# US 10,481,085 B2 · Simple sugar concentration sensor and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,085 B2 - Document ID: US10481085B2 - Status: Granted - Kind: B2 - Application number: 16/031,026 - Filed: 2018-07-10 - Published: 2018-12-06 - Granted: 2019-11-19 - Earliest claimed: 2012-10-16 - Assignees: K Sciences GP, LLC - Applicants: K Sciences GP, LLC - Inventors: Valentin Korman - Web page: https://patentgrep.com/patent/US10481085B2 ## CPC - G01N 21/359: using near infrared light - A61B 5/14532: {for measuring glucose, e.g. by tissue impedance measurement} - A61B 5/1455: using optical sensors, e.g. spectral photometrical oximeters - A61B 5/14558: {by polarisation} - A61B 5/6815: {Ear} - G01N 21/21: Polarisation-affecting properties (G01N21/19 takes precedence) - G01N 21/3577: for analysing liquids, e.g. polluted water - G01N 33/49: Blood {(chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80)} - A61B 5/7225: {Details of analogue processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation (input circuits for detecting, measuring, or recording bioelectric or biomagnetic signals A61B5/30; specific diagnostic methods using bioelectric or biomagnetic signals A61B5/316)} - A61B 2560/0443: Modular apparatus - A61B 2562/0238: Optical sensor arrangements for performing transmission measurements on body tissue - G01N 2201/062: LED's - G01N 2201/0683: Brewster plate; polarisation controlling elements - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A glucose sensor comprising an optical energy source having an emitter with an emission pattern; a first polarizer intersecting the emission pattern; a second polarizer spaced a distance from the first polarizer and intersecting the emission pattern, the second polarizer rotated relative to the first polarizer by a first rotational amount Θ; a first optical detector intersecting the emission pattern; a second optical detector positioned proximal to the second polarizer, the first polarizer and the second polarizer being positioned between the optical energy source and the second optical detector, the second optical detector intersecting the emission pattern; a compensating circuit coupled to the second optical detector; and a subtractor circuit coupled to the compensating circuit and the first optical detector. ## Claims ### Claim 1 A noninvasive system for measuring glucose, the system comprising: a light source; a first polarizer illuminated by the light source and providing a first polarized light; a second polarizer illuminated by the light source and spaced apart from the first polarizer and providing a second polarized light; a first detector positioned to detect at least some or all of the first polarized light; and a second detector positioned to detect at least some or all of the second polarized light; one or more of the first detector and the second detector configured to determine a relative intensity of the first polarized light relative to the second polarized light or the second polarized light relative to the first polarized light. ### Claim 2 (depends on 1) The noninvasive system of claim 1, wherein one or more of the first polarizer and the second polarizer are a linearly polarized film. ### Claim 3 (depends on 1) The noninvasive system of claim 1, further comprising a feedback circuit connecting the light source and the first detector and configured to adjust an intensity of a light of the light source to maintain the at least some or all of the first polarized light detected by the first detector within a first portion calibration range. ### Claim 4 (depends on 3) The noninvasive system of claim 3, wherein the first portion calibration range is defined by an upper calibration threshold greater than a first target intensity value and a lower calibration threshold lesser than the first target intensity value. ### Claim 5 (depends on 1) The noninvasive system of claim 1, wherein the first polarizer and the second polarizer are differentially rotated. ### Claim 6 (depends on 1) The noninvasive system of claim 1, wherein the first polarizer is rotated a rotation with respect to the second polarizer, the rotation comprising about forty five degrees, or a multiple thereof. ### Claim 7 (depends on 1) The noninvasive system of claim 1, wherein the first polarizer is rotated a first rotation with respect to the second polarizer, the first rotation comprising about forty five degrees, or a multiple thereof, in addition to a second rotation with respect to the second polarizer, the second rotation caused by measurement of a control positioned between the first polarizer and the second polarizer to establish a baseline measurement of the system, the control being capable of being penetrated by light from the light source. ### Claim 8 (depends on 1) The noninvasive system of claim 1, wherein the first polarizer is rotated a first rotation with respect to the second polarizer, the first rotation comprising about forty five degrees, or a multiple thereof, with respect to the second polarizer, in addition to a second rotation with respect to the second polarizer, the second rotation caused by measurement of a control positioned between the first polarizer and the second polarizer to establish a baseline measurement of the system, the control comprising glucose in a concentration considered normal for a human. ### Claim 9 (depends on 5) The noninvasive system of claim 5, wherein the rotation is from 35 to 55 degrees, or a multiple thereof, and including 35 and 55 degrees, and multiples thereof. ### Claim 10 (depends on 1) The noninvasive system of claim 1, further comprising a circuit, in which a first output from the first detector, and a second output from the second detector are each provided to the circuit, the circuit comprising a Wheatstone bridge for producing at least a third output as a difference between the first output and the second output. ### Claim 11 (depends on 1) The noninvasive system of claim 1, further comprising a circuit, in which a first output from the first detector, and a second output from the second detector are each provided to the circuit, the circuit comprising an attenuator coupled to the first output. ### Claim 12 (depends on 1) The noninvasive system of claim 1, further comprising a circuit, in which a first output from the first detector, and a second output from the second detector are each provided to the circuit, the circuit comprising at least one of a subtractor for producing at least a third output as a difference between the first output and the second output, a compensator for boosting at least a portion of the second output, and a gain to amplify at least the third output. ### Claim 13 (depends on 12) The noninvasive system of claim 12, further comprising low pass filters associated with the circuit to reduce noise from the first detector and the second detector. ### Claim 14 (depends on 12) The noninvasive system of claim 12, further comprising a unity gain circuit. ### Claim 15 (depends on 1) The noninvasive system of claim 1, wherein the system is for measuring glucose in a body tissue, the body tissue positioned proximate to the first polarizer and proximate to the second polarizer, and between the first polarizer and the second polarizer. ### Claim 16 (depends on 1) The noninvasive system of claim 1, the configuring one or more of the first detector and the second detector comprising at least one of increasing, decreasing, and comparing, a first output of the first detector and a second output of the second detector. ### Claim 17 A method for measuring glucose, the method comprising: providing a light source of light; positioning a first polarizer to be illuminated by the light source and to provide a first polarized light; positioning a second polarizer to be illuminated by the light source and spaced apart from the first polarizer and to provide a second polarized light; positioning a first detector to detect at least some or all of the first polarized light, the first detector providing a first output; positioning a second detector to detect at least some or all of the second polarized light, the second detector providing a second output; and configuring one or more of the first detector and the second detector to determine a relative intensity of the first polarized light relative to the second polarized light or the second polarized light relative to the first polarized light. ### Claim 18 (depends on 17) The method of claim 17, further comprising: providing a circuit for receiving the first output and the second output, the circuit comprising at least a subtractor for producing at least a third output as a difference between the first output and the second output, a compensator for boosting at least a portion of the second output, and a gain to amplify at least the third output. ### Claim 19 (depends on 17) The method of claim 17, further comprising providing a feedback circuit connecting the light source and the first detector and configured to adjust an intensity of the light to maintain the at least some or all of the first polarized light detected by the first detector within a first portion calibration range. ### Claim 20 (depends on 17) The method of claim 17, wherein the adjusting the one or more of the first detector and the second detector is performed when providing a control proximate to the first polarizer and proximate to the second polarizer, and between the first polarizer and the second polarizer, the control having a first glucose concentration. ### Claim 21 (depends on 17) The method of claim 17, the configuring one or more of the first detector and the second detector comprising at least one of increasing, decreasing, and comparing, the first output of the first detector and the second output of the second detector. ### Claim 22 (depends on 17) The method of claim 17, wherein the configuring one or more of the first detector and the second detector is performed when providing a control, the control being proximate to the first polarizer and proximate to the second polarizer, and between the first polarizer and the second polarizer, and adjusting a potentiometer associated with the one or more of the first detector and the second detector so an intensity of the first polarized light to the first detector is similar or equal to an intensity of the second polarized light to the second detector. ### Claim 23 A noninvasive system for measuring glucose, the system comprising: a light source for emitting light; a first polarizer for receiving emitted light; a second polarizer for receiving emitted light; a first detector positioned to detect first polarized light from the first polarizer; and a second detector positioned to detect second polarized light from the second polarizer; a feedback circuit connecting the light source and the first detector and configured to adjust an intensity of the light to maintain the at least some or all of the first polarized light detected by the first detector within a first portion calibration range; and one or more of the first detector and the second detector being so adjusted that the first polarized light to the first detector is of a similar intensity as that of the second polarized light to the second detector. ### Claim 24 (depends on 23) The noninvasive system of claim 23, wherein the first polarizer and the second polarizer are differentially rotated. ### Claim 25 (depends on 23) The noninvasive system of claim 23, wherein the first polarizer is rotated a rotation with respect to the second polarizer, the rotation comprising about forty five degrees, or a multiple thereof. ### Claim 26 (depends on 23) The noninvasive system of claim 23, wherein the system is for measuring glucose in a body tissue, the body tissue positioned proximate to the first polarizer and proximate to the second polarizer. ### Claim 27 A method for measuring glucose, the method comprising: positioning a light source proximate to a first polarizer and a second polarizer in a manner that light emitting from the light source is provided to the first polarizer and the second polarizer; positioning a first detector to receive first polarized light provided by the first polarizer, the first detector providing a first output; positioning a second detector to receive second polarized light provided by the second polarizer, the second detector providing a second output; adjusting one or more of the first detector and the second detector to determine a relative intensity of the first polarized light relative to the second polarized light or the second polarized light relative to the first polarized light. ### Claim 28 (depends on 27) The method according to claim 27, wherein the first polarizer receives light directly from the light source and the second polarizer receives the first polarized light from the first polarizer. ### Claim 29 (depends on 27) The method according to claim 27, wherein the adjusting comprises adjusting, in response to the first output, an intensity of the light emitting from the light source by a feedback circuit connecting the light source and the first detector, wherein the adjusting maintains the first output within a first portion calibration range.