System and method of a biosensor for detection of health parameters

Abstract

A photoplethysmography (PPG) circuit obtains PPG signals at a plurality of wavelengths of light reflected from tissue of a user. A processing device generates parameters using the PPG signals to determine a glucose level in blood flow of the user. The parameters include one or more ratio values obtained using the plurality of PPG signals; a phase delay between the plurality of PPG signals; a correlation of phase shape between the plurality of PPG signals or a periodicity of one or more of the plurality of PPG signals.

1 . A system, comprising:
 an optical circuit configured to obtain a plurality of PPG signals at a plurality of wavelengths reflected from or transmitted through tissue of a user, wherein the plurality of wavelengths have varying penetration depths of tissue;   one or more processing devices configured to:
 determine one or more PPG parameters using the plurality of PPG signals; and 
 determine a health index using the one or more PPG parameters, wherein the health index indicates a vascular health of the user. 
   
     
     
         2 . The system of  claim 1 , wherein the one or more processing devices are configured to determine the one or more PPG parameters by:
 determining at least one of the following PPG parameters: a phase delay between a first PPG signal and a second PPG signal of the plurality of PPG signals, a correlation of phase shape between the first PPG signal and the second PPG signal of the plurality of PPG signals or a periodicity of first PPG signal or the second PPG signal of the plurality of PPG signals.   
     
     
         3 . The system of  claim 1 , wherein the one or more processing devices are further configured to:
 determine an insulin release event using at least a first PPG signal of the plurality of PPG signals, wherein the first PPG signal is obtained from a wavelength of light in a range of 380 nm-410 nm.   
     
     
         4 . The system of  claim 3 , wherein the one or more processing devices are further configured to:
 determine the one or more PPG parameters using at least the first PPG signal, wherein the first PPG signal is obtained during the insulin release event.   
     
     
         5 . The system of  claim 4 , wherein the one or more processing devices are further configured to:
 determine a relative change in diameter of vessels during the insulin release event; and   determine the health index using the relative change in diameter of vessels.   
     
     
         6 . The system of  claim 1 , wherein the one or more processing devices are further configured to determine the one or more PPG parameters by:
 determining a first AC component of a first PPG signal of the plurality of PPG signals, wherein the first PPG signal is obtained using a first wavelength of light in a range of 380 nm-410 nm; and   determining a second AC component of a second PPG signal of the plurality of PPG signals, wherein the second PPG signal is obtained using a second wavelength of light equal to or above 660 nm.   
     
     
         7 . The system of  claim 6 , wherein the one or more processing devices are further configured to determine the one or more PPG parameters by:
 determining a first ratio R value using the first AC component and the second AC component.   
     
     
         8 . The system of  claim 7 , wherein the one or more processing devices are further configured to determine the health index, wherein the health index indicates a diabetic risk in the user. 
     
     
         9 . A device, comprising:
 at least one memory configured to store a plurality of PPG signals obtained using a plurality of wavelengths reflected from or transmitted through tissue of a user, wherein the plurality of wavelengths have varying penetration depths of the tissue of the user; and   one or more processing circuits configured to:
 determine one or more R values using the plurality of PPG signals; 
 determine one or more PPG parameters using the plurality of PPG signals; and 
 determine a health index of the user using the one or more R values and the one or more PPG parameters. 
   
     
     
         10 . The device of  claim 9 , wherein the one or more processing circuits are configured to determine the one or more R values using the plurality of PPG signals by:
 determining a first R value using a first PPG signal and a second PPG signal of the plurality of PPG signals, wherein the first PPG signal is obtained using a first wavelength of light in a range of 380 nm-410 nm and the second PPG signal is obtained using a second wavelength of light at or above 660 nm; and   determining a second R value using the first PPG signal and a third PPG signal of the plurality of PPG signals, wherein the third PPG signal is obtained using a third wavelength of light in a range of 510 nm-550 nm.   
     
     
         11 . The biosensor of  claim 10 , wherein the one or more processing circuits are configured to determine the one or more PPG parameters using the plurality of PPG signals by:
 determining at least one of: a phase delay between the first PPG signal and the second PPG signal, a correlation of phase shape between the first PPG signal and the second PPG signal, or a periodicity of one or more of the first PPG signal, the second PPG signal or the third PPG signal.   
     
     
         12 . The device of  claim 9 , wherein the one or more processing devices are configured to:
 determine an insulin release event using at least a first PPG signal of the plurality of PPG signals, wherein the first PPG signal is obtained from a wavelength of light in a range of 380 nm-410 nm; and   determine the one or more PPG parameters using the plurality of PPG signals obtained during the insulin release event.   
     
     
         13 . The device of  claim 9 , wherein the one or more processing devices are configured to:
 determine a first L value by isolating an alternating current (AC) component of a first PPG signal in a range of 380 nm-410 nm and a second L value by isolating an AC component of a second PPG signal at a wavelength at or above 660 nm and a third L value by isolating an AC component of a third PPG signal in a range of 510 nm-550 nm;   determine a plurality of R values using the plurality of L values, wherein a first R value is determined from a ratio of the first L value and the second L value and a second R value is determined from a ratio of the first L value and the third L value.   
     
     
         14 . The device of  claim 13 , wherein the one or more processing devices are further configured to determine the health index, wherein the health index indicates a diabetic risk in the user. 
     
     
         15 . The device of  claim 9 , wherein the one or more processing circuits implement regression neural network processing or a classifier neural network processing to determine the health index. 
     
     
         16 . A method, comprising:
 obtaining a plurality of PPG signals at a plurality of wavelengths reflected from or transmitted through tissue of a user, wherein the plurality of wavelengths have varying penetration depths of tissue;   determining one or more PPG parameters using the plurality of PPG signals; and   determining a health index using the one or more PPG parameters, wherein the health index indicates a vascular health of the user.   
     
     
         17 . The method of  claim 16 , wherein determining the one or more PPG parameters using the plurality of PPG signals comprises:
 determining at least one of the following PPG parameters: a phase delay between a first PPG signal and a second PPG signal of the plurality of PPG signals, a correlation of phase shape between the first PPG signal and the second PPG signal of the plurality of PPG signals or a periodicity of first PPG signal or the second PPG signal of the plurality of PPG signals.   
     
     
         18 . The method of  claim 16 , further comprising:
 determining at least one insulin release event using at least a first PPG signal of the plurality of PPG signals, wherein the first PPG signal is obtained from a wavelength of light in a range of 380 nm-410 nm.   
     
     
         19 . The method of  claim 18 , wherein determining the health index using the one or more PPG parameters comprises:
 determine the one or more PPG parameters using at least the first PPG signal, wherein the first PPG signal is obtained during the insulin release event.   
     
     
         20 . The method of  claim 19 , further comprising:
 determining a relative change in diameter of vessels during the insulin release event; and   determining a health index using the one or more PPG parameters and the relative change in diameter of vessels.