# US 10,117,587 B2 · Dynamically reconfigurable apertures for optimization of PPG signal and ambient light mitigation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,117,587 B2 - Document ID: US10117587B2 - Status: Granted - Kind: B2 - Application number: 15/139,133 - Filed: 2016-04-26 - Published: 2016-10-27 - Granted: 2018-11-06 - Earliest claimed: 2015-04-27 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Chin San Han - Web page: https://patentgrep.com/patent/US10117587B2 ## CPC - A61B 5/02427: {Details of sensor} - A61B 5/14552: {Details of sensors specially adapted therefor} - A61B 5/681: {Wristwatch-type devices} - A61B 5/6898: {Portable consumer electronic devices, e.g. music players, telephones, tablet computers} - A61B 5/7214: {using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths} - A61B 2560/0252: using ambient temperature - A61B 2562/0238: Optical sensor arrangements for performing transmission measurements on body tissue - A61B 2562/0242: for varying or adjusting the optical path length in the tissue - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract This relates to an electronic device with dynamically reconfigurable apertures to account for different skin types, usage conditions, and environmental conditions and methods for measuring the user's physiological signals. The device can include one or more light emitters, one or more light sensors, and a material whose optical properties can be changed in one or more locations to adjust the optical path and the effective separation distances between the one or more light emitters and one or more light sensors or the size, location, or shape of the one or more dynamically reconfigurable apertures. In some examples, the material can be a liquid crystal material, MEMS shutter layer, or light guide, which can form the one or more dynamically reconfigurable apertures. In some examples, the light emitters or light sensors or both can be an array of individually addressable optical components. ## Claims ### Claim 1 An electronic device for measuring physiological information, the device comprising: one or more light emitters configured to emit light; one or more light sensors configured to detect a reflection of the emitted light and generate one or more signals indicative of the detected reflected light; a device component capable of forming dynamically reconfigurable apertures having a configuration to allow light to be transmitted from at least one of the one or more light emitters to at least one of the one or more light sensors, each aperture including a center location; and a processor configured to: dynamically adjust a separation distance between the center locations of at least two of the apertures; and determine the physiological information based on the one or more signals. ### Claim 2 (depends on 1) The electronic device of claim 1, wherein the electronic device is capable of dynamically reconfiguring one or more of a size of the apertures, a location of the apertures, and a shape of the apertures. ### Claim 3 (depends on 1) The electronic device of claim 1, wherein the one or more light sensors includes at least two light sensors capable of sensing different wavelengths. ### Claim 4 (depends on 1) The electronic device of claim 1, wherein the one or more light emitters includes at least two light emitters capable of emitting at different wavelengths. ### Claim 5 (depends on 3, 4) The electronic device of claim 3 or claim 4, wherein: wherein a sensing wavelength of at least one of the one or more light sensors or an emission wavelength of at least one of the one or more light emitters and separation distance associated with a second configuration is longer than a sensing wavelength of the at least one of the one or more light sensors or an emission wavelength of the at least one of the one or more light emitters and separation distance, respectively, associated with a first configuration. ### Claim 6 (depends on 1) The electronic device of claim 1, wherein the processor is further configured to: change one or more optical properties of the device component to form the apertures. ### Claim 7 (depends on 6) The electronic device of claim 6, wherein the device component comprises a liquid crystal layer capable of forming the apertures. ### Claim 8 (depends on 6) The electronic device of claim 6, wherein the device component comprises a plurality of microelectromechanical (MEMS) shutters capable of forming the apertures. ### Claim 9 (depends on 6) The electronic device of claim 6, wherein the one or more optical properties of the device component are different in a location corresponding to the center locations than a location outside of the apertures. ### Claim 10 (depends on 1) The electronic device of claim 1, wherein the one or more light emitters are formed from an array of individually addressable light emitters. ### Claim 11 (depends on 1) The electronic device of claim 1, wherein the one or more light sensors are formed from an array of individually addressable light sensors. ### Claim 12 (depends on 1) The electronic device of claim 1, further comprising at least one optical filter, wherein at least one of the one or more light emitters is a broadband source coupled to the at least one optical filter. ### Claim 13 (depends on 1) The electronic device of claim 1, wherein the device component comprises a light guide configured to receive at least one of the emitted light and the reflected light. ### Claim 14 (depends on 13) The electronic device of claim 13, wherein at least one of the emitted light and the reflected light enters or exits the light guide in a location different from a location corresponding to the one or more light emitters or the one or more light sensors. ### Claim 15 (depends on 13) The electronic device of claim 13, wherein the light guide is located on a same layer as at least one of the one or more light emitters and the one or more light sensors. ### Claim 16 (depends on 1) The electronic device of claim 1, wherein the one or more light emitters are located on a different layer than the one or more light sensors. ### Claim 17 An electronic device for measuring physiological information, the device comprising: one or more light emitters configured to emit light; one or more light sensors configured to detect a reflection of the emitted light and generate one or more signals indicative of the detected reflected light; and a device component capable of forming dynamically reconfigurable apertures having a configuration to allow light to be transmitted from at least one of the one or more light emitters to at least one of the one or more light sensors, a processor configured to: determine the physiological information based on the one or more signals; wherein: during a first configuration: the one or more light emitters are configured to emit a first light, the one or more light sensors are configured to receive a second light, the second light being a reflection of the first light, and the apertures, each having a center location, are configured to: allow the first light to be transmitted from the one or more light emitters, and allow the second light to be received at the one or more light sensors; and during a second configuration: the one or more light emitters are configured to emit a third light, the one or more light sensors are configured to receive a fourth light, the fourth light being a reflection of the third light, the apertures are configured to: allow the third light to be transmitted from the one or more light emitters, and allow the fourth light to be received at the one or more light sensors; and wherein the processor is further configured to compare a signal from the second light to a signal from the fourth light and dynamically adjust a separation distance between the center locations of the apertures from the first configuration to the second configuration. ### Claim 18 (depends on 17) The electronic device of claim 17, wherein the processor is further configured to: determine a PPG signal from the first configuration; and determine a perfusion index from the second configuration. ### Claim 19 (depends on 17) The electronic device of claim 17, wherein the processor is further configured to: dynamic reconfigure the apertures one or more of a different size of the apertures, a different location of the apertures, and a different shape of the apertures. ### Claim 20 (depends on 17) The electronic device of claim 17, wherein the apertures of the second configuration block light at a location of the first light emitted by the one or more light emitters during the first configuration, and the apertures of the first configuration block light at a location of the third light emitted by the one or more light emitters during the second configuration. ### Claim 21 (depends on 17) The electronic device of claim 17, wherein the apertures are configured with a third configuration, the third configuration based on the compared signals and being one of the configurations used in the comparison. ### Claim 22 (depends on 17) The electronic device of claim 17, wherein the first configuration is associated with a first determination of aperture size, location, and shape, and the second configuration is associated with a second determination of aperture size, location, and shape, wherein the first determination is coarser than the second determination. ### Claim 23 (depends on 17) The electronic device of claim 17, wherein the apertures are capable of being dynamically reconfigured from the first configuration to the second configuration during an initial calibration procedure. ### Claim 24 (depends on 17) The electronic device of claim 17, wherein the processor is further configured to: control a voltage of a liquid crystal material to dynamically reconfigure the apertures. ### Claim 25 (depends on 17) The electronic device of claim 17, wherein the device component includes a plurality of individual sections, wherein the processor is further configured to control each individual section. ### Claim 26 (depends on 25) The electronic device of claim 25, further comprising: a plurality of electrodes, wherein the processor is further configured to apply a voltage difference to control the plurality of individual sections to dynamically change one or more of a size, number, location, and shape of the apertures. ### Claim 27 (depends on 17) The electronic device of claim 17, further comprising: a window located at or near an external housing of the electronic device, wherein an active area of the one or more light emitters and an active area of the one or more light sensors face the external housing, and the device component is located proximate to the window. ### Claim 28 (depends on 17) The electronic device of claim 17, further comprising: an optical component layer including the one or more light emitters and the one or more light sensors. ### Claim 29 (depends on 17) The electronic device of claim 17, wherein the one or more light emitters are located on a different layer than the one or more light sensors.