# US 9,039,179 B2 · Unobtrusive active eye interrogation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,039,179 B2 - Document ID: US9039179B2 - Status: Granted - Kind: B2 - Application number: 13/711,436 - Filed: 2012-12-11 - Published: 2014-06-12 - Granted: 2015-05-26 - Earliest claimed: 2012-12-11 - Assignees: Elwha LLC - Applicants: Elwha LLC - Inventors: Allen L. Brown, Jr.; Douglas C. Burger; Eric Horvitz; Roderick A. Hyde; Edward K. Y. Jung; Eric C. Leuthardt; Jordin T. Kare; Chris Demetrios Karkanias; John L. Manferdelli; Craig J. Mundie; Nathan P. Myhrvold; Barney Pell; Clarence T. Tegreene; Willard H. Wattenburg; Charles Whitmer; Lowell L. Wood, Jr.; Richard N. Zare - Web page: https://patentgrep.com/patent/US9039179B2 ## CPC - A61B 3/113: for determining or recording eye movement - A61B 3/0008: {provided with illuminating means (A61B3/117, A61B3/14 take precedence)} - A61B 3/0025: {characterised by electronic signal processing, e.g. eye models} - A61B 3/10: Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions - G06V 40/19: Sensors therefor - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract Methods and systems for determining a physiological parameter of a subject through interrogation of an eye of the subject with an optical signal are described. Interrogation is performed unobtrusively. The physiological parameter is determined from a signal sensed from the eye of a subject when the eye of the subject is properly aligned with regard to an interrogation signal source and/or response signal sensor. ## Claims ### Claim 1 A system for sensing information from an eye of a subject, comprising: a gaze signal sensor adapted for receiving a gaze signal containing information indicative of a gaze direction of the eye of the subject; an interrogation signal source for delivering the interrogation signal to the eye of the subject; a response signal sensor for sensing a response signal produced by the eye of the subject responsive to the interrogation signal; and signal processing circuitry including: a gaze signal processor configured to determine the gaze direction of the eye of the subject based upon the gaze signal; an alignment detector configured to determine whether the eye of the subject is in alignment with respect to at least one of the interrogation signal source and the response signal sensor based at least in part upon the gaze direction; and a response signal processor configured to process the response signal sensed from the eye of the subject by the response signal sensor when the eye of the subject is in alignment with respect to the at least one of the interrogation signal source and the response signal sensor to determine a physiological parameter from the response signal. ### Claim 2 A system for controlling the sensing of information from an eye of a subject, comprising: signal processing circuitry including: a gaze signal input adapted to receive a gaze signal containing information indicative of a gaze direction of the eye of the subject sensed from at least the eye of the subject; a response signal input adapted to receive a response signal sensed from the eye of the subject by a response signal sensor responsive to delivery of an interrogation signal to the eye of the subject; a gaze signal processor configured to determine the gaze direction of the eye of the subject based upon the gaze signal; an alignment detector configured to determine whether the eye of the subject is in alignment with respect to at least one of the interrogation signal source and the response signal sensor based at least in part upon the gaze direction; and a response signal processor configured to process the response signal sensed from the eye of the subject by the response signal sensor when the eye of the subject is in alignment with respect to the at least one of the interrogation signal source and the response signal sensor to determine a physiological parameter from the response signal. ### Claim 3 (depends on 1) The system of claim 1, wherein the gaze signal sensor includes at least one of a camera, an infrared camera, a CCD camera, an optical sensor, and an optical sensor array. ### Claim 4 (depends on 1) The system of claim 1, wherein the interrogation signal source includes at least one of an optical signal source, an acoustic signal source, a broad spectrum light source, a near-infrared light source, a tunable laser source, and a mid-infrared light source. ### Claim 5 (depends on 1) The system of claim 1, wherein the response signal sensor includes at least one of an optical sensor, an acoustic sensor, a spectrometer based on a CCD array, a near-infrared camera, a Raman spectrometer based on a CCD camera, a mid-infrared detector, and a broad spectrum pyroelectric detector. ### Claim 6 (depends on 1) The system of claim 1, including at least one gaze tracking stimulus source adapted to deliver a gaze tracking stimulus to at least the eye of the subject, wherein the gaze signal is produced in response to the gaze tracking stimulus, and wherein the gaze tracking stimulus source includes at least one of an infra-red source and a near infra-red source. ### Claim 7 (depends on 1) The system of claim 1, wherein the interrogation signal source is adapted to deliver a pulsed interrogation signal, and wherein the signal processing circuitry is configured to combine multiple response signals produced by the eye of the subject in response to multiple pulses of the pulsed interrogation signal by at least one of summing the multiple response signals, averaging the multiple response signals, determining a moving average of the multiple response signals, and determining a weighted sum of the multiple response signals. ### Claim 8 (depends on 1) The system of claim 1, including at least a first response signal sensor, and a second response signal sensor, wherein the interrogation signal source is adapted to deliver an interrogation signal containing multiple wavelengths of light, and wherein the first response signal sensor is configured to sense a first response signal produced by the eye of the subject responsive to a first wavelength component of the interrogation signal, and the second response signal sensor is configured to sense a second response signal produced by the eye of the subject responsive to a second wavelength component of the interrogation signal. ### Claim 9 (depends on 1) The system of claim 1, including at least a first interrogation signal source configured to deliver a first interrogation signal having a first optical wavelength and at least a second interrogation signal source configured to deliver a second interrogation signal having a second optical wavelength, wherein the signal processing circuitry is configured to process a first response signal sensed from the eye of the subject in response to the first interrogation signal and a second response signal sensed from the eye of the subject in response to the second interrogation signal by comparing the first and second response signals to determine the physiological parameter. ### Claim 10 (depends on 1) The system of claim 1, including at least one of an output structure adapted to output a signal relating to the determined physiological parameter and a display adapted to display information relating to the determined physiological parameter. ### Claim 11 (depends on 10) The system of claim 10, wherein the output structure includes at least one of a data transmission structure, a data storage structure, a display, an audio output, and a visual output. ### Claim 12 (depends on 10) The system of claim 10, wherein the display includes at least one of a video monitor, a computer display, a video game display, a telephone display, a terminal of a data processing device, a display incorporated in a wearable item, a display incorporated in an article of furniture, a display incorporated in an article of medical or health-care related equipment, a display incorporated in an article of exercise equipment and a display incorporated in a vehicle. ### Claim 13 (depends on 2) The system of claim 2, including: interrogation signal control circuitry configured to drive production of the interrogation signal by an interrogation signal source; and gaze tracking stimulus control circuitry configured to drive production of a gaze tracking stimulus by at least one gaze tracking stimulus source. ### Claim 14 (depends on 2) The system of claim 2, wherein the response signal processor is configured to process the response signal sensed from the eye of the subject by the response signal sensor when the eye of the subject is in alignment with respect to the at least one of the interrogation signal source and the response signal sensor to determine a measurement of at least one of oxygenation, blood glucose, a heart rate, glycosylated hemoglobin, a temperature, a body temperature, a blood flow, and a substance in the eye of the subject from the response signal. ### Claim 15 (depends on 2) The system of claim 2, including interrogation control circuitry configured to drive production of a pulsed interrogation signal by an interrogation signal source, and wherein the signal processing circuitry is configured to gate detection of the response signal relative to the pulsed interrogation signal. ### Claim 16 (depends on 2) The system of claim 2, including interrogation control circuitry configured to drive production of a pulsed interrogation signal by an interrogation signal source, and wherein the signal processing circuitry is configured to combine multiple response signals produced by the eye of the subject in response to multiple pulses of the pulsed interrogation signal by at least one of summing the multiple response signals, averaging the multiple response signals, determining a moving average of the multiple response signals, and determining a weighted sum of the multiple response signals. ### Claim 17 (depends on 2) The system of claim 2, including at least one of an output structure adapted to output a signal relating to the determined physiological parameter and a display adapted to display information relating to the determined physiological parameter. ### Claim 18 (depends on 1) The system of claim 1, wherein the interrogation signal source is adapted to produce light having a first polarization, wherein the response signal sensor is adapted to detect light having a second polarization, and where the first polarization and the second polarization are different. ### Claim 19 (depends on 1) The system of claim 1, wherein the interrogation signal source is adapted to produce light having a first polarization, wherein the response signal sensor is adapted to detect light having a second polarization, and where the first polarization and the second polarization are the same. ### Claim 20 (depends on 1) The system of claim 1, wherein interrogation signal source and the response signal sensor are separately co-aligned. ### Claim 21 (depends on 1) The system of claim 1, wherein interrogation signal source and the response signal sensor are separately aligned and located. ### Claim 22 (depends on 2) The system of claim 2, including gaze tracking stimulus control circuitry configured to drive production of a gaze tracking stimulus by a plurality of gaze tracking stimulus sources. ### Claim 23 (depends on 2) The system of claim 2, including interrogation signal control circuitry configured to drive production of a first interrogation signal having a first optical wavelength and production of a second interrogation signal having a second optical wavelength.