AUGMENTED REALITY PULSE OXIMETRY

• US 20160287153A1
• Filed: 03/16/2016
• Published: 10/06/2016
• Est. Priority Date: 03/16/2015
• Status: Active Grant

• Current Assignee: Magic Leap, Inc.
• Original Assignee: Magic Leap, Inc.
• Inventors: Samec, Nicole Elizabeth, Kaehler, Adrian
• Granted Patent: US 11,022,797 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0204 Acoustic sensors
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 3/0008 provided with illuminating means A61B3/117 takes precedence; goniolenses used for laser treatment A61F9/009; illuminating means for optical instruments G02B27/00
• CPC Class Codes: A61B 3/0025 characterised by electronic signal processing, e.g. eye models
• CPC Class Codes: A61B 3/005 Constructional features of the display
• CPC Class Codes: A61B 3/022 for testing contrast sensitivity
• CPC Class Codes: A61B 3/024 for determining the visual field, e.g. perimeter types
• CPC Class Codes: A61B 3/028 for testing visual acuity; for determination of refraction, e.g. phoropters
• CPC Class Codes: A61B 3/0285 Phoropters
• CPC Class Codes: A61B 3/032 Devices for presenting test symbols or characters, e.g. test chart projectors A61B3/036 takes precedence
• CPC Class Codes: A61B 3/036 for testing astigmatism
• CPC Class Codes: A61B 3/063 for testing light sensitivity, i.e. adaptation
• CPC Class Codes: A61B 3/066 for testing colour vision
• CPC Class Codes: A61B 3/08 for testing binocular or stereoscopic vision, e.g. strabismus
• CPC Class Codes: A61B 3/085 for testing strabismus
• CPC Class Codes: A61B 3/10 Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
• CPC Class Codes: A61B 3/1005 for measuring distances inside the eye, e.g. thickness of the cornea A61B3/11 takes precedence
• CPC Class Codes: A61B 3/101 for examining the tear film
• CPC Class Codes: A61B 3/1015 for wavefront analysis
• CPC Class Codes: A61B 3/102 : for optical coherence tomography [OCT]
• CPC Class Codes: A61B 3/1035 : for measuring astigmatism testing astigmatism A61B3/036
• CPC Class Codes: A61B 3/113 : for determining or recording eye movement
• CPC Class Codes: A61B 3/12 : for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: A61B 3/1216 : for diagnostics of the iris
• CPC Class Codes: A61B 3/1241 : specially adapted for observation of ocular blood flow, e.g. by fluorescein angiography
• CPC Class Codes: A61B 3/13 : Ophthalmic microscopes
• CPC Class Codes: A61B 3/14 : Arrangements specially adapted for eye photography apparatus or arrangements for taking photographs per se G03B
• CPC Class Codes: A61B 3/165 : Non-contacting tonometers
• CPC Class Codes: A61B 5/0059 : using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0066 : Optical coherence imaging
• CPC Class Codes: A61B 5/0077 : Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/01 : Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/12 : Audiometering
• CPC Class Codes: A61B 5/14532 : for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 : using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14555 : specially adapted for the eye fundus
• CPC Class Codes: A61B 5/361 : Detecting fibrillation
• CPC Class Codes: A61B 5/369 : Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/398 : Electrooculography [EOG], e.g. detecting nystagmus; Electroretinography [ERG]
• CPC Class Codes: A61B 5/6803 : Head-worn items, e.g. helmets, masks, headphones or goggles
• CPC Class Codes: A61B 8/10 : Eye inspection
• CPC Class Codes: A61B 8/461 : Displaying means of special interest
• CPC Class Codes: A61F 2007/0004 : Eyes or part of the face surrounding the eyes
• CPC Class Codes: A61F 2007/004 : Hip
• CPC Class Codes: A61F 2009/00863 : Retina
• CPC Class Codes: A61F 9/0026 : Ophthalmic product dispenser attachments to facilitate positioning near the eye
• CPC Class Codes: A61H 2201/165 : Wearable interfaces
• CPC Class Codes: A61M 2021/0022 : by the tactile sense, e.g. vibrations
• CPC Class Codes: A61M 2021/0027 : by the hearing sense
• CPC Class Codes: A61M 2021/0066 : with heating or cooling
• CPC Class Codes: A61M 21/02 : for inducing sleep or relaxation, e.g. by direct nerve stimulation, hypnosis, analgesia for massage A61H; electrotherapy A61N, e.g. applying alternating or intermittent electric currents for producing anaesthesia A61N1/36021
• CPC Class Codes: A61M 2205/3375 : Acoustical, e.g. ultrasonic, measuring means
• CPC Class Codes: A61M 2205/507 : Head Mounted Displays [HMD]
• CPC Class Codes: A61N 2005/0648 : the light being directed to the eyes
• CPC Class Codes: G02B 2027/0138 : comprising image capture systems, e.g. camera
• CPC Class Codes: G02B 2027/014 : comprising information/image processing systems
• CPC Class Codes: G02B 2027/0185 : Displaying image at variable distance
• CPC Class Codes: G02B 21/0032 : Optical details of illumination, e.g. light-sources, pinholes, beam splitters, slits, fibers G02B21/0036 - G02B21/008; means for illumination of specimens in general G02B21/06
• CPC Class Codes: G02B 27/0093 : with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/0172 : characterised by optical features
• CPC Class Codes: G02B 27/0179 : Display position adjusting means not related to the information to be displayed
• CPC Class Codes: G02C 7/027 : considering wearer's parameters
• CPC Class Codes: G06T 19/006 : Mixed reality object pose determination, tracking or camera calibration for mixed reality G06T7/00
• CPC Class Codes: G06T 2207/10024 : Color image
• CPC Class Codes: G06T 2207/10148 : Varying focus
• CPC Class Codes: G06T 2207/10152 : Varying illumination
• CPC Class Codes: G06T 2207/30041 : Eye; Retina; Ophthalmic
• CPC Class Codes: G16H 20/17 : delivered via infusion or injection
• CPC Class Codes: G16H 40/63 : for local operation
• CPC Class Codes: G16H 40/67 : for remote operation
• CPC Class Codes: G16H 50/20 : for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

One embodiment is directed to a system comprising a head-mounted member removably coupleable to the user'"'"'s head; one or more electromagnetic radiation emitters coupled to the head-mounted member and configured to emit light with at least two different wavelengths toward at least one of the eyes of the user; one or more electromagnetic radiation detectors coupled to the head-mounted member and configured to receive light reflected after encountering at least one blood vessel of the eye; and a controller operatively coupled to the one or more electromagnetic radiation emitters and detectors and configured to cause the one or more electromagnetic radiation emitters to emit pulses of light while also causing the one or more electromagnetic radiation detectors to detect levels of light absorption related to the emitted pulses of light, and to produce an output that is proportional to an oxygen saturation level in the blood vessel.

Claims

1. A system for determining oxygen saturation of a user, comprising:

a. a head-mounted member removably coupleable to the user'"'"'s head;

b. one or more electromagnetic radiation emitters coupled to the head-mounted member and configured to emit light with at least two different wavelengths in the visible to infrared spectrum in direction of at least one of the eyes of the user;

c. one or more electromagnetic radiation detectors coupled to the head-mounted member and configured to receive light reflected after encountering at least one blood vessel of the eye of the user; and

d. a controller operatively coupled to the one or more electromagnetic radiation emitters and one or more electromagnetic radiation detectors and configured to cause the one or more electromagnetic radiation emitters to emit pulses of light while also causing the one or more electromagnetic radiation detectors to detect levels of light absorption related to the emitted pulses of light, and to produce an output that is proportional to an oxygen saturation level in the blood vessel.

2. The system of claim 1, wherein the head-mounted member comprises an eyeglasses frame.

3. The system of claim 2, wherein the eyeglasses frame is a binocular eyeglasses frame.

4. The system of claim 1, wherein the one or more radiation emitters comprises a light emitting diode.

5. The system of claim 4, wherein the one or more radiation emitters comprises a plurality of light emitting diodes configured to emit electromagnetic radiation at two predetermined wavelengths.

6. The system of claim 5, wherein the plurality of light emitting diodes are configured to emit electromagnetic radiation at a first wavelength of about 660 nanometers, and a second wavelength of about 940 nanometers.

7. The system of claim 5, wherein the one or more radiation emitters are configured to emit electromagnetic radiation at the two predetermined wavelengths sequentially.

8. The system of claim 5, wherein the one or more radiation emitters are configured to emit electromagnetic radiation at the two predetermined wavelengths simultaneously.

9. The system of claim 1, wherein the one or more electromagnetic radiation detectors comprises a device selected from the group consisting of:

a photodiode, a photodetector, and a digital camera sensor.

10. The system of claim 1, wherein the one or more electromagnetic radiation detectors is positioned and oriented to receive light reflected after encountering at least one blood vessel of the retina of the eye of the user.

11. The system of claim 1, wherein the one or more electromagnetic radiation detectors is positioned and oriented to receive light reflected after encountering at least one blood vessel of the sclera of the eye of the user.

12. The system of claim 6, wherein the controller is further configured to cause the plurality of light emitting diodes to emit a cyclic pattern of first wavelength on, then second wavelength on, then both wavelengths off, such that the one or more electromagnetic radiation detectors detect the first and second wavelengths separately.

13. The system of claim 12, wherein the controller is configured to cause the plurality of light emitting diodes to emit a cyclic pattern of first wavelength on, then second wavelength on, then both wavelengths off, in a cyclic pulsing pattern about thirty times per second.

14. The system of claim 12, wherein the controller is configured to calculate a ratio of first wavelength light measurement to second wavelength light measurement, and wherein this ratio is converted to an oxygen saturation reading via a lookup table based at least in part upon the Beer-Lambert law.

15. The system of claim 14, wherein the controller is configured to operate the one or more electromagnetic radiation emitters and one or more electromagnetic radiation detectors to function as a head-mounted pulse oximeter.

16. The system of claim 15, wherein the controller is operatively coupled to an optical element coupled to the head-mounted member and viewable by the user, such that the output of the controller that is proportional to an oxygen saturation level in the blood vessel of the user may be viewed by the user through the optical element.

17. The system of claim 9, wherein the one or more electromagnetic radiation detectors comprises a digital image sensor comprising a plurality of pixels, and wherein the controller is configured to automatically detect a subset of pixels which are receiving the light reflected after encountering at least one blood vessel of the eye of the user, and to use such subset of pixels to produce the output that is proportional to an oxygen saturation level in the blood vessel.

18. The system of claim 17, wherein the controller is configured to automatically detect the subset of pixels based at least in part upon reflected light luminance differences amongst signals associated with the pixels.

19. The system of claim 17, wherein the controller is configured to automatically detect the subset of pixels based at least in part upon reflected light absorption differences amongst signals associated with the pixels.