# US 2014/0194706 A1 · In-situ tear sample collection and testing using a contact lens > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0194706 A1 - Document ID: US20140194706A1 - Status: Published application - Kind: A1 - Application number: 14/030,756 - Filed: 2013-09-18 - Published: 2014-07-10 - Earliest claimed: 2012-09-07 - Assignees: Google Inc. - Applicants: Google Inc. - Inventors: Zenghe Liu; James Etzkorn - Web page: https://patentgrep.com/patent/US20140194706A1 ## CPC - A61B 5/14507: {specially adapted for measuring characteristics of body fluids other than blood (devices for taking samples of body liquids A61B10/0045)} - A61B 3/101: {for examining the tear film} - A61B 5/6821: {Eye} - A61B 5/14532: {for measuring glucose, e.g. by tissue impedance measurement} - A61B 2010/0067: {Tear or lachrymal fluid} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## 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. ## Claims ### Claim 1 A contact lens, comprising: a substrate that forms at least part of a body of the contact lens, the contact lens having a concave surface and a convex surface opposite the concave surface, wherein the concave surface is configured to be removably mounted over a corneal surface of an eye; a recess formed within the substrate and having an opening in the convex surface of the contact lens, 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. ### Claim 2 (depends on 1) 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. ### Claim 3 (depends on 1) The contact lens of claim 1, wherein the recess is formed at or about a perimeter of the contact lens. ### Claim 4 (depends on 1) The contact lens of claim 1, wherein the recess has a depth spanning about a thickness of a cross-sectional area of the substrate. ### Claim 5 (depends on 4) The contact lens of claim 4, wherein the recess has a depth within a range of about 50 to about 400 μm. ### Claim 6 (depends on 1) The contact lens of claim 1, wherein the recess has a depth within a range of about 10 to about 75 μm. ### Claim 7 (depends on 1) The contact lens of claim 1, wherein the at least one sensor is located within the recess. ### Claim 8 (depends on 1) The contact lens of claim 1, the at least one sensor is located adjacent to the recess and wherein the recess includes an opening through which the tear fluid is dispensed and contacts the at least one sensor. ### Claim 9 (depends on 1) The contact lens of claim 1, wherein the recess collects the tear fluid via capillary action. ### Claim 10 (depends on 1) The contact lens of claim 1, wherein the at least one sensor is an electrochemical sensor. ### Claim 11 (depends on 1) The contact lens of claim 1, comprising a transmitter configured to transmit data relating to a sensed analyte in the tear fluid. ### Claim 12 (depends on 1) The contact lens of claim 1, comprising a processor configured to determine a concentration of a sensed analyte in the tear fluid. ### Claim 13 A method comprising: collecting tear fluid in a cavity disposed within a body of a contact lens, the contact lens having a concave surface and a convex surface opposite the concave surface, wherein the concave surface is configured to be removably mounted over a corneal surface of an eye, and the cavity having an opening in the convex surface of the 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. ### Claim 14 (depends on 13) The method of claim 13, comprising transmitting data relating to a detected analyte in the tear fluid. ### Claim 15 (depends on 13) The method of claim 13, comprising determining a concentration of a sensed analyte in the tear fluid. ### Claim 16 (depends on 13) The method of claim 13, further comprising dispensing a portion of the tear fluid from the cavity via an opening so that the portion of the tear fluid contacts the at least one sensor. ### Claim 17 (depends on 13) The method of claim 13, wherein the collecting the tear fluid comprises collecting the tear fluid in the cavity via capillary action. ### Claim 18 (depends on 15) The method of claim 15, further comprising transmitting data related to the type or concentration of the sensed analyte to a remote device. ### Claim 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, the contact lens having a concave surface and a convex surface opposite the concave surface, wherein the concave surface is configured to be removably mounted over a corneal surface of an eye; the recess further having an opening in the convex surface of the contact lens and being configured to collect tear fluid when the contact lens is worn; at least one sensor configured to sense presence of one or more analytes in the tear fluid; a processor configured to determine a concentration of the one or more analytes; and a transmitter configured to transmit information relating to the concentration of the one or more analytes to an external device. ### Claim 20 (depends on 19) 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.