SNR) values for each wavelength of the spectrum;
generating a plurality of simulated absorbance spectra based on the SNR values for each wavelength of the spectrum;
obtaining a plurality of prediction values based on the plurality of simulated absorbance spectra,
calculate a Limit of Detection (LoD) value for each of a plurality of predetermined wavelength combinations, based on at least one of a mean value or a standard deviation of the plurality of prediction values,
determining a wavelength combination from among the plurality of predetermined wavelength combinations having a minimum LoD value from among LoD values of the plurality of predetermined wavelength combinations;
measuring spectrums of each wavelength of the determined wavelength combination within a predetermined measurement time for measuring the object;
extracting feature values for each wavelength of the determined wavelength combination;
estimating, using a predefined estimation model, the bio-information based on the extracted feature values; and
displaying, to a user of a device, the bio-information and an indication of whether the bio-information is outside of a predetermined range.
14 . The method of claim 13 , wherein the measurement conditions comprise at least one of an optical path length, a light source intensity for each wavelength of the spectrum, and detector noise characteristics for each wavelength of the spectrum.
15 . The method of claim 13 , wherein the generating of the plurality of simulated absorbance spectra comprises:
obtaining noise equivalent absorbance for each wavelength of the spectrum based on the SNR values for each wavelength of the spectrum; and
generating the plurality of simulated absorbance spectra based on the noise equivalent absorbance for each wavelength of the spectrum.
16 . The method of claim 13 , wherein the determining of the wavelength combination comprises obtaining prediction values of a target component for each of the plurality of predetermined wavelength combinations, based on the plurality of simulated absorbance spectra.
17 . The method of claim 13 , wherein the determining of the wavelength combination comprises:
obtaining a statistical value of the LoD values for each of the plurality of predetermined wavelength combinations, based on the LoD values for each of the plurality of predetermined wavelength combinations; and
determining the wavelength combination in ascending order of the LoD values for each of the plurality of predetermined wavelength combinations.
18 . The method of claim 13 , wherein the wavelength combination is included in at least one of a combination band region and an overtone band region.