WO2015041719A1

WO2015041719A1 - In-situ tear sample collection and testing using a contact lens

Info

Publication number: WO2015041719A1
Application number: PCT/US2014/024492
Authority: WO
Inventors: Zenghe Liu; James ETZKORN
Original assignee: Google Inc.
Priority date: 2012-09-07
Filing date: 2014-03-12
Publication date: 2015-03-26
Also published as: US9320460B2; US20140194706A1; US20140192315A1

Abstract

Apparatus, systems and methods employing contact lenses having one or more sensor that sense an analyte in tear fluid and one or more recesses that collect the tear fluid. In some aspects, a contact lens includes a substrate that forms at least part of a body of the contact lens and a recess formed within the substrate configured to collect tear fluid when the contact lens is worn. The contact lens further includes at least one sensor disposed within the substrate configured to sense presence of an analyte in the collected tear fluid.

Description

IN-SITU TEAR SAMPLE COLLECTION AND TESTING

USING A CONTACT LENS

TECHNICAL FIELD

[0001] This disclosure generally relates to a contact lens employing one or more recesses integrated within a substrate that collect tear fluid and supply collected tear fluid to a sensor for sensing of an analyte therein.

BACKGROUND

[0002] Tear fluid provides a viable source of biological analytes that can indicate various health states of an individual from which tear fluid is generated. However, collection of tear samples for testing is difficult. Many processes for collecting tear samples usually irritate the eye and produce tear fluid having constituents which can lead to erroneous test results. For example, tear fluid generated from irritation of an eye, such as touching of the eye and tear fluid generated from an emotional reaction comprise different constituents than basal tears and are generally produced in greater quantity than basal tears. Such reflex and emotional tears interfere with composition of tear samples of interest.

[0003] In order to avoid some of the aforementioned drawbacks associated with collection of tear fluid, contact lenses have been established that employ internal sensing platforms for in-situ testing of tear fluid for analytes. These contact lenses generally test tear fluid that forms a tear film over the contact lens. However, the total volume of tear fluid establishing the tear film is often insufficient for in-situ testing of various analytes.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 illustrates an example contact lens having a recess for collecting tear fluid and having a sensor for sensing an analyte in the collected tear fluid in accordance with aspects described herein. [0005] FIGs. 2A and 2B illustrate additional examples of contact lenses having one or more recesses for collecting tear fluid and having a sensor for sensing an analyte in the collected tear fluid in accordance with aspects described herein.

[0006] FIG. 3A-3C illustrate examples contact lens having a plurality of recesses for collecting tear fluid and/or having a plurality of sensors for sensing one or more analytes in the collected tear fluid in accordance with aspects described herein.

[0007] FIG. 4A-4B illustrate top planar views of examples of contact lenses having a plurality of recesses for collecting tear fluid and having a sensor for sensing an analyte in the collected tear fluid in accordance with aspects described herein.

[0008] FIG. 5 presents an illustration of an exemplary non-limiting system that includes a contact lens that facilitates sensing and determining information associated with an analyte present within tear fluid generated by a wearer of the contact lens in accordance with aspects described herein.

[0009] FIG. 6 is a high level illustration of an example contact lens circuit for employment in a contact lens to facilitate gathering, processing and wirelessly communicating, sensed information related to an analyte present in tear fluid collected in a cavity disposed within the contact lens, accordance with aspects described herein

[0010] FIG. 7 presents an exemplary reader device for receiving, from a contact lens, information related to an analyte sensed in tear fluid collected by the contact lens in accordance with aspects described herein.

[0011] FIG. 8 is an exemplary flow diagram of a method that facilitates collecting tear fluid with a contact lens, and sensing an analyte in the collected tear fluid in accordance with aspects described herein.

[0012] FIG. 9 is an exemplary flow diagram of a method that facilitates collecting tear fluid with a contact lens, sensing an analyte in the collected tear fluid, and transmitting information associated with the sensed analyte in accordance with aspects described herein.

[0013] FIG. 10 is an illustration of a schematic diagram of an exemplary networked or distributed computing environment with which one or more aspects described herein can be associated.

[0014] FIG. 11 is an illustration of a schematic diagram of an exemplary computing environment with which one or more aspects described herein can be associated. DETAILED DESCRIPTION

[0015] In one or more aspects, the disclosed subject matter relates to a contact lens that facilitates in-situ tear fluid testing. In some aspects, the contact lens includes a substrate that forms at least part of a body of the contact lens and a recess formed within the substrate configured to collect tear fluid when the contact lens is worn. The contact lens further includes at least one sensor disposed within the substrate configured to sense presence of an analyte in the collected tear fluid.

[0016] In another aspect, a method is disclosed that includes collecting tear fluid in a cavity disposed within a body of a contact lens and detecting presence of at least one analyte in the collected tear fluid via at least one sensor located within the body of the contact lens. In one aspect, the at least one sensor is located within the cavity. In another aspect, the at least one sensor is located adjacent to the cavity and the cavity includes an opening through which the tear fluid contacts the at least one sensor. According to this aspect, the method can include dispensing a portion of the tear fluid from the cavity via the opening so that the portion of the tear fluid contacts the at least one sensor.

[0017] In another embodiment, a contact lens is provided having a tear fluid collection recess formed in a substrate that forms at least part of a body of the contact lens and configured to collect tear fluid when the contact lens is worn. The contact lens further includes at least one sensor configured to sense presence of one or more analytes the tear fluid and a processor configured to determines or infer type or concentration of the one or more analytes. A transmitter is also included on or within the contact lens configured to transmit information relating to type or concentration of the one or more analytes to an external device.

[0018] Various aspects are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It should be appreciated that one or more aspects of the drawings from are not drawn to scale. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a more thorough understanding of one or more aspects. It is be evident, however, that such aspects can be practiced without these specific details. In other instances, structures and devices are shown in block diagram form in order to facilitate describing one or more aspects. [0019] With reference now to the drawings, FIG. 1 illustrates a cross-sectional view of an example tear fluid collecting contact lens 100 in accordance with aspects described herein. Contact lens 100 includes a recess or cavity 106 for collecting tear fluid and having a sensor 108 for sensing an analyte in the collected tear fluid when the contact lens 100 is worn over an eye 104. As used herein the terms recess and cavity are used interchangeably. The recess 106 is configured to collect tear fluid over time as the contact lens 104 is worn over an eye. In an aspect, the recess 106 collects tear fluid via capillary action and/or osmosis. The collected tear fluid serves as a reservoir of tear fluid for analyte sensing processes of sensor 108.

[0020] In particular, tear fluid provides a viable source of biological analytes that can indicate various health states of the individual from which the tear fluid is generated. Contact lenses having integrated sensors for sensing various analytes generally test analytes present in tear fluid that forms a tear film over the contact lens. However, the total volume of tear fluid establishing the tear film is often insufficient for in-situ testing of various analytes. For example, electrochemical sensors can be employed within a contact lens that perform oxidation or reduction of an analyte of interest and measure current generated in association with oxidation or reduction. However, when ta ear film serves as a sole source of analyte, continuous sensing by an electrochemical sensor is often compromised because the limited amount of analyte in the tear film can be quickly consumed by the sensor.

[0021] Contact lens 100 is depicted having a single cavity 106. However in various aspects, contact lenses disclosed herein can include any suitable number N of cavities, N is an integer. Cavities, such as cavity 106 provided within the disclosed tear fluid collecting contact lenses, such as contact lens 100, can fill with tear fluid over a period of time dependant on size and shape of cavities. Further, tear collecting cavities provided within contact lenses disclosed herein can slowly fill with tear fluid over time so as not to dry out an eye. It is to be appreciated that the contact lens can be designed and configured to collect tear fluid over any suitable range of time (e.g., seconds, minutes, hours, days, weeks, or months). In an aspect, the cavities are configured to store collected tear fluid while the contact lens is worn in the eye, and when the contact lens is removed from the eye.

[0022] As illustrated in FIG. 1, cavity 106 and sensor 108 are located within a body or substrate 102 of the contact lens 100. In an aspect, the substrate 102 is a hydrogel - the contact lenses disclosed herein can comprise any suitable material that can be employed to create one or more tear colleting cavities within the substrate 102. In an aspect, the contact lenses disclosed herein can include soft lenses made from one or more soft polymer materials including but not limited to, a hydrogel, a silicone based hydrogel, a polyacrlyamide, or a hydrophilic polymer. For example, in an aspect, contact lenses disclosed herein can include crosslinked hydrogels including hydrophilic monomers (e.g. N-Vinylpyrrolidone, N,N-dimethylacrylamide, 2 -hydroxy ethyl methacrylate , hydroxyethyl acrylate , methacrylic acid and acrylic acid), strengthening agents, ultraviolent light (UV) blockers, or tints. In another aspect, contact lenses disclosed herein can include silicone hydrogels (e.g. crosslinked hydrogels containing silicone macromers and monomers, as well as hydrophilic monomers that absorb water). In yet another aspect, contact lenses disclosed herein can include hard lenses made from one or more rigid materials including but not limited to, a silicone polymer, polymethyl methacrylate, or rigid gas permeable materials.

[0023] Although not to be limited to such shape, the contact lenses disclosed herein, such as contact lens 100, are generally provided in a spherical shape that conforms to shape of an eye. With reference to FIG. 1, contact lens 100 include two primary surfaces, an inner surface 112 and an outer surface 1 10, both of which are spherical. The inner surface 1 12 is concave and is shown facing and resting on a surface of the eye 104, and conforming to shape of cornea 114 - the outer surface 1 10 is convex.

[0024] In an aspect, as depicted in FIG. 1, a cavity 106 is located within the substrate 102 and adjacent outer wall 1 12. According to this aspect, cavity 106 is designed to collect tear fluid disposed on the outer surface of the contact lens 102. It is to be appreciated that cavity 106 includes an opening or diffusion layer adjacent the outer surface 110 of the contact lens at which tear fluid enters via capillary action and/or osmosis respectively. In other aspects, tear collecting cavities are disposed within the substrate 102 and adjacent to the inner surface 1 12 or a perimeter edge of the contact lens 100. Regardless of location of a cavity within the substrate, the respective cavity includes an opening and/or diffusion layer adjacent to a surface of the contact lens that facilitates influx of tear fluid.

[0025] In an aspect, a cavity 106 can be located within the substrate at or near a perimeter of the substrate so that the cavity is not located in front of the cornea 114 of the eye when the contact lens in worn in the eye. According to this aspect, a cavity provided within the substrate of a contact lens can have a length slightly less than a radius (midway point R of FIG. 1) of the contact lens. However a cavity may be provided within a contact lens having a length that ranges substantially the length or diameter (dashed line D) of the substrate.

[0026] Cavities disposed within the disclosed contact lenses, such as cavity 106 of contact lens 100, can have any suitable size and shape that facilitate collection of tear fluid without irritating the eye, without disrupting the functions of the eye, without disrupting function of the contact lens, and without causing discomfort to the wearer. For example, cavity 106 can have a rectangular shape (as depicted in FIG. 1), a cylindrical shape, or a semi-ellipsoid shape. In various aspects, cavity 106 has an optimal size that facilitates collecting an amount of tear fluid for performing continuous sensing by a sensor 108 when the tear fluid is provided to the sensor 108. Accordingly, the size and shape of a cavity can vary depending on functions of sensor 108 that will be sensing the tear fluid collected within the cavity.

[0027] Contact lens 100 (and additional contact lenses described herein) has a thickness or width that spans in a horizontal direction between inner surface 1 12 and outer surface 1 10. In general aspects, the width of the lens is thickest (relative to the width of the lens at other areas of the lens) at the center point of the lens, tapering outwardly to a knifelike edge at the perimeter of the lens. Dashed line W indicates direction of the width or depth of the contact lens 100. The diameter of the contact lens 100 is indicated by dashed line D. The particular dimensions (including dimensions attributable to thickness, diameter, curvature, and etc.) of the subject contact lenses are not critical and may vary.

[0028] In an aspect, a cavity, such as cavity 106 provided within the substrate of a contact lens, such as contact lens 100, can have a depth that spans within the thickness or width W of the substrate, including the entire thickness. For example, the thickness or width of the substrate of a contact lens can range about 1.0 μιη to about 400 μιη depending on type of lens and distance from center point. Generally, contact lenses have a thickness of about 50 μιη to about 150 μιη. In typical human eyes, the tear film has a general thickness of about 7-8 μιη while the total volume of tears in an eye is about 6-8 μ With this in mind, for every ΙΟμιη of depth of a tear collecting cavity (e.g. cavity 106), available volume of tears for consumption by a sensor within the contact lens (e.g. sensor 108) can be doubled as compared to available tears in regular tear film.

[0029] In an aspect, where the substrate has a thickness of about 400 μιη, a cavity can have a width or depth of about 400 μιη or less and about 10 μιη, more particularly, a depth of about 150 μιη or less and about 25 μιη, and even more particularly, a depth of about 100 μιη or less and about 50 μιη. In another aspect, where the substrate has a thickness of about 150 μιη, a cavity can have a width or depth of about 150 μιη or less and about 10 μιη, more particularly, a depth of about 100 μιη or less and about 25 μιη, and even more particularly, a depth of about 75 μιη or less and about 50 μιη.

[0030] In an embodiment, cavities provided within the subject tear collecting contact lenses are considered microcavities. The term microcavity as used herein includes cavities, channels, cells, or other cavity capable of collecting and storing tear fluid having a volumetric size less than the entire volume of the substrate in which it is located. In an aspect, the total volume of the contact lens substrate is about 25 to about 50 micro liters. With this in mind, in an aspect, a microcavity has a volume less than about 50% of the total volume of the substrate. In another aspect, a microcavity has a volume less than about 25% of the total volume of the substrate. In another aspect, a microcavity has a volume less than about 10% of the total volume of the substrate. In yet another aspect, a microcavity has a volume less than about 5% of the total volume of the substrate. In yet another aspect, a microcavity has a volume less than about 0.1% of the total volume of the substrate. Still in yet another aspect a microcavity has a volume less than about 0.01% of the total volume of the substrate.

[0031] Referring back to FIG. 1, contact lens 100 (and additional contact lenses described herein) includes a sensor 108 configured to sense one or more analytes within tear fluid collected in cavity 106. In an aspect, as illustrated in FIG. 1, the sensor 108 is located within cavity 106. Sensor 108 and additional sensory employed in contact lenses disclosed herein, can include a variety of sensors configured to sense one or more analytes of interest. For example, sensors for employment with the disclosed contact lenses can include but are not limited to, an electrochemical sensor, a biosensor, an amperometric sensor, or a pressure sensor. Such sensors can be configured to sense information indicative of presence and/or concentration of various analytes in collected tear fluid, including but not limited to glucose, alcohol, histamine, urea, lactate, cholesterol, or electrolyte ions such as sodium, potassium, calcium and magnesium. In an aspect, sensor 108 can include two or more sensors configured to sense different analytes of interest.

[0032] Turning now to FIG. 2A presented is another cross-sectional view of an example tear fluid collecting contact lens 200 in accordance with aspects described herein. Contact lens 200 includes a recess or cavity 106 for collecting tear fluid and having a sensor 108 for sensing an analyte in the collected tear fluid when the contact lens 200 is worn over an eye 104. Repetitive description of like elements employed in respective embodiments of contact lenses described herein is omitted for sake of brevity.

[0033] Contact lens 200 is similar to contact lens 100 with the exception that sensor 108 is located within the substrate 102 yet outside of cavity 106. According to this embodiment, cavity 106 can include an opening and/or a diffusion layer 202 configured to release or excrete collected tear fluid. For example, the opening 202 can include a relatively small hole through which collected tear fluid slowly and steadily escapes cavity 106 in a controlled fashion. The size and shape of the opening 202 can be selected such that a predetermined amount of tear fluid is dispensed from cavity 106 at a predetermined rate. In aspect, rather than a hole, cavity 106 can include a diffusion layer 202 that includes a material that allows for the diffusion of tear fluid out of cavity 106. The diffusion layer material can be selected such that a predetermined amount of tear fluid is dispensed from cavity 106 at a predetermined rate.

[0034] According to this embodiment, sensor 108 is provided within the substrate 102 outside of cavity 106 and substantially adjacent to opening 108. As tear fluid is dispensed through opening 108, it contacts sensor 108. With this configuration, sensor 108 can be provided a controlled amount of fresh tear fluid at a continuous rate. In an aspect, by separating sensor 108 from the reservoir of tear fluid collected in cavity 106, by-products generated by the sensor 108 can be separated from the collected tear fluid so as to not contaminate the collected tear fluid. In addition, by providing sensor 108 with a continuous supply of fresh tear fluid, changes in the analyte composition of the tear fluid over time can be more accurately discerned.

[0035] FIG. 2B presents another cross-sectional view of an example tear fluid collecting contact lens 201 in accordance with aspects described herein. Contact lens 201 includes a recess or cavity 106 for collecting tear fluid and having a sensor 108 for sensing an analyte in the collected tear fluid when the contact lens 201 is worn over an eye 104. [0036] Contact lens 201 is similar to contact lens 100 with exception of inclusion of two or more cavities 106 provided within the substrate and disposition of cavities 106 and sensors 108 within the substrate 102. According to this embodiment, cavity 106 is disposed within the substrate 102 such that depth of the cavity spans substantially parallel with diameter D of the substrate. Cavities 106 are adjacent to outer surfaces 1 10 of the substrate 102 towards an outer perimeter of the contact lens. In particular, a cavity 106 has a width W that spans within the thickness of the substrate, substantially perpendicular to the inner 1 12 and outer 110 surfaces of the substrate, and a depth greater than the width that spans substantially parallel to the inner 112 and outer 1 10 surfaces of the substrate. With this embodiment, depth of cavity 106 can be increased to a depth greater than thickness of the substrate. It should be appreciated that cavities 106 are depicted having a rectangular shape merely for illustrative purposes, and are not to be limited to such shape or configuration. For example, cavities 106 can have a shape that substantially corresponds to the curvature of the contact lens 201. Sensors 108 can be further located within cavities 106 and adjacent to a side surface of the respective cavities.

[0037] FIG. 3A presents another cross-sectional view of an example tear fluid collecting contact lens 300 in accordance with aspects described herein. Contact lens 300 includes a plurality of cavities 304 for collecting tear fluid. Respective cavities 304 are further associated with respective sensors 108 for sensing an analyte in the collected tear fluid when the contact lens 300 is worn over an eye 104.

[0038] Contact lens 300 is depicted having eight cavities 304, however it should be appreciated that contact lens 300 can include any number N cavities. Respective cavities 304 are disposed within the substrate adjacent to outer surface 110 of the contact lens 300. According to this aspect, cavities 304 can collect tear fluid disposed on the outer surface 1 10 of the contact lens. Sensors 108 can be located within the cavities 304 and/or outside the cavities, (as depicted in FIG. 1 and 2A respectively). In an aspect, respective sensors 108 associated with the respective cavities 304 are configured to sense presence and/or concentration of different analytes. Therefore, contact lens 300 can sense information associated with a plurality of different analytes at the same time while sensing mechanisms of the respective sensors 108 do not interfere with one another. For example, by-products of a first reaction associated with a first sensor can be contained within a first cavity. As a result, the by-products of the first reaction will not interfere with sensing mechanisms of a second sensor disposed within a second cavity and configured to perform a different reaction with respect to a different analyte of interest.

[0039] FIG. 3B presents another cross-sectional view of an example tear fluid collecting contact lens 301 in accordance with aspects described herein. Contact lens 301 includes a plurality of cavities 306 for collecting tear fluid. Respective cavities 306 are further associated with respective sensors 108 for sensing an analyte in the collected tear fluid when the contact lens 301 is worn over an eye 104. Contact lens 301 is similar to contact lens 300 with exception of disposition of cavities 306 within the substrate 102. In particular, with contact lens 301, the cavities 306 are located adjacent to an inner surface 112 of the substrate 102. According to this aspect, the cavities 306 can collect tear fluid present on an inner surface 1 12 of the contact lens and/or a surface of the eye 104.

[0040] FIG. 3C presents another cross-sectional view of an example tear fluid collecting contact lens 302 in accordance with aspects described herein. Contact lens 302 includes a plurality of cavities 308 for collecting tear fluid. In one aspect, respective cavities 308 are further associated with respective sensors 108 for sensing an analyte in the collected tear fluid when the contact lens 302 is worn over an eye 104 (as depicted in the lower half of contact lens 302). In another aspect, a plurality of cavities 308 can share a single sensor 108 (as depicted in the upper half of contact lens 302).

[0041] Contact lens 302 is similar to contact lens 300 with exception of disposition of cavities 308 and/or one or more sensors 108 within the substrate 102. In particular, cavities 308 span an entire width or thickness of contact lens 302. Cavities 308 can include an opening adjacent to an inner surface 112 and/or an outer surface 110 of the substrate 102. In an aspect, as presented in the lower half of contact lens 302, a plurality of cavities 308 span the thickness of the substrate and are separated from one another by a space 310. Respective cavities 308 in the lower half of the contact lens 302 further include a sensor 108 located therein. In another aspect, as depicted in the upper half of contact lens 302, a plurality of cavities are provided adjacent to one another and span the thickness of the substrate. Further, the plurality of cavities 308 in the upper half of contact lens 302 can share a single sensor 108. In an aspect, the shared sensor is located just outside/external to the plurality of cavities. In another aspect, the shared sensor is located within the plurality of cavities 308. [0042] Referring now to FIGs. 4A and 4B, depicted are top planar views of example contact lenses 400 and 401, respectively, worn over an eye 104 in accordance with aspects described herein. In an aspect, lenses 300-302 can have top planar configurations same or similar to that depicted of lens 400. In particular, the cross- section of lens 400 taken along axis Y can resemble the cross-sections of lenses 300- 301, where the cavities 106 of lens 400 and similarly lenses 300-301 are provided having a depth/length that spans the width of the substrate (e.g. substantially perpendicular to a surface of the lens). It should be appreciate that the number of cavities 106 depicted and proportional size of the cavities shown is not limiting and is merely intended for illustrative purposes. For example, lens 400 can have any number N of cavities (where N is an integer) of varying size. The cavities 106 of lens 400 are located within the substrate 102 and are disposed a radial distance away from the center of the lens so as not to cover the cornea 114 of the eye.

[0043] With reference to FIG. 4B, presented is another top-planar view of an example tear collecting contact lens 401 in accordance with disclosed aspects. In an aspect, lens 401 demonstrates a potential top planar configuration of contact lens 201. In particular, the cross-section of lens 401 taken along axis Y can resemble the cross-section of lens 202, where the cavities 106 of lens 401 and similarly lens 202, are provided having a depth/length that spans a length of the substrate (e.g. substantially parallel to a surface of the lens). It should be appreciated that number of cavities 106 depicted and proportional size of the cavities depicted (e.g. eight) is not limiting and is merely intended for illustrative purposes. For example, lens 401 can have any number N of cavities (where N is an integer) of varying size. The cavities 106 of lens 401 are located within the substrate 102 and are disposed a radial distance away from the center of the lens so as not to cover the cornea of the eye (e.g. the pupil 1 12 and the iris 114). In an aspect, cavities 106 can have respective openings 402 at an outer edge/perimeter 404 of the lens 401.

[0044] With reference now FIG. 5, presented is a depiction of system 500 that includes a contact lens 501 that facilitates sensing and determining information associated with an analyte present within tear fluid generated by a wearer of the contact lens 501 in accordance with aspects described herein. Contact lens 501 covers at least a portion of an eye 104. Contact lens 501 includes one or more recesses 502 configured to collect tear fluid and one or more sensors 504 configured to sense presence and/or concentration of an analyte of interest in the collected tear fluid. Repetitive description of like elements employed in respective embodiments of contact lenses described herein, such as sensors and/or recesses is omitted for sake of brevity.

[0045] Contact lens 501 further includes a contact lens circuit 506 that facilitates sensing functions of the one or more sensors 504, analyzing information sensed by the one or more sensors 504, and wirelessly communicating information associated with information sensed by the one or more sensors 504. One or more components of contact lens circuit 506 can be communicatively coupled to the one more sensors 504 (e.g. using one or more wires and/or chemically). Contact lens circuit 506 is described in greater detail with reference to FIG. 6.

[0046] In an aspect, contact lens circuit 506 includes various electrical and/or machine based components that facilitate gathering information sensed by the one or more sensors 504, analyzing the information, and/or transmitting the information to an external reader device 510. In an aspect, the contact lens circuit 506 includes at least a communication component (not shown) configured to wirelessly transmit data associated with information sensed by the one or more sensors 504. For example, such information can include data indicating presence and/or concentration of an analyte present within tear fluid generated by the wearer of lens 501 and collected in the one or more cavities 502. In an aspect, the communication component can include an antenna, such as a radio frequency (RF) antenna configured to transmit the information using a radio wave. In another aspect, the communication component can include one or more LEDs configured to transmit the information using light signals.

[0047] FIG. 6 is a high level illustration of example contact lens that facilitates gathering, processing and wirelessly communicating, sensed information related to an analyte present in tear fluid collected in a cavity disposed within the contact lens, accordance with aspects described herein. Repetitive description of like elements employed in respective embodiments of contact lenses and contact lens circuits described herein is omitted for sake of brevity.

[0048] As shown in FIG. 6, contact lens 501 can include one or more sensors 660 and one or more tear fluid collection cavities 670. Contact lens 501 further includes contact lens circuit 602. Contact lens circuit can include communication component 610, circuitry 620, power source 630, processor 640, and memory 650. In various embodiments, one or more of the sensors 660, communication component 610, circuitry 620, power source 630, processor 640, and memory 650 can be electrically or chemically coupled to one another to perform one or more functions of the contact lens circuit 501. For example, one or more wires can connect the components of contact lens circuit 602 and the one or more sensors 660.

[0049] In an embodiment, aspects of contact lens circuit 602 constitute machine- executable components embodied within machine(s), e.g., embodied in one or more computer readable mediums (or media) associated with one or more machines. Such components, when executed by the one or more machines, e.g., computer(s), computing device(s), virtual machine(s), etc. can cause the machine(s) to perform the operations described. Contact lens circuit can include memory 650 for storing computer executable components and instructions. Processor 640 can facilitate operation of the computer executable components and instructions by contact lens circuit 602.

[0050] As discussed above, contact lens circuit can include a communication component 610 to facilitate sending and receiving wireless communications regarding sensing of an analyte within tear fluid collected in the one or more tear fluid collection cavities. For example, the communication component can include a receiver, a transmitter, a transceiver and/or a transducer. In an aspect, the communication component 610 includes an RF antenna that transmits and receives data regarding sensing of an analyte within tear fluid collected in the one or more tear fluid collection cavities.

[0051] In particular, the one or more sensors 660 are configured to sense information indicative of presence and/or concentration of an analyte of interest found within tear fluid collected in the one or more tear fluid collection cavities. Communication component 610 can include a transducer that converts sensed information (e.g. electrical signals) at the one or more sensors into a wireless transmittable signal representative of the sensed information. For example, where a sensor includes an electrochemical sensor, the sensed information can include an electrical signal having a voltage amplitude and/or time component representative of an amount of analyte present in tear fluid as determined over a period of time. The transducer and or a transmitter can further transmit the wireless signal to device external to contact lens 501 for processing thereof.

[0052] In an aspect, the communication component 610 can transmit information related to a sensed analyte in response to a request. According to this aspect, the communication component 610 can include a receiver that wirelessly receives a request for information related to a sensed analyte. The contact lens 501 can perform sensing of analytes in collected tear fluid and store any sensed information in memory. In response to a request, the transmitter can transmit requested information.

[0053] In various aspects, sensed signals captured by the one or more sensors 660 are wirelessly transmitted to an external device for subsequent processing thereof. However, in another aspect, contact lens circuit 602 performs on board processing of sensed signals. Accordingly rather than transmitting signals representative of raw data related to a sensed analyte (e.g. voltage amplitude signals generated by the one or more sensor where the one or more sensor are electrical sensors), processor 640 can process the raw data signals. In particular, processor can process signals generated by the one or more sensors to make various determinations and inferences based on the signals. In turn, communication component can transmit processed information relating to the various determinations or inferences.

[0054] In an aspect, processor 640 is configured to determine presence and/or concentration of a sensed analyte based on signals generate by the one or more sensors. In another aspect, processor 640 can determine changes in concentration of a sensed analyte over a period of time, such as throughout the day as the contact lens 501 is worn. Still in yet other aspect, processor 640 can determine and/or infer various health states of the wearer of the contact lens 501 based on a determined concentration of a sensed analyte.

[0055] In order to processes information generated by the one or more sensors, in an aspect, sensed signals can be stored in memory 650. Further, memory 650 can store various look-up tables and/or algorithms relating sensed information to analyte concentration and/or health states. For example, the look-up tables and/or algorithms can relate voltage amplitudes and durations to an analyte concentration, such as glucose. These algorithms and/or look-up tables can further relate analyte concentration, such as glucose concentration, to a health state, such as low blood sugar. In some aspects, where the one or more sensors 660 receive a steady flow of fresh tear fluid over the course of wear of contact lens 501 (e.g. as discussed with respect to FIG. 2A), memory 650 can store a log of the fluctuations in a sensed analyte throughout the course of the wear of the contact lens. According to this aspect, for example, memory can store a log of a wearer's glucose concentration. In turn, processor 640 can determine information related to fluctuations in a wearer's blood sugar level throughout the day.

[0056] In an embodiment, processor 640 can employ various (explicitly or implicitly trained) classification schemes or systems (e.g., support vector machines, neural networks, expert systems, Bayesian belief networks, fuzzy logic, data fusion engines, etc.) in connection with performing analysis of sensed signals at the one or more sensors 660. A classifier can map an input attribute vector, x = (xl, x2, x3, x4..., xri), to a confidence that the input belongs to a class, such as by f(x) = confidence(class). Such classification can employ a probabilistic or statistical-based analysis (e.g., factoring into the analysis utilities and costs) to prognose or infer a state of a retina. A support vector machine (SVM) is an example of a classifier that can be employed. The SVM operates by finding a hyper-surface in the space of possible inputs, where the hyper-surface attempts to split the triggering criteria from the non-triggering events. Intuitively, this makes the classification correct for testing data that is near, but not identical to training data. Other directed and undirected model classification approaches include, e.g., naive Bayes, Bayesian networks, decision trees, neural networks, fuzzy logic models, and probabilistic classification models providing different patterns of independence can be employed. Classification as used in this disclosure also is inclusive of statistical regression that is utilized to develop models of priority.

[0057] Contact lens circuit 501 can additionally include the appropriate circuitry 6200 to facilitate the functions of contact lens circuit. For example, circuitry can facilitate the transfer of electrical responses received at the one or more sensor 660 to the communication component 610, memory 650, and/or processor 640. Circuitry 620 can also include signal processing hardware and software, (e.g. amplifiers, modulators, and etc.) for processing electrical signals received at the one or more sensor 660 for wireless transmission thereof.

[0058] Further, contact lens circuit 602 can include a power source 630. Power source 630 can include any suitable power source that can provide necessary power for the operation of various components of the contact lens circuit 602. For example, the power source 630 can include but is not limited to a battery, a capacitor, a solar power source, or a mechanically derived power source (e.g., MEMs system).

[0059] In an aspect, contact lens circuit 602 does not require an onboard (e.g. on the contact lens 501) power source to operate. In one aspect, contact lens circuit 602 can receive power via wireless energy transfer (e.g. using electromagnetic inductance techniques and related components).

[0060] FIG. 7 is an illustration of an exemplary non-limiting reader device 700 that interfaces with a contact lens to receive information related to a sensed analyte in accordance with aspects described herein. In various aspects, the reader device 500 can include one or more of the structure and/or functionality of reader device 510 (and vice versa).

[0061] As shown in FIG. 7, reader device 700 can include interface component 710, analysis component 720, display component 730 and request component 740. Aspects of device 700 constitute machine-executable components embodied within machine(s), e.g., embodied in one or more computer readable mediums (or media) associated with one or more machines. Such components, when executed by the one or more machines, e.g., computer(s), computing device(s), virtual machine(s), etc. can cause the machine(s) to perform the operations described. Device 700 can include memory 760 for storing computer executable components and instructions. A processor 750 can facilitate operation of the computer executable components and instructions by device 700.

[0062] Interface component 710 interfaces with and receives from at least one contact lens, data relating to a sensed analyte. In particular, interface component 710 can interface with contact lenses described herein that comprise a contact lens circuit such as contact lens circuit 602 and the like. In an aspect, interface component 610 employs a receiving component, such as an RF receiver, transceiver, photodetector, or IR receiver, to receive sensed and/or determined information from a contact lens comprising a contact lens circuit as described herein. In some aspects, interfacing component 710 can receive determined or inferred information relating to concentration of a sensed analyte. According to this aspect, the contact lens can include appropriate circuitry and components to process data sensed by one or more sensors provided on or within the contact lens.

[0063] In another aspect, the reader can receive raw data from a contact lens relating to signals sensed at one or more sensor disposed within the contact lens. For example, the interface component 610 can receive signals indicating an amplitude and duration of an electrical signal generated by the one or more sensors. According to this embodiment, the reader 700 includes an analysis component 720 that can analyze received raw data to determine or infer information related to the sensed analyte. [0064] Analysis component 720 can employ same or similar functionality described with reference to processor 640. In particular, analysis component 720 can determine and/or infer concentration of a sensed analyte and/or various health states of the wearer of the contact lens from which raw data information was transmitted based on a determined concentration of the sensed analyte. In order to processes information generated by the one or more sensors, in an aspect, received signals can be stored in memory 760. Further, memory 760 can store various look-up tables and/or algorithms relating sensed information to analyte concentration and/or health states.

[0065] Reader 700 can further include display component. In an aspect, display component generates a display corresponding to received sensor signals and/or determined or inferred analyte concentration/health state information. For example, display component 730 can include a display screen (e.g., a liquid crystal display screen (LCD)), that presents information to a user. For example, display component 730 can present a graphical display of fluctuation in concentration of a sensed analyte over course of wear of the contact lens. Reader 700 can further include request component 540 configured to generate a request for sensed analyte signals and/or determined or inferred information relating to sensed analyte signals. According to this aspect, the interface component 710 can include a transmitter that can transmit requests to the contact lens. In an aspect, the transmitter is an RF transmitter and transmits the instructions via a radio wave. According to this aspect, the instructions can include a data signal that can be received and interpreted by a contact lens communication component.

[0066] FIGs. 8-9 illustrates methodologies or flow diagrams in accordance with certain aspects of this disclosure. While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, the disclosed subject matter is not limited by the order of acts, as some acts can occur in different orders and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology can alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all illustrated acts may be required to implement a methodology in accordance with the disclosed subject matter. Additionally, it is to be appreciated that the methodologies disclosed in this disclosure are capable of being stored on an article of manufacture to facilitate transporting and transferring such methodologies to computers or other computing devices.

[0067] Referring now to FIG. 8, presented is a flow diagram of an example application of systems and apparatuses disclosed in this description in accordance with an embodiment. In an aspect, in exemplary methodology 800, a contact lens such as those described herein (e.g. 501 and the like) is employed to sense information pertaining to an analyte concentration provided in collected tear fluid. At 810, tear fluid is collected in a cavity disposed within a bode of a contact lens (e.g., using tear fluid collection cavity 670). At 820, presence of the at least one analyte in the collected tear fluid is detected via at least one sensor located within the body of the contact lens (e.g., using sensor(s) 660).

[0068] Turning now to FIG. 9, presented is another flow diagram of an example application of systems and apparatuses disclosed in this description in accordance with an embodiment. In an aspect, in exemplary methodology 900, a contact lens such as those described herein (e.g., 501 and the like) is employed to sense information pertaining to an analyte concentration provided in collected tear fluid. At 910, tear fluid is collected in a cavity disposed within a bode of a contact lens (e.g., using tear fluid collection cavity 670). At 920, a portion of the tear fluid is dispensed for the cavity via an opening in the cavity. At 930, presence of the at least one analyte in the collected tear fluid is detected via at least one sensor located within the body of the contact lens and adjacent to the opening (e.g., using sensor(s) 660). At 940, data related to the at least one analyte is transmitted to a remote device (e.g., using communication component 610).

EXEMPLARY NETWORKED AND DISTRIBUTED ENVIRONMENTS

[0069] FIG. 10 provides a schematic diagram of an exemplary networked or distributed computing environment with which one or more aspects described in this disclosure can be associated. The distributed computing environment includes computing objects 1010, 1012, etc. and computing objects or devices 1020, 1022, 1024, 1026, 1028, etc., which can include programs, methods, data stores, programmable logic, etc., as represented by applications 1030, 1032, 1034, 1036, 1038. It can be appreciated that computing objects 1010, 1012, etc. and computing objects or devices 1020, 1022, 1024, 1026, 1028, etc. can include different devices, such as active contact lenses (and components thereof), personal digital assistants (PDAs), audio/video devices, mobile phones, MPEG-1 Audio Layer 3 (MP3) players, personal computers, laptops, tablets, etc.

[0070] Each computing object 1010, 1012, etc. and computing objects or devices 1020, 1022, 1024, 1026, 1028, etc. can communicate with one or more other computing objects 1010, 1012, etc. and computing objects or devices 1020, 1022, 1024, 1026, 1028, etc. by way of the communications network 1040, either directly or indirectly. Even though illustrated as a single element in FIG. 10, network 1040 can include other computing objects and computing devices that provide services to the system of FIG. 10, and/or can represent multiple interconnected networks, which are not shown.

[0071] In a network environment in which the communications network/bus 1040 can be the Internet, the computing objects 1010, 1012, etc. can be Web servers, file servers, media servers, etc. with which the client computing objects or devices 1020, 1022, 1024, 1026, 1028, etc. communicate via any of a number of known protocols, such as the hypertext transfer protocol (HTTP).

EXEMPLARY COMPUTING DEVICE

[0072] As mentioned, advantageously, the techniques described in this disclosure can be associated with any suitable device. It is to be understood, therefore, that handheld, portable and other computing devices (including active contact lens having circuitry or components that compute and/or perform various functions). As described, in some aspects, the device can be the contact lens (or components of the contact lens) and/or the reader described herein. In various aspects, the data store can include or be included within, any of the memory described herein, any of the contact lenses described herein and/or the reader device described herein. In various aspects, the data store can be any repository for storing information transmitted to or received from the contact lens.

[0073] FIG. 1 1 illustrates an example of a suitable computing system environment 1 100 in which one or aspects of the aspects described in this disclosure can be implemented. Components of computer 1 110 can include, but are not limited to, a processing unit 1 120, a system memory 1130, and a system bus 1 122 that couples various system components including the system memory to the processing unit 1 120.

[0074] Computer 1 110 typically includes a variety of computer readable media and can be any available media that can be accessed by computer 1 110. The system memory 1 130 can include computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM) and/or random access memory (RAM). By way of example, and not limitation, memory 1130 can also include an operating system, application programs, other program components, and program data.

[0075] A user can enter commands and information into the computer 1 110 through input devices 1140 (e.g., keyboard, keypad, a pointing device, a mouse, stylus, touchpad, touch screen, motion detector, camera, microphone or any other device that allows the user to interact with the computer 11 10). A monitor or other type of display device can be also connected to the system bus 1 122 via an interface, such as output interface 1150. In addition to a monitor, computers can also include other peripheral output devices such as speakers and a printer, which can be connected through output interface 1 150.

[0076] The computer 1 110 can operate in a networked or distributed environment using logical connections to one or more other remote computers, such as remote computer 1 160. The remote computer 1 160 can be a personal computer, a server, a router, a network PC, a peer device or other common network node, or any other remote media consumption or transmission device, and can include any or all of the elements described above relative to the computer 1 110. The logical connections depicted in FIG. 1 1 include a network 1170, such local area network (LAN) or a wide area network (WAN), but can also include other networks/buses e.g., cellular networks.

[0077] Computing devices typically include a variety of media, which can include computer-readable storage media and/or communications media, in which these two terms are used herein differently from one another as follows. Computer-readable storage media can be any available storage media that can be accessed by the computer, can be typically of a non-transitory nature, and can include both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer-readable storage media can be implemented in connection with any method or technology for storage of information such as computer-readable instructions, program components, structured data, or unstructured data. Computer-readable storage media can include, but are not limited to, RAM, ROM, electrically erasable programmable read only memory (EEPROM), flash memory or other memory technology, or other tangible and/or non-transitory media which can be used to store desired information. Computer-readable storage media can be accessed by one or more local or remote computing devices, e.g., via access requests, queries or other data retrieval protocols, for a variety of operations with respect to the information stored by the medium. In various aspects, the computer-readable storage media can be, or be included within, the memory, contact lens (or components thereof) or reader described herein.

[0078] On the other hand, communications media typically embody computer-readable instructions, data structures, program components or other structured or unstructured data in a data signal such as a modulated data signal, e.g., a carrier wave or other transport mechanism, and includes any information delivery or transport media. The term "modulated data signal" or signals refers to a signal that has one or more of its characteristics set or changed in such a manner as to encode information in one or more signals.

[0079] It is to be understood that the aspects described in this disclosure can be implemented in hardware, software, firmware, middleware, microcode, or any combination thereof. For a hardware aspect, the processing units can be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors and/or other electronic units designed to perform the functions described in this disclosure, or a combination thereof.

[0080] For a software aspect, the techniques described in this disclosure can be implemented with components or components (e.g., procedures, functions, and so on) that perform the functions described in this disclosure. The software codes can be stored in memory units and executed by processors.

[0081] What has been described above includes examples of one or more aspects. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned aspects, but one of ordinary skill in the art can recognize that many further combinations and permutations of various aspects are possible. Accordingly, the described aspects are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims.

[0082] Moreover, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless specified otherwise, or clear from the context, the phrase "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, the phrase "X employs A or B" is satisfied by any of the following instances: X employs A; X employs B; or X employs both A and B. In addition, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from the context to be directed to a singular form.

[0083] The aforementioned systems have been described with respect to interaction between several components. It can be appreciated that such systems and components can include those components or specified sub-components. Sub-components can also be implemented as components communicatively coupled to other components rather than included within parent components (hierarchical). Additionally, it is to be noted that one or more components can be combined into a single component providing aggregate functionality. Any components described in this disclosure can also interact with one or more other components not specifically described in this disclosure but generally known by those of skill in the art.

[0084] In view of the exemplary systems described above methodologies that can be implemented in accordance with the described subject matter will be better appreciated with reference to the flowcharts of the various figures. While for purposes of simplicity of explanation, the methodologies are shown and described as a series of blocks, it is to be understood and appreciated that the claimed subject matter is not limited by the order of the blocks, as some blocks can occur in different orders and/or concurrently with other blocks from what is depicted and described in this disclosure. Where nonsequential, or branched, flow is illustrated via flowchart, it can be appreciated that various other branches, flow paths, and orders of the blocks, can be implemented which achieve the same or a similar result. Moreover, not all illustrated blocks may be required to implement the methodologies described in this disclosure after.

[0085] In addition to the various aspects described in this disclosure, it is to be understood that other similar aspects can be used or modifications and additions can be made to the described aspect(s) for performing the same or equivalent function of the corresponding aspect(s) without deviating there from. Still further, multiple processing chips or multiple devices can share the performance of one or more functions described in this disclosure, and similarly, storage can be provided across a plurality of devices. The invention is not to be limited to any single aspect, but rather can be construed in breadth, spirit and scope in accordance with the appended claims.

Claims

CLAIMS What is claimed is:

1. A contact lens, comprising:

a substrate that forms at least part of a body of the contact lens;

a recess formed within the substrate, configured to collect tear fluid when the contact lens is worn; and

at least one sensor disposed within the substrate configured to sense presence of an analyte in the collected tear fluid.

2. The contact lens of claim 1, further comprising, a plurality of recesses formed within the substrate configured to collect tear fluid when the contact lens is worn.

3. The contact lens of claim 1 , wherein the recess is formed at or about a perimeter of the contact lens.

4. The contact lens of claim 1, wherein the recess has a depth spanning about a thickness of a cross-sectional area of the substrate.

5. The contact lens of claim 4, wherein the recess has a depth within a range of about 50 to about 400 μιη.

6. The contact lens of claim 1, wherein the recess has a depth within a range of about 10 to about 75 μιη.

7. The contact lens of claim 1, wherein the at least one sensor is located within the recess.

8. The contact lens of claim 1, wherein the at least one sensor is located adjacent to the recess and wherein the recess includes an opening through which the tear fluid contacts the at least one sensor.

9. The contact lens of claim 1, wherein the recess collects the tear fluid via capillary action.

10. The contact lens of claim 1, wherein at least one sensor is an electrochemical sensor.

1 1. The contact lens of claim 1, comprising a transmitter configured to transmit data relating to a sensed analyte in the tear fluid.

12. The contact lens of claim 1, comprising a processor configured to determine or infer type or concentration of a sensed analyte in the tear fluid.

13. A method comprising:

collecting tear fluid in a cavity disposed within a body of a contact lens; and

detecting presence of at least one analyte in the collected tear fluid via at least one sensor located within the body of the contact lens.

14. The method of claim 13, comprising transmitting data relating to a detected analyte in the tear fluid.

15. The method of claim 13, comprising determining or inferring type or concentration of a sensed analyte in the tear fluid.

16. The method of claim 15, further comprising dispensing a portion of the tear fluid from the cavity via the opening so that the portion of the tear fluid contacts the at least one sensor.

17. The method of claim 13, wherein the collecting the tear fluid comprises collecting the tear fluid in the cavity via capillary action.

18. The method of claim 15, further comprising transmitting data related to the type or concentration of the sensed analyte to a remote device.

19. A contact lens, comprising:

a tear fluid collection recess formed in a substrate that forms at least part of a body of the contact lens and configured to collect tear fluid when the contact lens is worn;

at least one sensor configured to sense presence of one or more analytes the tear fluid;

a processor configured to determine or infer type or concentration of the one or more analytes; and

a transmitter configured to transmit information relating to the type or the concentration of the one or more analytes to an external device.

20. The contact lens of claim 19, further comprising a memory that stores information relating to the type or the concentration of the one or more analytes.