PATENT DOCUMENT

Publication Number: US-11349063-B2
Application Number: US-201815986643-A
Country: US
Kind Code: B2

Title: Multi-element piezo sensor for in-bed physiological measurements

Abstract:
Disclosed herein are monitoring systems and sensors for physiological measurements. The sensors can be multi-element piezo sensors capable of generating multiple electrical signals, whereby the monitoring systems can receive the multiple electrical signals to analyze the user&#39;s vital signs along multiple regions of the user&#39;s body. In some examples, the piezo sensor can include one or more corrugations, such as peaks and valleys, to create localized regions with increased mechanical response to force. The sensitivity and resolution of the piezo sensor can be enhanced by further locating electrode sections at the corrugations, where the electrode sections can be electrically isolated and independently operable from other electrode sections. Traces electrically connecting an electrode section to, e.g., an off-panel controller can be routed over and/or around other electrode sections by including an insulator to electrically insulate from the other electrode sections, or by using vias to route through one or more layers.

Claims:
What is claimed is: 
     
       1. A multi-element piezo sensing device comprising:
 a mat for placement on a sleeping surface between a user and the sleeping surface; and 
 an array of piezoelectric sensors positioned across the mat, wherein piezoelectric sensors of the array of piezoelectric sensors comprise:
 a piezo film including a plurality of corrugations defining a set of peaks and a set of valleys, each corrugation separated from another corrugation by a section, wherein each corrugation has a higher mechanical response to an external force than surrounding sections, the plurality of corrugations configured to deform in response to the external force; 
 a plurality of electrodes comprising:
 a first set of electrodes including different electrodes electrically coupled to different peaks in the set of peaks; and 
 a second set of electrodes including different electrodes electrically coupled to different valleys in the set of valleys; and 
 
 
 a controller configured to:
 receive first signals from the first set of electrodes of multiple piezoelectric sensors in the array of piezoelectric sensors during a first sampling period; 
 receive second signals from the second set of electrodes of multiple piezoelectric sensors in the array of piezoelectric sensors during a second sampling period; and 
 determine a physiological parameter of the user using the first signals and the second signals. 
 
 
     
     
       2. The multi-element piezo sensing device of  claim 1 , wherein at least one of the plurality of electrodes is a single electrode configured to electrically couple to multiple corrugations. 
     
     
       3. The multi-element piezo sensing device  claim 1 , wherein the plurality of electrodes are configured as a plurality of electrode sections, each pair of electrode sections electrically coupled to a corrugation separate from other pairs of electrode sections, each pair of electrode sections electrically isolated from other pairs of electrode sections. 
     
     
       4. The multi-element piezo sensing device of  claim 1 , wherein:
 the piezo film includes at least one via, 
 the plurality of corrugations includes at least one peak and at least one valley, and 
 at least one routing trace electrically couples the at least one peak to the at least one valley and is routed through the at least one via. 
 
     
     
       5. The multi-element piezo sensing device of  claim 1 , further comprising:
 a second piezo film; and 
 a second electrode configured to electrically couple to the second piezo film, 
 wherein at least one of the plurality of electrodes is further configured to electrically couple to the second piezo film. 
 
     
     
       6. The multi-element piezo sensing device of  claim 1 , wherein the plurality of corrugations of the piezo film includes at least one peak and at least one valley, the multi-element piezo sensing device further comprising:
 a second piezo film including a second plurality of corrugations, the second plurality of corrugations including:
 at least one peak corresponding to the at least one peak of the piezo film, and at least one valley corresponding to the at least one valley of the piezo film; and 
 a second plurality of electrodes, wherein some of the second plurality of electrodes electrically couple to the piezo film, and others of the second plurality of electrodes electrically couple to the second piezo film. 
 
 
     
     
       7. The multi-element piezo sensing device of  claim 6 , wherein the some of the second plurality of electrodes are located on a side of the piezo film, and the others of the second plurality of electrodes are located on an opposite side of the piezo film. 
     
     
       8. The multi-element piezo sensing device of  claim 7 , further comprising:
 a plurality of electrode sections, each electrode section located between adjacent corrugations. 
 
     
     
       9. The multi-element piezo sensing device of  claim 1 , further comprising:
 a plurality of structures configured to transfer force from an external surface of the multi-element piezo sensing device to the plurality of corrugations, each structure located between the external surface and one of the plurality of corrugations. 
 
     
     
       10. A multi-element piezo sensing device comprising:
 a mat for placement on a sleeping surface between a user and the sleeping surface; and 
 an array of piezoelectric sensors positioned across the mat, wherein piezoelectric sensors of the array of piezoelectric sensors comprise:
 a piezoelectric film element defining multiple corrugations each having a peak and a valley, each corrugation separated by an intermediate section, the multiple corrugations configured to generate higher mechanical response as compared to the intermediate section in response to an applied force; 
 a plurality of electrodes comprising:
 a first set of electrodes including different electrodes electrically coupled to different peaks of the multiple corrugations; and 
 a second set of electrodes including different electrodes electrically coupled to different valleys of the multiple corrugations; and 
 
 
 a controller configured to:
 receive first signals from the first set of electrodes of multiple piezoelectric sensors in the array of piezoelectric sensors during a first sampling period; 
 receive second signals from the second set of electrodes of multiple piezoelectric sensors in the array of piezoelectric sensors during a second sampling period; and 
 determine a physiological parameter of the user using the first signals and the second signals. 
 
 
     
     
       11. The multi-element piezo sensing device of  claim 10 , wherein:
 a first electrode coupled to a first side of the piezoelectric film element; and 
 a second electrode coupled to a second side of the piezoelectric film element. 
 
     
     
       12. The multi-element piezo sensing device of  claim 11 , further comprising a via that electrically couples the first electrode to the second electrode. 
     
     
       13. The multi-element piezo sensing device of  claim 11 , wherein the first and second electrodes are coupled to a first peak of a first corrugation of the multiple corrugations. 
     
     
       14. The multi-element piezo sensing device of  claim 11 , further comprising third and fourth electrodes, wherein:
 the third electrode is coupled to a first side of a second peak of a second corrugation of the multiple corrugations; and 
 the fourth electrode is coupled to a second side of the second peak. 
 
     
     
       15. The multi-element piezo sensing device of  claim 14 , further comprising an insulator coupled to the piezoelectric film element, wherein the insulator electrically isolates the first electrode from the third electrode. 
     
     
       16. The multi-element piezo sensing device of  claim 6 , wherein an electrode of the first set of electrodes is separated from an electrode of the second set of electrodes by an insulator.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. Provisional Patent Application No. 62/509,657, filed on May 22, 2017, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     This relates generally to monitoring systems and sensors for measuring physiological measurements. 
     BACKGROUND OF THE DISCLOSURE 
     Traditionally, monitoring a user&#39;s sleep and/or measuring the user&#39;s vital signs required expensive and bulky equipment. Some systems require that the monitoring be performed away from home in a medical facility and/or require the equipment to attach to or directly contact the person, which can lead to discomfort and can lead to inaccurate analysis due to disruption of the user&#39;s sleep. Some systems can be more user-friendly by way of portability, indirect contact, etc., but these systems are configured to determine the vital signs based on one type of measurement, signal, and/or mode of operation. With a single type of measurement, signal, and/or mode of operation, the sensitivity of these systems can lead to inaccurate and/or insufficient information, thereby rendering any analysis regarding the user&#39;s sleep and vital signs ineffective. 
     SUMMARY OF THE DISCLOSURE 
     Disclosed herein are monitoring systems and sensors for physiological measurements. The sensors can be multi-element piezo sensors capable of generating multiple electrical signals, whereby the monitoring systems can receive the multiple electrical signals to analyze the user&#39;s vital signs along multiple regions of the user&#39;s body. In some examples, the piezo sensor can include one or more corrugations, such as peaks and valleys, to create localized regions with increased mechanical response (e.g., sensitivity) to force. The sensitivity and resolution of the piezo sensor can be enhanced by further locating electrode sections at the corrugations, where the electrode sections can be electrically isolated and independently operable from other electrode sections. Traces electrically connecting an electrode section to, e.g., an off-panel controller can be routed over and/or around other electrode sections by including an insulator to electrically insulate from the other electrode sections, or by using vias to route through one or more layers. The multi-element piezo sensor can include multiple piezo films and multiple pairs of electrodes (and/or electrode sections). 
     Examples of the disclosure also include piezo sensors having multiple piezo film elements, where the force (e.g., stress) can be concentrated onto the piezo film elements. Each piezo film element can be structurally and electrically isolated from other piezo film elements. Force concentration can be performed by configuring one or more intermediate layers to have a tapered profile, including one or more structures to transfer the force to the piezo film elements, configuring one or more intermediate layers to have regions of different force concentration, or a combination thereof. Examples of the disclosure further include piezo sensors configured for converting one type of force into another type of force by Poisson conversion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exemplary block diagram of a monitoring system according to examples of the disclosure. 
         FIG. 2A  illustrates a top view of an exemplary mat including a single element piezo sensor according to examples of the disclosure. 
         FIG. 2B  illustrates a top view of an exemplary mat including multi-element piezo sensors according to examples of the disclosure. 
         FIG. 2C  illustrates an exemplary method for configuring the piezo sensors included in the mat according to examples of the disclosure. 
         FIG. 3  illustrates an exemplary piezo sensor including a piezo film according to examples of the disclosure. 
         FIG. 4A  illustrates a cross-sectional view of an exemplary piezo sensor including corrugations according to examples of the disclosure. 
         FIG. 4B  illustrates a cross-sectional view of an exemplary piezo sensor including corrugations coupled to electrode sections according to examples of the disclosure. 
         FIG. 4C  illustrates an exemplary method for operating a corrugated piezo sensor including electrically isolated electrode sections according to examples of the disclosure. 
         FIG. 4D  illustrates a cross-sectional view of an exemplary piezo sensor including corrugations and electrically coupled electrode sections according to examples of the disclosure. 
         FIG. 5A  illustrates a cross-sectional view of an exemplary piezo sensor including multiple layers according to examples of the disclosure. 
         FIG. 5B  illustrates a cross-sectional view of an exemplary piezo sensor including a single electrode located across corrugations according to examples of the disclosure. 
         FIG. 5C  illustrates a cross-sectional view of an exemplary piezo sensor including an electrode section located between corrugations according to examples of the disclosure. 
         FIG. 6A  illustrates a cross-sectional view of an exemplary piezo sensor including multiple piezo film elements, the piezo sensor configured for force concentration according to examples of the disclosure. 
         FIG. 6B  illustrates a cross-sectional view of an exemplary piezo sensor including multiple piezo film elements and one or more structures, the piezo sensor configured for force concentration according to examples of the disclosure. 
         FIG. 6C  illustrates a cross-sectional view of an exemplary piezo sensor including multiple piezo film elements connected by a film layer, the piezo sensor configured for force concentration according to examples of the disclosure. 
         FIG. 6D  illustrates an exemplary piezo sensor including intermediate layers having regions of differing force concentration according to examples of the disclosure. 
         FIG. 6E  illustrates an exemplary piezo sensor including a corrugated piezo film and one or more structures, the piezo sensor configured for force concentration according to examples of the disclosure. 
         FIG. 6F  illustrates an exemplary method for operating a piezo sensor including a plurality of piezo film elements according to examples of the disclosure. 
         FIG. 7  illustrates an exemplary piezo sensor configured to convert forces by Poisson conversion according to examples of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of examples, reference is made to the accompanying drawings in which it is shown by way of illustration specific examples that can be practiced. It is to be understood that other examples can be used and structural changes can be made without departing from the scope of the various examples. 
     Various techniques and process flow steps will be described in detail with reference to examples as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects and/or features described or referenced herein. It will be apparent, however, to one skilled in the art, that one or more aspects and/or features described or referenced herein may be practiced without some or all of these specific details. In other instances, well-known process steps and/or structures have not been described in detail in order to not obscure some of the aspects and/or features described or referenced herein. 
     Further, although process steps or method steps can be described in a sequential order, such processes and methods can be configured to work in any suitable order. In other words, any sequence or order of steps that can be described in the disclosure does not, in and of itself, indicate a requirement that the steps be performed in that order. Further, some steps may be performed simultaneously despite being described or implied as occurring non-simultaneously (e.g., because one step is described after the other step). Moreover, the illustration of a process by its depiction in a drawing does not imply that the illustrated process is exclusive of other variations and modification thereto, does not imply that the illustrated process or any of its steps are necessary to one or more of the examples, and does not imply that the illustrated process is preferred. 
     Disclosed herein are monitoring systems and sensors for physiological measurements. The sensors can be multi-element piezo sensors capable of generating multiple electrical signals, whereby the monitoring systems can receive the multiple electrical signals to analyze the user&#39;s vital signs along multiple regions of the user&#39;s body. In some examples, the piezo sensor can include one or more corrugations, such as peaks and valleys, to create localized regions with increased mechanical response (e.g., sensitivity) to force. The sensitivity and resolution of the piezo sensor can be enhanced by further locating electrode sections at the corrugations, where the electrode sections can be electrically isolated and independently operable from other electrode sections. Traces electrically connecting an electrode section to, e.g., an off-panel controller can be routed over and/or around other electrode sections by including an insulator to electrically insulate from the other electrode sections or by using vias to route through one or more layers. The multi-element piezo sensor can include multiple piezo films and multiple pairs of electrodes (and/or electrode sections). 
     Examples of the disclosure also include piezo sensors having multiple piezo film elements, where the force (e.g., stress) can be concentrated onto the piezo film elements. Each piezo film element can be structurally and electrically isolated from other piezo film elements. Force concentration can be performed by configuring one or more intermediate layers to have a tapered profile, including one or more structures to transfer the force to the piezo film elements, configuring one or more intermediate layers to have regions of different force concentration, or a combination thereof. Examples of the disclosure further include piezo sensors configured for converting one type of force into another type of force by Poisson conversion. 
       FIG. 1  illustrates an exemplary block diagram of a monitoring system according to examples of the disclosure. System  199  can include mat  102 , power source  103 , camera  108 , and control system  140 . Mat  102  can be resting on, attached to, or in contact with a bed (not shown), for example. Although the discussion below is directed to a mat in contact with a bed, examples of the disclosure include other types of apparatuses configured to be in contact with one or more human users, one or more pets, or the like. That is, the mat can be in direct contact with the human(s)/pet(s), or the mat can be in contact with one or more intermediate layers, which directly contact the human(s)/pet(s). For example, mat  102  can be included in the user&#39;s clothing and can be configured for physiological measurements when the clothing is worn by the user. Mat  102  can be configured to cover all or a portion of a mattress, for example, that can be resting on, attached to, or supported by one or more frames of the bed. In some examples, mat  102  can be flexible. In some examples, mat  102  can be at least partially rigid. Mat  102  can include one or more of a sheet, blanket, duvet, pillow, pillowcase, or insert. Mat  102  can be a stand-alone unit that can be placed on a bed and can be incorporated into the fabric or textile used as part of a sleeping/resting arrangement. 
     Power source  103  can be configured to provide power to mat  102 , control system  140 , camera  108 , or any combination thereof. In some examples, power source  103  can be coupled to a power outlet. In some examples, power source  103  can be coupled to a battery and a charging station or power supply. In some examples, power source  103  can be configured to receive power from a charging element, such as a magnetic puck. In some examples, the charging element can include an inductive coil, and power can be transferred to system  199  via an electromagnetic field. 
     System  199  can include camera  108  and control system  140 . Camera  108  can be a video camera configured to perform one or more functionalities, including, but not limited to, determining the position of the user&#39;s body, determining the location of the user&#39;s body, determining the temperature of the user&#39;s body, and determining the temperature of the local ambient. The monitoring system can be configured to utilize the information from camera  108  in conjunction with the information from the one or more sensors (e.g., piezo sensors) for physiological measurements (e.g., heart rate measurements), analysis (e.g., sleep analysis), and feedback. 
     Control system  140  can be configured to control one or more parameters. For example, control system  140  can include temperature sensors  139 , which can measure and provide information to the control system  140  about the temperature of the room that system  199  is located in. In some examples, control system  140  can be configured to communicate with mat  102  through wired (e.g., using a cable) or wireless communications. Control panel  140  can include a touch panel and/or a display and can be configured to interface with the user and/or a computer. For example, control panel  140  can display heart rate, heart rate variability, respiratory rate, respiratory rate variability, user&#39;s motion, and user&#39;s temperature. In some examples, control panel  140  can display analysis regarding the user&#39;s sleep and/or can provide suggestions to improve the user&#39;s sleep. 
     Mat  102  can include one or more sensors such as piezo sensors  134 , temperature sensors  138 , and accelerometers  142 . The sensors can include one or more functionalities and configurations discussed below. Although  FIG. 1  illustrates mat  102  as including three different types of sensors, examples of the disclosure can include a monitoring system that includes fewer or more sensors and/or different types of sensors (e.g., electrodes configured for impedance cardiography (ICG), electrocardiogram (ECG), and/or ballistocardiograph (BCG) measurements). 
     While control system  140  can be included in system  199 , examples of the disclosure can include any arrangement where control system  140  is separate and distinct from system  199 . System  199  can communicate information (e.g., physiological measurements, raw data from the piezo sensors, etc.) to control system  140  through wired or wireless (e.g., local area network) communication means. In some examples, control system  140  can include a transceiver to receive information and a controller or processor to process the information for the analysis (e.g., to determine heart rate, heart rate variability, respiratory rate, and respiratory rate variability). 
       FIG. 2A  illustrates a top view of an exemplary mat including a single element piezo sensor according to examples of the disclosure. Mat  200  can include piezo sensor  230 . Piezo sensor  230  can include a polymer film (e.g., polyvinylidene fluoride (PVDF), copolymers with trifluoroethylene (P(VDF-TrFE)), poly-L-lactic acid (PLLA)) and an insulator located between a pair of electrodes, where the polymer film, insulator, and electrodes can cover the entire surface of the piezo sensor  230 , thereby forming a single element piezo sensor. In some examples, the area of the polymer film, insulator, and electrodes can be the same. 
     The measurement accuracy and sensitivity can be enhanced by using multiple piezo sensors, which can be independently operable.  FIG. 2B  illustrates a top view of an exemplary mat including multi-element piezo sensors according to examples of the disclosure. Mat  202  can include a plurality of piezo sensors  232 , piezo sensors  234 , and piezo sensors  236 . Piezo sensors  232 , piezo sensors  234 , and piezo sensors  236  can be multi-element piezo sensors, discussed in more detail below. In some examples, piezo sensors  232 , piezo sensors  234 , and piezo sensors  236  can be the same type of sensors. Mat  202  can be capable of discerning between sensors located directly under the body of user  298 , sensors located in the immediate periphery of the body of user  298 , and sensors located elsewhere. As illustrated in the figure, piezo sensors  234  can be located directly under the body of user  298 . Piezo sensors  236  can be located in the immediate periphery (i.e., adjacent to the sensors, such as piezo sensors  234 , located directly under the body of user  298 ). Piezo sensors  232  can be located elsewhere (e.g., in the periphery of mat  202 ). In some examples, one or more sensors can be located in both the immediate periphery of the body of user  298  and the periphery of mat  202 . In some examples, the monitoring system can be configured to generate a two- or three-dimensional image representing the user&#39;s position, orientation, and/or body force. 
     By having the capability to discern between sensors located in different regions of mat  202 , the monitoring system can correlate certain signals (from the piezo sensors) with certain regions of the user&#39;s body, thereby enhancing the accuracy of the measurement, analysis, and feedback to the user. For example, sensors (e.g., piezo sensors  236 ) located in the immediate periphery of the user&#39;s body can be more sensitive to gross motion of user  298  than sensors located directly under user  298 . The monitoring system can correlate the signals from piezo sensors  234  with motion of the user&#39;s chest cavity, for example. On the other hand, motion detected by sensors (e.g., piezo sensors  232 ) located elsewhere (e.g., in the periphery of mat  202 ) may not be due to the motion of user  298 . Instead, for example, the motion can be due to a second user, and the system can correlate the signals from piezo sensors  232  with the motion of the second user rather than mistakenly associating the signals to the first user (e.g., user  298 ). Additionally, the capability of discerning between sensors located in different regions can help the monitoring system differentiate between gross motion and fine body movements. For example, although a user&#39;s breathing can cause a motion artifact, the breathing motion can differ from gross motion (e.g., due to the user moving or stirring). The system can distinguish between motion due to the user breathing and motion due to the user moving. 
     In some examples, the monitoring system can be capable of determining and dynamically configuring which piezo sensors are associated with the position and orientation of the user&#39;s body. Additionally or alternatively, the monitoring system can be capable of dynamically changing the modality of a given piezo sensor.  FIG. 2C  illustrates an exemplary method for configuring piezo sensors included in a mat according to examples of the disclosure. The monitoring system can perform a first scan of all of the piezo sensors (step  252  of process  250 ). The first scan can be, for example, a high-level scan to determine roughly where the user is located along the mat (step  254  of process  250 ). The monitoring system can perform a second scan of one or more piezo sensors, such as piezo sensors potentially located in the immediate periphery of the user&#39;s body (step  256  of process  250 ). The piezo sensors that are potentially located in the immediate periphery of the user&#39;s body can be, for example, those piezo sensors measuring a force, while also located adjacent to piezo sensors that do not measure force. In some examples, the granularity of the second scan can be greater than the granularity of the first scan. In some examples, the second scan can include measuring a fewer number of piezo sensors than the first scan. The monitoring system can associate the piezo sensors according to the different locations of the user&#39;s body (step  258  of process  250 ). Optionally, the monitoring system can perform subsequent scans with increased granularity at one or more regions of the mat. The monitoring system can generate an image representing the user&#39;s location, orientation, and/or body force (step  260  of process  250 ). 
     The piezo sensors included in the monitoring system can be any type of piezo sensors including, but not limited to, piezoelectric or piezoresistive sensors. The piezo sensors can include piezo films made of, for example, PVDF, P(VDF-TrFE), and/or PLLA. The piezo sensors can be arranged to contact the user&#39;s body and can be configured to detect mechanical distortions at the external surface of the piezo sensor (e.g., interface of the mat and the user&#39;s body). Movement of the user&#39;s body (e.g., chest cavity) due to blood flow to the heart and/or respiration in the lungs can cause mechanical distortions or deformations at the external surface of the piezo sensor. The mechanical distortions or deformations can propagate to the piezo sensors. The piezo sensors can detect one or more changes in the mechanical properties (e.g., amount of pull, compression, twisting, etc.) of the piezo sensors and can generate one or more electrical signals indicative of the one or more changes in mechanical properties. The system can use the one or more electrical signals to determine the user&#39;s physiological information (e.g., heart rate, heart rate variability, respiratory rate, and respiratory rate variability). 
     In some examples, the piezo sensor can include planar layers.  FIG. 3  illustrates an exemplary piezo sensor including a piezo film according to examples of the disclosure. Piezo sensor  301  can be capable of being subject to mechanical forces. The monitoring system can be configured to apply an electrical poling field on the piezo film to sensitize the film to particular mechanical distortions (e.g., compression, bending, etc.). For example, a piezo film having a d33 mode can have an applied field strength and an applied force (or induced strain) both in the direction of the z-axis. The electrical signal can be indicative of the compression applied along the z-axis direction. Alternatively, a piezo film having a d31 mode can have an applied field strength in the direction of z-axis, along with an applied force (or induced strain) in the direction of the y-axis. The electrical signal can be indicative of the in-plane stretching along the y-axis. In some examples, piezo sensor  301  stackup can include a polymer film (e.g., PVDF or PLLA) and an insulator located between two electrodes, where the layers of the stackup can cover the entire surface of the piezo sensor  301  (e.g., piezo sensor  230  or piezo sensor  232 ). 
     Examples of the disclosure can include adjusting the dimension(s) of the piezo film to increase signal coupling. In some instances, the area (e.g., thickness, width, and/or length) of the piezo film can be increased, thereby increasing the coupling and/or response of the piezo film to the applied force. For example, the width of the piezo film can be increased (e.g., the width of piezo sensor  230  illustrated in  FIG. 2A  can be increased to 50% or greater than the width of mat  200 ). Due to the increased width, the piezo film can experience a higher amount of stretch in response to an applied force from the user&#39;s body. Increasing the area of the piezo film can also decrease inaccuracies and/or errors. For example, if the piezo sensor is not located directly under the user&#39;s heart, the heart rate and heart rate variability measurements may be inaccurate. Changing the dimensions of the piezo film can allow one or more piezo sensors to be located directly under certain body parts of the user. Moreover, the increased area can give the monitoring system the capability of selectively choosing which one or more piezo sensors to activate or include in the analysis, e.g., for enhanced signal-to-noise ratio (SNR) and/or signal quality. 
     In some instances, one or more dimensions of the piezo film can be decreased to lessen the degree of measuring movements unrelated to the desired measurements (e.g., heart rate, heart rate variability, pulse rate, and pulse rate variability). In some examples, one or more dimensions can be decreased to lessen the likelihood of measuring unwanted mechanical modalities (e.g., stretching, bending, etc.); alternatively, the one or more dimensions can be increased to capture a large number of mechanical modalities. 
     In some examples, the piezo sensor can include one or more corrugations.  FIG. 4A  illustrates a cross-sectional view of an exemplary piezo sensor including corrugations according to examples of the disclosure. Piezo sensor  401  can include a piezo film  411  having corrugations such as peaks  410  and valleys  412 . Other corrugations can include, but are not limited to, folds, creases, and bends. The corrugations can create localized regions with increased mechanical response (e.g., sensitivity) to force  420 . Piezo sensor  401  can further include a plurality of sections  414 ; each section can spatially separate adjacent corrugations (e.g., a section  414  can be located between a peak  410  and a valley  412 ). In some instances, peaks  410  (and/or valley  412 ) can be more sensitive to force  420  than sections  414 . Electrical response to, for example, force  420  can also dependent on the relative stiffness of the various layers including stiffness of the electrodes. The stiffness can also be designed to enhance or mitigate electrical response. 
     For a given peak  410  and/or valley  412 , force  420  can create a change in the angle of the corrugation with the corresponding induced piezoelectric signal, which can lead to a different response than force applied to a non-corrugated piezo film (e.g., piezo sensor  301 ). The changes in angles of some or all of the corrugations can be used to create a three-dimensional image of the movement of the user&#39;s body. In some examples, the piezo sensor  401  can include a piezo film  411  located between electrodes  413 . Piezo film  411  can undergo mechanical distortions or deformations (from force  420 ) and can generate one or more electrical signals indicative of the changes in mechanical properties. Electrodes  413  can propagate the electrical signal(s) to a controller for processing and analysis. In some examples, electrodes  413  can each be a single electrode configured to couple to multiple (e.g., all) corrugations. 
     In some examples, the electrodes located at the corrugations can be isolated electrodes sections, as illustrated in  FIG. 4B . Each electrode section  415  can be electrically isolated and independently operable from other electrode sections  415 . With electrode sections  415  located on the corrugations, the charge created by piezo film  411  (and measured by the corresponding electrode sections  415 ) can be due to mechanical forces located at the corrugations. In some instances, the charge at each corrugation can exclude mechanical forces detected at sections  414  (or any other regions less sensitive to mechanical force). The piezo film and electrodes located on the corrugations can enhance the sensitivity and resolution of piezo sensor  401 . Mechanical (e.g., stiffness, relative size, etc.) differences in the electrode sections, for example, in electrode section  415  can also be designed to enhance or mitigate electrical response by affecting the transformation of deformation stress from the applied forces into material strain. 
     In some examples, each electrode section  415  can be routed using a trace  417 . Each trace  417  can be disposed, but electrically isolated from (e.g., by including an insulator  418  adjacent to trace  417 ) one or more of the other electrode sections  415 . For example, each pair of electrode sections can be electrically coupled to a corrugation separate from other pairs of electrode sections. An insulator  418  can be located between at least one electrode section corresponding to a first pair and another electrode section corresponding to a second pair. Alternatively or additionally, the traces can be routed around the other electrode sections  415 , but on the same layer, for example. Although  FIG. 4B  illustrates one trace  417 , one skilled in the art would understand that other traces  417  can be included and coupled to other electrode sections; one trace  417  is illustrated for clarity purposes. Electrical response to, for example, force  420  can also depend on the relative mechanical (e.g., stiffness) properties of the various traces, where the mechanical properties of the traces can be designed to enhance or mitigate electrical response. 
     In some examples, a voltage can be generated across each electrode section  415 , and electrical signals from the electrode sections  415  can be aggregated (e.g., added together) and/or amplified. In some instances, the same force  420  can cause mechanical deformations of peaks  410  to be different from the mechanical deformations of valleys  412 . As a result, the electrical signals from the peaks  410  can cancel (or reduce) the electrical signals from the valleys  412  if the electrical signals are merely added together. 
     To avoid cancellation (or unwanted reduction) of the electrical signals, the electrode sections  415  associated with peaks  410  can be subsampled with one polarity (or phase), and electrode sections  415  associated with valleys  412  can be subsampled with an opposite polarity (or phase).  FIG. 4C  illustrates an exemplary method for operating a corrugated piezo sensor including electrically isolated electrode sections according to examples of the disclosure. An external force can be applied to the mat (step  452  of process  450 ). The external force can cause mechanical distortions or deformations to the corrugations of the piezo sensor (step  454  of process  450 ). First electrical signals from electrode sections coupled to each peak of the corrugated piezo sensor can be measured (step  456  of process  450 ). Second electrical signals from electrode sections coupled to each valley can be measured (step  458  of process  450 ). In some examples, valleys can be measured before peaks are measured. In some examples, some peaks can be measured, followed by some valleys being measured, followed by some peaks being measured, etc. A controller can aggregate the electrical signals (step  460  of process  450 ) (e.g., the electrical signals can have different polarities or phases depending on the structure of the corrugation), which can lead to an enhanced overall electrical signal. 
     An alternative for avoiding or reducing cancellation of the electrical signals of the electrode sections can be to electrically couple some of the electrode sections together, as illustrated in  FIG. 4D . For example, trace  419  can couple an electrode section  415  to a peak  410  and can couple an electrode section  415  to a valley  412 . In some examples, one or more vias  416  can be used to route trace  419  from the one electrode section  415  located on one layer through the piezo film  411  to another electrode section  415  located on another layer. In some examples, one or more insulators (not shown) can be included to allow traces  417  and/or electrode sections  415  to cross over without electrically coupling. 
     Examples of the disclosure can include piezo sensors including multiple layers, such as illustrated in  FIG. 5A . Stackup  503  can include electrode  517 , electrode  519 , and electrode  521  interleaved with piezo film  511  and piezo film  513 . Electrode  517 , electrode  519 , and electrode  521  can each be single electrodes having the same area as the piezo films. In some examples, electrode  517  and electrode  519  can electrically couple to piezo film  511 . In some examples, electrodes  519  and electrode  521  can electrically couple to piezo film  513 . Examples of the disclosure can include corrugations (not shown). Electrical response to the applied force can also depend on the relative mechanical (e.g., stiffness) properties of the various traces, where the mechanical properties of the traces can be designed to enhance or mitigate electrical response. 
     In some examples, one or more electrodes can include electrode sections. For example, as illustrated in  FIG. 5B , stackup  505  can include a single electrode  519  (e.g., having the same area as piezo film  511  and piezo film  513 ) that can be located in both peak(s)  510  and valley(s)  512 . Stackup  505  can further include electrode sections  515 , where each corrugation can include an electrode section  515 . For example, at peak  510 , electrode section  515  and electrode  519  can electrically couple to piezo film  511 . At valley  512 , electrode section  515  and electrode  519  can electrically couple to piezo film  513 . Electrical response to the applied forces on the electrode sections can also depend on the relative mechanical (e.g., stiffness) properties of the electrode sections, where the mechanical properties of the traces can be designed to enhance or mitigate electrical response. 
     In some examples, electrode sections  515  can be located on the same side (e.g., outer side) of the corrugation (not shown). For example, at peak  510 , an electrode section  515  can be located on the top of peak  510 . At valley  512 , an electrode section  515  can be located on the bottom of valley  512 . In some examples, each corrugation can include multiple (e.g., two) electrode sections  515 . For example, each corrugation can include an electrode section located on the top and an electrode section located on the bottom of the corrugation, in addition to electrode  519 . The piezo electric sensor can be configured with multiple electrodes, thereby increasing the number of electrical signals. The electrical signals can be associated with different orthogonal layers to create a matrix of information, for example, associated with the user. 
     Although the non-corrugated sections (located between corrugations) may have lower mechanical response (e.g., sensitivity to mechanical force) compared to the corrugations, the non-corrugated sections can still measure mechanical force, albeit possibly a different type and/or magnitude of mechanical force. In some examples, an electrode section  523  can be located at the non-corrugated sections in between corrugations, as illustrated in  FIG. 5C . In some examples, electrode sections  515  and electrode sections  523  can each be individually routed and independently operable. In some examples, two or more electrode sections  515  can be electrically coupled together, and/or two or more electrode sections  523  can be electrically coupled together. Although  FIG. 5C  illustrates electrode sections  523  located on both sides of the stackup  507 , examples of the disclosure can include an electrode section located on one side (e.g., on top) of stackup  507 , without being limited to the same side for each non-corrugated section. 
     Examples of the disclosure can further include piezo sensors having multiple piezo film elements, where the force (e.g., stress) can be concentrated onto the piezo film elements.  FIG. 6A  illustrates an exemplary piezo sensor including multiple piezo film elements according to examples of the disclosure. Piezo sensor  601  can include piezo film elements  612 , where each piezo film element  612  can be structurally and electrically isolated from the other piezo film elements  612 . In some examples, piezo film elements  612  can be coupled to electrodes (not shown), which can generate independent electrical signals and/or can be independently operable. The piezo film elements  612  can include one or more intermediate layers, such as layer  614 , configured to transfer force  620  to the piezo film elements  612 . That is, layer  614  can concentrate compressive (i.e., transverse) forces at the external surface of the piezo sensor (e.g., interface of the mat (or the bed) and user&#39;s body) to piezo film elements  612 . In some examples, layer  614  can be tapered, thereby allowing force  620  applied across the top of the piezo sensor  601  to concentrate at piezo film elements  612  (e.g., force applied across a larger region can be concentrated to multiple, smaller regions). Layer  614  can be configured with a larger volume of material located closer to the external surface of the piezo sensor  601  (e.g., the surface directly contacting the mat, bed, and/or user) than the piezo film elements  612 . Piezo film elements  612  can include one or more functions and/or structure (e.g., corrugations), as discussed above. Although  FIG. 6A  illustrates two layers  614  surrounding piezo film elements  612 , examples of the disclosure can include any number of layers  614 , such as one layer  614 . Examples of the disclosure further include electrodes and routing traces coupled to the piezo film elements  612 , although not illustrated in the figure. The electrodes and routing traces can have one or more functions and/or structures as electrodes and routing traces described previously. 
     In some examples, as illustrated in  FIG. 6B , piezo sensor  601  can include one or more structures  616  located between layer  614  and piezo film elements  612  to enhance the transfer of mechanical force  620  to the piezo film elements  612 . By concentrating the force, the monitoring system can better capture mechanical deformations (e.g., local bending). Although  FIG. 6B  illustrates one or more structures  616  located on one side of piezo film elements  612 , examples of the disclosure can include one or more structures located on multiple sides of piezo film elements  612 . 
     Although the figures illustrate piezo film elements  612  as discrete elements, examples of the disclosure can include piezo film elements  612  structurally connected by a film layer, as illustrated in  FIG. 6C . Each piezo film element  612  can be physically separated from other piezo film elements  612  by film sections  619 . In some examples, the film sections can be responsive to mechanical forces applied to the film layer  613 . The mechanical force experienced by the film sections  619  can propagate to one or more piezo film elements  612 . In some instances, forces applied to discrete piezo film elements  612  not connected through a film layer can cause the discrete piezo film elements to move, but such movement may not be sensed by the monitoring system. Film layer  613  can help prevent any missed movements. In some examples, films sections  619  can have a different force concentration (e.g., mechanical strength, rigidity, and/or material density) than piezo film elements  612 . In such a manner, film sections  619  can experience a different amount (e.g., less) of force  620  than piezo film elements  612 . In some instances, film sections  619  can be less sensitive to force than piezo film elements  612 . 
     In some examples, force concentration can be implemented by configuring the intermediate layer(s) to have regions of different force concentration (e.g., mechanical strength, rigidity and/or density).  FIG. 6D  illustrates an exemplary piezo sensor including an intermediate layer having regions of differing force concentration according to examples of the disclosure. Layer  618  can include multiple (e.g., two) regions such as region  615  and region  617  having different structural properties. For example, region  617  can include a higher density material than region  615 . Layer  618  can be configured to transfer mechanical force  620  to the piezo film elements  612 . The difference in density in region  617  relative to region  615  can cause region  617  to concentrate a greater amount of force from force  620  than region  615 , and electrodes coupled to the piezo film elements  612  can generate electrical signals indicative of the force. In some examples, the dimensions (e.g., thickness) of the region  615  and region  617  can be the same. 
     Force concentration can also be implemented using a corrugated piezo film and one or more structures, as illustrated in  FIG. 6E . Piezo sensor  607  can include a piezo film  611  having corrugations such as peaks  610  and valleys  612 . Other corrugations can include, but are not limited to, folds, creases, and bends. The corrugations can create localized regions with increased sensitivity to mechanical force. Piezo sensor  607  can also include a plurality of non-corrugated sections  614 , each non-corrugated section  614  spatially separating adjacent corrugations (e.g., a section  614  can be located between a peak  610  and a valley  612 ). 
     Piezo sensor  607  can further include one or more structures  616  located between the interface  606  (e.g., an external surface of piezo sensor  607 ) and piezo film  611 . In some examples, interface  606  can include a planar layer(s) of material. For a given corrugation (e.g., peak  610  or valley  612 ), structures  616  can transfer force applied to interface  606  to piezo film  611 , creating a change in the angle of the corrugation; which can lead to a different response than force applied to a non-corrugated piezo film (e.g., piezo sensor  301  illustrated in  FIG. 3 ). The changes in angles of some or all of the corrugations can be used to create a three-dimensional image of the movement of the user&#39;s body. In some examples, the stackup of piezo sensor  607  can include electrodes (not shown) and routing traces (not shown) electrically coupled to piezo film  611  to measure and route the electrical signals from piezo film  611  to a controller. The electrodes and routing traces can have one or more functions and/or properties of electrodes and routing traces as discussed above. 
       FIG. 6F  illustrates an exemplary method for operating a piezo sensor including a plurality of piezo film elements according to examples of the disclosure. An external force (e.g., force  620  illustrated in  FIGS. 6A-6D ) can be applied to the mat (step  652  of process  650 ). One or more layers (e.g., layer  614  illustrated in  FIGS. 6A-6C , layer  618  illustrated in  FIG. 6D , or a layer located at interface  606  of  FIG. 6E ) can transfer the external force to one or more piezo film elements (e.g., piezo film elements  612  illustrated in  FIG. 6A-6D  or piezo film  611  illustrated in  FIG. 6E ) or one or more structures (e.g., structures  616  illustrated in  FIGS. 6B and 6E ) (step  654  of process  650 ). Optionally, when applicable, the one or more structures can transfer the transferred force to one or more piezo film elements (step  656  of process  650 ). Electrical signal(s) from electrode sections coupled to each piezo film element can be measured (step  658  of process  650 ). A controller can receive, and optionally, process the electrical signal(s) (step  660  of process  650 ). 
     Examples of the disclosure can further include piezo sensors configured for converting one type of force into another type of force by Poisson conversion.  FIG. 7  illustrates an exemplary piezo sensor configured to convert forces by Poisson conversion according to examples of the disclosure. Piezo sensor  701  can include material  741  and material  743 , where each material can convert an applied force into another type of force. That is, the piezo sensor  701  can convert the applied force  720  into a different mechanical mode. For example, the user&#39;s body can create a compressive force (i.e., transverse force) at the external surface of the piezo sensor  701  (e.g., interface of the mat and the user&#39;s body). Material  741  and material  743  can be, for example, a material with a high Poisson ratio. A material with a high Poisson ratio includes, but is not limited to, rubber. Material  741  and material  743  can experience the compressive force and can convert the compressive force into a lateral strain (i.e., longitudinal force). That is, compression of material  741 , material  743 , or both along one axis (e.g., z-axis) can result in expansion of the respective material along another axis (e.g., x-axis). Piezo sensor  701  can further include piezo film  719 , which can be bonded to and located between material  741  and material  743 . The lateral strain from material  741 , material  743 , or both can be transferred to piezo film  719 , enhancing the d31 response (rather than a d33 response). 
     By including multiple elements in the piezo sensors, the monitoring system can analyze physiological information based on multiple mechanical modalities. For example, instead of measuring mere compressive forces due to the user&#39;s body weight, the piezo sensors can be capable of measuring both compressive and stretching forces. Furthermore, the monitoring system can include different types of piezo sensors and/or piezo sensors of the same type, but configured for multiple modalities. Referring back to  FIG. 2B , for example, some piezo sensors  234  can be configured as a first type of piezo sensor (e.g., corrugated piezo sensors such as piezo sensor  401  illustrated in  FIG. 4A ) and other piezo sensors  234  can be configured as a second type of piezo sensor (e.g., force concentration piezo sensors such as piezo sensor  601  illustrated in  FIG. 6A ). As another example, some piezo sensors can be configured for a first mechanical modality (e.g., compression) and other piezo sensors can be configured for a second mechanical modality (e.g., bending). In some examples, the first type of piezo sensors and the second type of piezo sensors can be interleaved along the mat. Additionally or alternatively, the rows and/or columns of piezo sensors can be staggered. Examples of the disclosure can include the piezo sensors arranged in any configuration including, but not limited to, a configuration of rows and columns. 
     As discussed above, examples of the disclosure can include measuring a plurality of vital signs for one or more users. Additional information can be used to improve the delivery of measured information, analysis, or any other content that may be of interest to the users. In some examples, the measured information, analysis, or other content may include personal information that may uniquely identify the user or may be used to contact or locate the user. Such personal information can include geographic information, demographic information, telephone numbers, email addresses, mailing addresses, home addresses, or other identifying information. In some examples, the use of such personal information can be used to the benefit of the user. For example, the personal information can be used to deliver to the user the measured information, analysis, or other content. Use of personal information can include, but is not limited to, enabling timely and controlled delivery of the content. 
     The disclosure also contemplates that an entity that may be using (e.g., measuring, collecting, analyzing, disclosing, transferring, and/or storing) the personal information will comply with well-established privacy policies and/or privacy practices. These privacy policies and/or privacy practices can be generally recognized as meeting (or exceeding) industry or governmental requirements for private and secure personal information and should be implemented and consistently used. For example, personal information should be collected for legitimate and reasonable purposes and should not be shared (e.g., sold) outside of those purposes. Furthermore, collected personal information should occur only after receiving the informed consent of the user(s). To adhere to privacy policies and/or privacy practices, entities would take any steps necessary for safeguarding and securing outside access to the personal information. In some examples, entities can subject themselves to third party evaluation(s) to certify that the entities are adhering to the well-established, generally recognized privacy policies and/or privacy practices. 
     In some examples, the user(s) can selectively block or restrict access to and/or use of the personal information. The monitoring system can include one or more hardware components and/or one or more software applications to allow the user(s) to selectively block or restrict access to and/or use of the personal information. For example, the monitoring system can be configured to allow users to “opt in” or “opt out” of advertisement delivery services when collecting personal information during registration. In some examples, a user can select which information (e.g., home address) to withhold from the advertisement delivery services. 
     Although examples of the disclosure can include monitoring systems and methods for measuring vital signs with the use of the user&#39;s personal information, examples of the disclosure can also be capable of one or more functionalities and operation without the user&#39;s personal information. Lack of all or a portion of the personal information may not render the monitor systems and methods inoperable. In some examples, content can be selected and/or delivered to the user based on non-user specific personal (e.g., publicly available) information. 
     A multi-element piezo sensor is disclosed. In some examples, the multi-element piezo sensor comprises: a piezo film including a plurality of corrugations, each corrugation separated from another corrugation by a section, wherein each corrugation has a higher mechanical response to an external force than surrounding sections, the one or more corrugations configured to change an angle in response to the external force; a plurality of electrodes configured to electrically couple to the piezo film; and a plurality of routing traces configured to route one or more electrical signals from the plurality of electrodes to a controller. Additionally or alternatively, in some examples, at least one of the plurality of electrodes is a single electrode configured to electrically couple to multiple corrugations. Additionally or alternatively, in some examples, the plurality of electrodes are configured as a plurality of electrode sections, each pair of electrode sections electrically coupled to a corrugation separate from other pairs of electrode sections, each pair of electrode sections electrically isolated from other pairs of electrode sections. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a plurality of insulators, each insulator configured to electrically insulate pairs of electrode sections and located between at least two electrode sections corresponding to different pairs of electrode sections. Additionally or alternatively, in some examples, the piezo film includes at least one via, the plurality of corrugations includes at least one peak and at least one valley, and at least one routing trace electrically couples the at least one peak to the at least one valley and is routed through the at least one via. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a second piezo film; and a second electrode configured to electrically couple to the second piezo film, wherein at least one of the plurality of electrodes is further configured to electrically couple to the second piezo film. Additionally or alternatively, in some examples, the plurality of corrugations of the piezo film includes at least one peak and at least one valley, the multi-element piezo sensor further comprising: a second piezo film including a second plurality of corrugations, the second plurality of corrugations including: at least one peak corresponding to the at least one peak of the piezo film, and at least one valley corresponding to the at least one valley of the piezo film; and a second plurality of electrodes, wherein some of the second plurality of electrodes electrically couple to the piezo film, and others of the second plurality of electrodes electrically couple to the second piezo film. Additionally or alternatively, in some examples, the some of the second plurality of electrodes are located on a side of the piezo film, and the others of the second plurality of electrodes are located on an opposite side of the piezo film. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a plurality of electrode sections, each electrode section located between adjacent corrugations. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a plurality of structures configured to transfer force from an external surface of the multi-element piezo sensor to the plurality of corrugations, each structure located between the external surface and one of the plurality of corrugations. 
     A multi-element piezo sensor is disclosed. In some examples, the multi-element piezo sensor comprises: a plurality of piezo film elements, each piezo film element electrically isolated from the other piezo film elements; one or more layers, each layer configured to transfer force from an external surface of the multi-element piezo sensor to the plurality of piezo film elements; a plurality of electrodes configured to electrically couple to the plurality of piezo film elements; and a plurality of routing traces configured to route one or more electrical signals from the plurality of electrodes to a controller. Additionally or alternatively, in some examples, each layer includes a plurality of tapers, each taper having a larger volume of material closer to the external surface than the plurality of piezo film elements. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a plurality of structures configured to transfer force from the one or more layers to the plurality of piezo film elements, each structure located between one of the plurality of piezo film elements and the one or more layers. Additionally or alternatively, in some examples, the multi-element piezo sensor further comprises: a film layer including the plurality of piezo film elements and a plurality of film sections, each film section separating adjacent piezo film elements. Additionally or alternatively, in some examples, each film section has one or more different mechanical properties than each piezo film element. Additionally or alternatively, in some examples, each layer includes one or more first regions and one or more second regions, the one or more second regions configured to transfer a greater amount of force than the one or more first regions. 
     A multi-element piezo sensor is disclosed. In some examples, the multi-element piezo sensor comprises: two or more layers configured to respond to a first force modality applied to an external surface of the multi-element piezo sensor, the response including a Poisson conversion to a second force modality, different from the first force modality; one or more piezo films located between at least two of the two or more layers; a plurality of electrodes configured to electrically couple to the one or more piezo films; and a plurality of routing traces configured to route one or more electrical signals from the plurality of electrodes to a controller. Additionally or alternatively, in some examples, the first force modality is a compressive force, and the second force modality is a stretching force, and the one or more electrical signals includes information indicative of the stretching force. 
     A method for detecting an external force comprising: changing one or more mechanical properties of one or more corrugations of a piezo film in response to the external force; electrically coupling to the one or more corrugations of the piezo film; generating one or more electrical signals indicative of the change in the one or more mechanical properties; measuring the one or more electrical signals; and determining physiological information based on the measured one or more electrical signals. Additionally or alternatively, in some examples, measuring the one or more electrical signals includes: associating one or more first electrical signals with peaks of the one or more corrugations; measuring the one or more first electrical signals; associating one or more second electrical signals with valleys of the one or more corrugations; measuring the one or more second electrical signals; and aggregating the one or more first and the one or more second electrical signals. 
     Although examples have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the various examples as defined by the appended claims.

Metadata:
Filing Date: 20180522
Publication Date: 20220531
Grant Date: 20220531
Priority Date: 20170522
Inventors: HAN, Chin San
ALVAREZ, GERMAN A.
QUIJANO, SANTIAGO
WENZEL, STUART W.
Assignee: APPLE INC
CPC Classifications: [{"code": "A61B5/6892", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B2562/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01L1/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/0205", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6802", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01L1/205", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L1/205", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6802", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01L1/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/1126", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2560/0462", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/742", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2560/0252", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0462", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/4806", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/0205", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/1126", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/742", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0252", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/4806", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L41/0838", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L41/1132", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B2562/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L41/0805", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01L1/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/1126", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6802", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0252", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01L1/205", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/742", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2560/0462", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L41/047", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/0205", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10N30/302", "inventive": true, "first": true, "tree": "[]"}, {"code": "H10N30/508", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10N30/87", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10N30/704", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 62599701