Wearable device antenna

A wearable device includes a frame and a magnetic coupler opening formed in the frame. Wearable device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. Wearable device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb received VHF band radio modulated signals from the tissue of the user.

TECHNICAL FIELD

The present subject matter relates to wearable devices, e.g., eyewear devices, and mobile devices, with magnetic couplers to utilize the human body as a very high frequency (VHF) conduit or antenna.

BACKGROUND

Wearable devices, including portable eyewear devices, such as smartglasses, headwear, and headgear, as well as mobile devices available today integrate radio frequency (RF) transceivers that operate around 2.4 GHz, which is in the ultra-high frequency (UHF) range. WiFi and Bluetooth® are examples of networking protocols that operate around 2.4 GHz in the UHF band. At the 2.4 GHz band, radio waves propagate mainly by line of sight, but are blocked by hills and large buildings; however, the transmission through building walls is strong enough for indoor reception.

Very high frequency (VHF) band is a designation used for the range of radio frequency (RF) electromagnetic waves from 30 to 300 megahertz (MHz). Many well-known, popular wireless technologies occupy this part of the radio spectrum, including frequency modulation (FM) radio, digital television (DTV), and car remotes. Older FM radio technologies have found their way into some modern mobile consumer electronics and are very popular in some parts of the world. Propagation of VHF waves through the air is very good, as is the ability of VHF waves to pass through many non-metallic substances.

Unfortunately, antenna design for the VHF radios inside modern smart mobile devices and wearable devices have been a challenge since the wavelengths are so large, ranging from 10 meters to a meter. The ideal half wavelength dipole antenna cannot possibly fit inside a mobile device anyone wants to carry with them daily or a wearable device. Antenna engineers in the mobile device space have attempted to address this problem by using earphone cables as an antenna because earphone cables can provide a long electrical length needed to operate in the VHF band. However, VHF antenna headphones are not a solution for wearable devices or even for mobile devices in situations where the user does not listen to audio and desires to exchange general data (non-audio data).

Accordingly, size limitations and the small form factor of wearable devices can make VHF antennas difficult to incorporate into the devices. The space for placement of the VHF antenna on the wearable device is limited. A need exists to integrate VHF antenna capabilities with wearable devices, including eyewear devices, and mobile devices for general data exchange, such as non-audio purposes.

DETAILED DESCRIPTION

The term “coupled” or “connected” as used herein refers to any logical, optical, physical or electrical connection, link or the like by which electrical or magnetic signals produced or supplied by one system element are imparted to another coupled or connected element. Unless described otherwise, coupled or connected elements or devices are not necessarily directly connected to one another and may be separated by intermediate components, elements or communication media that may modify, manipulate or carry the electrical signals. The term “on” means directly supported by an element or indirectly supported by the element through another element integrated into or supported by the element.

The orientations of the eyewear device, associated components and any complete devices incorporating a magnetic coupler such as shown in any of the drawings, are given by way of example only, for illustration and discussion purposes. In operation for exchanging data via the magnetic coupler, the eyewear device may be oriented in any other direction suitable to the particular application of the eyewear device, for example up, down, sideways, or any other orientation. Also, to the extent used herein, any directional term, such as front, rear, inwards, outwards, towards, left, right, lateral, longitudinal, up, down, upper, lower, top, bottom and side, are used by way of example only, and are not limiting as to direction or orientation of any magnetic coupler or component of a magnetic coupler constructed as otherwise described herein.

In a first example, an eyewear device includes a frame that has a bridge and a temple connected to a lateral side of the frame. Eyewear device further includes a magnetic coupler opening formed in the temple or the bridge. Eyewear device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. VHF radio transceiver includes a transmitter to modulate a VHF band radio carrier signal with data to generate transmitted VHF band radio modulated signals during transmission. VHF radio transceiver further includes a receiver to demodulate received VHF band radio modulated signals into data during reception. Eyewear device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate the transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb the received VHF band radio modulated signals from the tissue of the user. Eyewear device further includes a memory accessible to the processor and programming in the memory.

Execution of the programming by the processor configures the eyewear device to perform functions, including functions to modulate, via the VHF radio transceiver, the VHF band radio carrier signal with data to generate the transmitted VHF band radio modulated signals during transmission. The execution of the programming by the processor further configures the eyewear device to, during transmission, radiate, via the magnetic coupler, the transmitted VHF band radio modulated signals into the tissue of the user. The execution of the programming by the processor further configures the eyewear device to, during reception, absorb, via the magnetic coupler, the received VHF band radio modulated signals from the tissue of the user. The execution of the programming by the processor further configures the eyewear device to demodulate, via the VHF radio transceiver, the received VHF band radio modulated signals into data during reception.

In a second example, a wearable device includes a frame and a magnetic coupler opening formed in the frame. Wearable device further includes a processor, a memory accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. VHF radio transceiver includes a transmitter to modulate a VHF band radio carrier signal with data to generate transmitted VHF band radio modulated signals during transmission. VHF radio transceiver further includes a receiver to demodulate received VHF band radio modulated signals into data during reception. Wearable device further includes a magnetic coupler connected to the VHF radio transceiver. Magnetic coupler includes a diamagnetic material shaped to form a VHF transmission or reception terminal that partially or fully aligns with the magnetic coupler opening. During transmission, magnetic coupler is configured to radiate the transmitted VHF band radio modulated signals into tissue of the user. During reception, magnetic coupler is configured to absorb the received VHF band radio modulated signals from the tissue of the user. Wearable device further includes a memory accessible to the processor and programming in the memory.

Execution of the programming by the processor configures the wearable device to perform functions, including functions to modulate, via the VHF radio transceiver, the VHF band radio carrier signal with data to generate the transmitted VHF band radio modulated signals during transmission. The execution of the programming by the processor further configures the wearable device to, during transmission, radiate, via the magnetic coupler, the transmitted VHF band radio modulated signals into the tissue of the user. The execution of the programming by the processor further configures the wearable device to, during reception, absorb, via the magnetic coupler, the received VHF band radio modulated signals from the tissue of the user. The execution of the programming by the processor further configures the wearable device to demodulate, via the VHF radio transceiver, the received VHF band radio modulated signals into data during reception

FIG. 1Ais a side view of an example hardware configuration of an eyewear device100, which includes at least one magnetic coupler120on a right temple125B to utilize a human body as a conduit or antenna for radio frequency (RF) signals for data transmission and reception. While described in terms of an eyewear device100in the example, it should be understood that the magnetic coupler120and other components described herein can be incorporated into other wearable devices or a mobile device, as described in further detail below. The wearable device can be a bracelet, watch, wristband, or other portable device designed to be worn by a user to communicate via one or more wireless networks or wireless links with other wearable devices, mobile device (element690ofFIG. 6), or server system (element698ofFIG. 6).

When the magnetic coupler120described herein is utilized, efficient coupling with the human body can be obtained which allows the human body act as a conduit or antenna for transmission and reception of the VHF band radio signals. As used herein, the human body is the entire structure of a human being and includes different types of cells that together create tissues and organ systems. The human body includes a head, neck, trunk (e.g. thorax and abdomen), arms, hands, legs, and feet.

Given the height of an average human and the electrical properties of the body, incident VHF band radio signals on human tissue can generate somewhat meaningful signals when a human touches the RF front end of a VHF radio. For example, when two humans make skin-to-skin contact (e.g., handshake or fist bump) VHF radio waves can be transmitted between the two human bodies. While the human body is not a good conductor compared to a half wavelength dipole antenna, meaning the efficiency in received VHF signals are relatively low, human tissue does not actually need to be very highly efficient to work in the VHF band compared to the UHF band. The key, then, to use the human body as a conduit or antenna in the VHF band is to be able to extract RF energy as efficiently as possible via the magnetic coupler120and feed that signal to the RF front end for optimum radio performance, which the magnetic coupler120described herein enables.

In the example ofFIG. 1A, the magnetic coupler120is sensitive to the VHF band, which can be low power transmission (e.g., less than 1 milliwatt) of RF signals in the FM band, which range from approximately 87.5 MHz to 108.0 MHz, in 200 kHz steps. As shown in the example, the magnetic coupler120is inwards facing from the perspective of a wearer of the eyewear device100. Generally, received VHF radio signals are captured by the magnetic coupler120, fed to a VHF radio transceiver (element241ofFIG. 2B). If an envelope detector (element242ofFIG. 2B) determines the received VHF radio signals exceed a threshold, those radio signals are digitized by a processor (element243ofFIG. 2B), and stored in a memory (element634ofFIG. 6). As will be described in further detail below, envelope detector (element242ofFIG. 2B), detects an amplitude of VHF waves to determine whether two users are intending to send VHF waves to each other or if the VH waves are just background noise. For example, if the amplitude or VHF radio signal strength is high, envelope detector (element242ofFIG. 2B) determines the two users are first bumping and thus intending to exchange user identifiers with each other. If the amplitude or VHF radio signal strength is low, envelope detector (element242ofFIG. 2B) discards the VHF radio signals as background noise, as is the case when the two users are sitting next to each other on a bus, but not making skin-to-skin contact. Envelope detector (element242ofFIG. 2A) seeks to detect only those VHF radio signals intended for the user by using comparison radio signal strength indicator thresholds.

Transmission of VHF radio signals work similar to reception mode, but in reverse. For example, the electromagnetic fields pass through the magnetic coupler120in reverse, which creates a current in a driven element (see310ofFIG. 3) and that current goes to the VHF radio transceiver (element241ofFIG. 2B) where the current is demodulated. VHF radio transceiver (element241ofFIG. 2B) includes a radio mounted on a flexible PCB (element240ofFIG. 2B). An RF signal (element230ofFIG. 2B), which can be an RF input/output stream, is supplied or received to/from a driven element (element310ofFIG. 3) by the VHF radio transceiver (element241ofFIG. 2B). For example, an RF output (element225ofFIG. 2B) includes two wires connected from VHF radio transceiver (element241ofFIG. 2B) to the driven element (element310ofFIG. 3). Driven element (element310ofFIG. 3) wraps around diamagnetic material (element305ofFIG. 3), e.g., with low loss and high magnetic permeability), which couples to the tissue of the user (element360ofFIG. 3). In one example of reception mode, there is broadcasting of a user identifier modulated in electromagnetic fields, which are transferred through a sender human body. When the electromagnetic fields are coupled to a receiver human body, the electromagnetic fields go through the magnetic coupler120in reverse. This creates current on the driven element (element310ofFIG. 3) and the current goes to a receiver circuit of the VHF radio transceiver (element241ofFIG. 2A). The receiver circuit demodulates information corresponding to the user identifier.

In both reception and transmission modes, the structure and orientation of the magnetic coupler120maximizes efficiency. VHF radio transceiver (element241ofFIG. 2B) transmits or receives small packets of information, such as user identifiers, at low power levels and in short periods. In some of the examples herein, the magnetic coupler120is coupled to human skin and includes a U-shaped or half toroid piece of ferrite with an electrically conductive coil wrapped around. As explained in further detail below, ferrite is a type of magnetic permeable material, which is nonconductive. Generally, the magnetic coupler120is formed of a diamagnetic material (element305ofFIG. 3), which typically have a relative magnetic permeability higher than one (μ≈12.57×10−7H/m). A magnetic coupler120formed of a low relative permeability material may be insufficient to provide highly efficient magnetic coupling. Hence, in some examples, the magnetic permeability of the diamagnetic material (element305ofFIG. 3) is highly permeable, meaning materials with a permeability of approximately 10 to or greater; thus, the VHF magnetic energy is increased by ten-fold for the same amount of current inside the diamagnetic material305.

VHF band radio signals from a VHF radio transceiver (element241ofFIG. 2B) are efficiently coupled to the human body in order to reduce the operating power needs of the VHF radio transceiver (element241ofFIG. 2B). In an example, when two users, each of which is wearing a respective eyewear device100engage in skin-to-skin contact gestures (e.g., a fist bump or handshake), the RF energy is transferred between from one human body to the other human body with very low power (e.g., less than Bluetooth® protocol)

In an example, a system includes the eyewear device100. The eyewear device100includes a frame105, a right temple125B extending from a right lateral side170B of the frame105. For example, the right temple125B is connected to the right lateral side170B of frame105via right chunk110B. Eyewear device100may further include an image display (e.g., optical assembly180A-B shown inFIGS. 1B-C) to present a graphical user interface to a user. The eyewear device100can further include a camera (e.g., visible light camera314ofFIG. 3) connected to the frame105or the right temple125B to capture an image of a scene. Although not shown inFIGS. 1A-C, the eyewear device100further includes a processor (element243ofFIG. 2B) coupled to the eyewear device100and connected to the camera (element314ofFIG. 3). Eyewear device100further includes a memory (element634ofFIG. 6) accessible to the processor (element243ofFIG. 2B) and programming in the memory (element634ofFIG. 6), for example in the eyewear device100itself or another part of the system.

Eyewear device100includes a magnetic coupler opening115formed in the right temple125B or the bridge (element106ofFIG. 1B). The right temple125B is adapted to extend over an ear of a user. Although not shown inFIG. 1A, eyewear device100further includes a very high frequency (VHF) radio transceiver (element241ofFIG. 2B) for data transmission and reception and connected to the processor (element243ofFIG. 2B). VHF radio transceiver (element241ofFIG. 2B) includes a transmitter to modulate a VHF band radio carrier signal with data to generate transmitted VHF band radio modulated signals during transmission. VHF radio transceiver (element241ofFIG. 2B) further includes a receiver to demodulate received VHF band radio modulated signals into data during reception.

Magnetic coupler120is connected to the VHF radio transceiver (element241ofFIG. 2B) and includes a diamagnetic material (element305ofFIG. 3) shaped to form a RF transmission or reception terminal (element560ofFIGS. 5A-C) that partially or fully aligns with the magnetic coupler opening115. During transmission, magnetic coupler120is configured to radiate the transmitted VHF band radio modulated signals into tissue of the user (element360ofFIG. 3). During reception, magnetic coupler120is configured to absorb the received VHF band radio modulated signals from the tissue of the user (element360ofFIG. 3).

Electronics for the VHF radio transceiver (element241ofFIG. 2B) can be on a long flexible PCB240in the right temple125B as shown inFIG. 2B. Right chunk110B can also include other network transceivers, such as WiFi and Bluetooth®, as well as a visible light camera (element314ofFIG. 3) on another flexible PCB. In another example, RF output (element225ofFIG. 2B) can include two twisting wires from the flexible PCB in the right chunk110B that enter and run through the temple125B which then connect to the driven element (element310ofFIG. 3). Driven element (element310ofFIG. 3) can integrate the two wires of RF output (element225ofFIG. 2B), such that the VHF radio transceiver (element241ofFIG. 2B) is integrated with the driven element (element310ofFIG. 3). Alternatively, driven element (element310ofFIG. 3) can be a separate conductive medium that is integrated with the diamagnetic material (element305ofFIG. 3) of magnetic coupler120.

Execution of the programming by the processor (element243ofFIG. 2B) configures the eyewear device100to perform functions, including functions to modulate, via the VHF radio transceiver (element241ofFIG. 2B), the VHF band radio carrier signal with data to generate the transmitted VHF band radio modulated signals during transmission. The data (e.g., information signal) used to modulate the carrier VHF band carrier signal, alters some aspect and thus piggybacks on the VHF band carrier signal. The modulated VHF band carrier signal is amplified and applied to the transmitting magnetic coupler120. The oscillating current pushes the electrons in the transmitting magnetic coupler120back and forth, creating oscillating electric and magnetic fields, which radiate the energy away from the magnetic coupler120at the RF transmission or reception terminal (element560ofFIGS. 5A-C) creating VHF radio waves. The VHF radio waves carry the data (e.g., user identifier) from a wearer of the eyewear device100(transmitting human body) to a receiving human body that wears a receiving eyewear device with a receiving magnetic coupler.

The execution of the programming by the processor (element243ofFIG. 2B) further configures the eyewear device100to, during transmission, radiate, via the magnetic coupler120, the transmitted VHF band radio modulated signals into the tissue of the user (element360ofFIG. 3). The execution of the programming by the processor (element243ofFIG. 2B) further configures the eyewear device100to, during reception, absorb, via the magnetic coupler120, the received VHF band radio modulated signals from the tissue of the user (element360ofFIG. 3). At the receiving human body, the oscillating electric and magnetic fields of the incoming VHF radio wave push electrons back and forth to create a tiny oscillating voltage in the receiving magnetic coupler120, which is a weaker replica of the current from the transmitting magnetic coupler120. This voltage is applied to the VHF radio transceiver (element241ofFIG. 2B), which extracts the data (e.g., user identifier). Hence, the execution of the programming by the processor (element243ofFIG. 2B) further configures the eyewear device100to demodulate, via the VHF radio transceiver (element241ofFIG. 2B), the received VHF band radio modulated signals into data during reception.

As shown inFIGS. 1A-C, the eyewear device100is in a form for wearing by a user, which are eyeglasses in the example ofFIGS. 1A-C. The eyewear device100can take other forms and may incorporate other types of frameworks, for example, a headgear, a headset, or a helmet. In the eyeglasses example, eyewear device100includes a frame105including a left rim107A connected to a right rim107B via a bridge106adapted for a nose of the user (e.g., to contact the nose). The left and right rims107A-B include respective apertures175A-B, which hold a respective optical assembly180A-B. Optical assembly180A-B can include various optical layers176A-N and an image display device. The left and right temples125A-B extend from respective lateral sides of the frame105, for example, via respective left and right chunks110A-B. A substrate or materials forming the temple125A-B can include plastic, acetate, metal, or a combination thereof. The chunks110A-B can be integrated into or connected to the frame105on the lateral side

FIGS. 1B-Care rear views of example hardware configurations of the eyewear device100ofFIG. 1A, including two different placements of the magnetic coupler120. As shown inFIG. 1B, magnetic coupler120and magnetic coupler opening115are located on a right nose pad116B of bridge106and the magnetic coupler opening115is formed in the right nose pad116B. Nose pads116A-B are adapted to contact the nose of the user. As shown inFIG. 1C, the magnetic coupler120and magnetic coupler opening115are located on a portion of the left temple125A, which is in closer proximity to the left chunk110A. Typically, the VHF radio transceiver (element241ofFIG. 2B), envelope detector (element242ofFIG. 2B), processor (element243ofFIG. 2B), and other circuitry are located on at least one flexible printed circuit (PCBs) located in a chunk110A-B and temples125A-B. In one example, the VHF radio transceiver (element241ofFIG. 2B) is located in the left chunk110A and RF output (element225ofFIG. 2B) electrically connects the magnetic coupler120in the left temple125A to the VHF radio transceiver (element241ofFIG. 2B) in the left chunk110A. Having the magnetic coupler120located on a portion of the left temple125A, which is closer to the left chunk110A reduces the run of conductive trace(s), electrical interconnect(s)294, etc. forming the RF output (element225ofFIG. 2B).

Alternate placement locations for the magnetic coupler120on the eyewear device can be used individually or in combination. For example, multiple magnetic couplers120can be included in the eyewear device100to enhance VHF radio signal strength and reduce errors in the exchange of data (e.g., user identifiers). Additionally, the magnetic coupler120and magnetic coupler opening115can be located on other portions of the eyewear device100, including the right chunk110B; upper, middle, and lower portions of the rims107A-B; the various parts of the bridge106, including the left nose pad116A, or any other location on the temples125A-B. However, typically placement on the nose pads116A-B or portions of the temples125A-B that wrap around the ears of the users is ideal (e.g., just behind the ear). Touching of the skin by the magnetic coupler120exiting through the magnetic coupler opening115is preferred to an air gap, which reduces coupling efficiency. Coupling efficiency drops by R4depending on the size of the air gap. Whether an air gap exists or not, a cutout forms the magnetic coupler opening115in the eyewear device100allow the VHF radio waves to couple between the magnetic coupler120and human tissue of the user (element360ofFIG. 3), e.g., side of the human head.

As shown inFIGS. 1B-C, the eyewear device100can include two different types of image displays. In one example, the image display of optical assembly180A-B includes an integrated image display. An example of such an integrated image display is disclosed in FIG. 5 of U.S. Pat. No. 9,678,338, filed Jun. 19, 2015, titled “Systems and Methods for Reducing Boot Time and Power Consumption in Wearable Display Systems,” which is incorporated by reference herein. As shown inFIG. 1B, the optical assembly180A-B includes a suitable display matrix170of any suitable type, such as a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, or any other such display. The optical assembly180A-B also includes an optical layer or layers176, which can include lenses, optical coatings, prisms, mirrors, waveguides, optical strips, and other optical components in any combination. The optical layers176A-N can include a prism having a suitable size and configuration and including a first surface for receiving light from display matrix and a second surface for emitting light to the eye of the user. The prism of the optical layers176A-N extends over all or at least a portion of the respective apertures175A-B formed in the left and right rims107A-B to permit the user to see the second surface of the prism when the eye of the user is viewing through the corresponding left and right rims107A-B. The first surface of the prism of the optical layers176A-N faces upwardly from the frame105and the display matrix overlies the prism so that photons and light emitted by the display matrix impinge the first surface. The prism is sized and shaped so that the light is refracted within the prism and is directed towards the eye of the user by the second surface of the prism of the optical layers176A-N. In this regard, the second surface of the prism of the optical layers176A-N can be convex to direct the light towards the center of the eye. The prism can optionally be sized and shaped to magnify the image projected by the display matrix170, and the light travels through the prism so that the image viewed from the second surface is larger in one or more dimensions than the image emitted from the display matrix170.

In another example, the image display device of optical assembly180A-B includes a projection image display as shown inFIG. 1C. An example of a projection image display is disclosed in FIG. 6 of U.S. Pat. No. 9,678,338, filed Jun. 19, 2015, titled “Systems and Methods for Reducing Boot Time and Power Consumption in Wearable Display Systems,” which is incorporated by reference herein. The optical assembly180A-B includes a laser projector150, which is a three-color laser projector using a scanning mirror or galvanometer. During operation, an optical source such as a laser projector150is disposed in or on one of the temples125A-B of the eyewear device100. Optical assembly180-B includes one or more optical strips155A-N spaced apart across the width of the lens of the optical assembly180A-B or across a depth of the lens between the front surface and the rear surface of the lens.

As the photons projected by the laser projector150travel across the lens of the optical assembly180A-B, the photons encounter the optical strips155A-N. When a particular photon encounters a particular optical strip, the photon is either redirected towards the user's eye, or it passes to the next optical strip. A combination of modulation of laser projector150, and modulation of optical strips, may control specific photons or beams of light. In an example, a processor controls optical strips155A-N by initiating mechanical, acoustic, or electromagnetic signals. Although shown as having two optical assemblies180A-B, the eyewear device100can include other arrangements, such as a single or three optical assemblies, or the optical assembly180A-B may have arranged different arrangement depending on the application or intended user of the eyewear device100.

As further shown inFIGS. 1B-C, eyewear device100includes a left chunk110A adjacent the left lateral side170A of the frame105and a right chunk110B adjacent the right lateral side170B of the frame105. The chunks110A-B may be integrated into the frame105on the respective lateral sides170A-B (as illustrated) or implemented as separate components attached to the frame105on the respective sides170A-B. Alternatively, the chunks110A-B may be integrated into temples125A-B attached to the frame105.

FIG. 2Ashows an external side view of a temple of the eyewear device100ofFIG. 1Adepicting the magnetic coupler120. Right temple125B includes the magnetic coupler120, which is located inside the magnetic coupler opening115and can extend through the magnetic coupler opening115. For example, the magnetic coupler120protrudes through the magnetic coupler opening115to project through the magnetic coupler opening115and touches behind the ear of the user of the eyewear device100. Magnetic coupler120includes a VHF transmission or reception terminal (element560ofFIGS. 5A-C) that extends through the magnetic coupler opening115to contact the tissue of the user (element360ofFIG. 3). VHF transmission or reception terminal (element560ofFIGS. 5A-C) has a contour that does not bite into skin tissue of the user (element360ofFIG. 3), e.g., the contour is relatively flat. Alternatively or additionally, VHF transmission or reception terminal (element560ofFIGS. 5A-C) is flexible so to allow deformation when contact is made with the tissue of the user (element360ofFIG. 3). However, in some examples, the VHF transmission or reception terminal (element560ofFIGS. 5A-C) may not extend through or only partially extends through the magnetic coupler opening115to improve comfort of the user wearing the eyewear device100. Hence, the VHF transmission or reception terminal (element560ofFIGS. 5A-C) can be air gapped with the tissue of the user (element360ofFIG. 3) to enhance comfort if magnetic coupling efficiency is not a top priority.

FIG. 2Billustrates an internal side view of the components of the portion of temple of the eyewear device ofFIGS. 1A and 2Awith a cross-sectional view of a circuit board240with a VHF radio transceiver241, an envelope detector242, and a processor243. Although the circuit board240is a flexible printed circuit board (PCB), it should be understood that the circuit board240can be rigid in some examples. In some examples, the frame105or the chunk110A-B can include the circuit board240that includes the VHF radio transceiver241, the envelope detector242, and the processor243. In one example, VHF radio transceiver241and the envelope detector242are integrated in a system on chip (SOC), which includes a dedicated microprocessor integrated circuit (IC) along with volatile memory used by the microprocessor to operate. The system on a chip can be customized for converting data into RF signals and vice versa, which are conveyed to and from the magnetic coupler120, e.g., modulating and demodulating; and threshold comparison processing for the envelope detector242. In some examples, VHF radio transceiver241and envelope detector242may not be separate components, for example, functions and circuitry implemented in VHF radio transceiver241can be incorporated or integrated into the envelope detector242itself.

VHF radio transceiver241, envelope detector242, and processor243can be soldered on the circuit board240and are electrically connected via various electrically conductive traces, such as planar electrodes, and pads, which may be formed of metal or other conductive materials. Blind and through vias can be formed in the flexible PCB240and then electrical interconnects294can be used to electrically connect the VHF radio transceiver241, the envelope detector242, and the processor243to the magnetic coupler120. Machining operations may be used to form non-constant planar conductive traces, for example. In the example where the magnetic coupler120is located in the right temple125B, VHF radio transceiver241is connected to the magnetic coupler120through an RF output225line feed. RF output225line feed includes an electrical interconnect294, which is a conductive medium filling in a via in the flexible PCB240. Electrical interconnect294in turns connects to an electrically conductive trace295which, in turn connects to an electrically conductive pad296in the example.

In other examples, a chunk (elements110A-B ofFIGS. 1B-C), such as right chunk110B is integrated into or connected to the frame105on the right lateral side170B and the flexible printed circuit board (PCB)240is mounted inside the right chunk110B. VHF radio transceiver241and the processor243are disposed on the flexible PCB240. The driven element (element310ofFIG. 3) of the magnetic coupler120is electrically connected through RF output225line feed, which is formed one or more electrical interconnects294, electrically conductive traces295, or electrically conductive pads296to the VHF radio transceiver241. An envelope detector242is an electronic circuit that takes a VHF radio signal as input and provides a DC output, which is the envelope of the original VHF radio signal. Envelope detector242can include a rectifier circuit, which includes basic diode and low pass filter circuit. The capacitor in the rectifier circuit stores up charge on the rising edge and releases it slowly through the resistor when the signal falls. The diode in series rectifies the incoming VHF radio signal, allowing current flow only when the positive input terminal is at a higher potential than the negative input terminal. Either half-wave or full-wave rectification of the VHF radio signal can be utilized to convert the VHF radio input signal into a pulsed DC output signal. Hence, the envelope detector242can be used to detect the information stored in the envelope of VHF radio signals.

FIG. 3depicts a schematic view of operation of the magnetic coupler120placed on an inner side of the temple of the eyewear device100utilizing the human body as a conduit or antenna for RF signals330. During transmission, data from the processor (element243ofFIG. 2B) is conveyed to the VHF radio transceiver (element241ofFIG. 2B), which is modulated into VHF band radio modulated signals (RF signal330) that are conveyed from the VHF radio transceiver241through the electrical interconnect294to the electrical magnetic coupler120. Magnetic coupler radiates the VHF band radio modulated signals into the tissue of the user360wearing the eyewear device100. During transmission, as shown, the magnetic field335A is initially circumferential but then becomes a longitudinal magnetic field335D in the human body after wrapping around the magnetic coupler120and exiting VHF transmission or reception terminal (element560ofFIGS. 5A-C).

During reception, the magnetic coupler120absorbs the received VHF band radio modulated signals (RF signal330) from the tissue of the user360and conveys the VHF band radio modulated signals through the electrical interconnect294to the VHF radio transceiver (element241ofFIG. 2B). The tissue of the user360is on a head of a human body (element405B ofFIGS. 4A-B). Magnetic fields are induced in the magnetic coupler120from longitudinal received electric fields (elements436A-D ofFIGS. 4A-B) in the human body (element405B ofFIGS. 4A-B). Envelope detector (element242ofFIG. 2B) detects the strength (e.g., amplitude of the signals) received by the VHF radio transceiver (element241ofFIG. 2B), and if the strength exceeds a threshold, then the processor243(element243ofFIG. 2B), receives demodulated data from the VHF radio transceiver241. During reception, the magnetic coupler120absorbs the received VHF band radio modulated signals230as longitudinal electric fields (element436A-D ofFIGS. 4A-B) with magnetic field components at VHF transmission or reception terminal (element560ofFIGS. 5A-C).

As shown, magnetic coupler120is formed of a diamagnetic material305with high magnetic permeability. It should be appreciated that the magnetic coupler120is not to scale inFIG. 3, but is enlarged in size to depict its various electromechanical structures and electrical operation. Typically, diamagnetic materials have a magnetic permeability of 1 mu or less. In electromagnetism, permeability is the measure of the ability of a material to support the formation of a magnetic field within itself. Hence, permeability is the degree of magnetization that a material obtains in response to an applied magnetic field. Magnetic permeability is typically represented by the (italicized) Greek letter p (mu). In the example, diamagnetic material305includes ferrite and has a high magnetic permeability which is 10 mu or greater. Ferrite is a ceramic material made by mixing and firing large proportions iron (III) oxide (Fe2O3, rust) blended with small proportions of one or more additional metallic elements, such as barium, manganese, nickel, and zinc. Ferrite is both electrically non-conductive, meaning an insulator, and ferrimagnetic, meaning ferrite can easily be magnetized or attracted to a magnet. Ferrites can be divided into several families based on resistance to being demagnetized (magnetic coercivity). The families include hard ferrites that have high coercivity and are difficult to demagnetize, soft ferrites that have low coercivity and easily change their magnetization, and semi-hard ferrites that are in between. Diamagnetic material305is shaped to form the magnetic coupler120as a fraction or portion of a toroid, polyhedron, ellipsoid, or other quadric surface that is typically solid, but shaped with a hollow interior cavity space311to allow wrapping of driven element310(e.g., hollow interior cavity space311is a donut hole in the half-toroid example). In the example, the ferrite-based diamagnetic material305is shaped to form a half toroid. When the diamagnetic material305is a ferrite half toroid shape, the outer diameter may be about 4 millimeters (mm) because a six foot tall human provides sufficient length to radiate and absorb VHF radio signals in order to transmit and receive and transmit at that VHF wavelength.

As shown, magnetic coupler120includes a driven element310, which is an electrically conductive material. Driven element310connects to the diamagnetic material305and includes a conductive coil (e.g., formed of metal), which wraps around the diamagnetic material305(e.g., ferrite). Driven element is coupled to the VHF radio transceiver241, such as through the depicted electrically conductive pad296.

As shown inFIG. 3, eyewear device100includes at least one visible light camera314that is sensitive to the visible light range wavelength. Visible light camera314has a frontward facing field of view. Examples of such a visible light camera314include a high-resolution complementary metal-oxide-semiconductor (CMOS) image sensor and a video graphic array (VGA) camera, such as 640p (e.g., 640×480 pixels for a total of 0.3 megapixels), 720p, or 1080p. Image sensor data from the visible light camera314is captured along with geolocation data, digitized by an image processor (element612ofFIG. 6), stored in a memory (element634ofFIG. 6), and displayed on the image display device of optical assembly180A-B ofFIGS. 1A-C.

FIG. 4Adepicts an example of a pattern of transmitted electric fields435A-D of the RF signal230generated by a transmitting magnetic coupler120A of a first eyewear device100A worn on a head of a first human body405A. As shown, the transmitted magnetic fields435A-D of RF signal230are received by a receiving magnetic coupler120B on a second eyewear device100B worn on a head of a second human body405B during a fist bump400A greeting.FIG. 4Bdepicts an example of a pattern of electric fields435A-D of RF signal230generated by the transmitting magnetic coupler120A and received by the receiving magnetic coupler120B on the second human body405B. Transmitting magnetic coupler120A creates circumferential magnetic fields (elements335A-D ofFIG. 3) on the human head that in turn induce longitudinal electric fields (elements435A-D) on the first human body435A-D.

As noted, one such application of the eyewear devices100A-B with the magnetic couplers120A-B are to have the ability to transmit or even broadcast a user identifier and as the RF signal230. Thus, RF signal230can encodes user identifier (or other data) and the magnetic coupler120A induces the longitudinal transmitted electric fields435A-D in the first human body405B, which are then transferred into the second human body405B as the longitudinal received electric fields436A-D. VHF radio transceiver241can be tuned and optimized such that a user identifier or other data exchange can occur when the two people, such as the first human body405A and the second human body405B, wearing eyewear devices100A-B do a fist bump400A or handshake400B. Essentially, a ritual used when two people are introduced, greet, or interact with each other, can be used to introduce and have their digital personas interact.

InFIGS. 4A-B, when clothes and skin are touching each other, the RF energy flowing through jumps to the other person during the fist bump400A or handshake400B. However, if the hands of the human bodies405A-B are in a closed position, as is the case with a fist bump400A instead of the handshake400B, there is a 10 decibel drop in coupling. In bothFIGS. 4A-B, the human bodies405A-B are utilized as transmitting and receiving VHF conduits, but in other examples the human bodies405A-B can be used as a transmitting and receiving wireless antennas if driven with higher power VHF energy. In the wireless antenna mode, the human bodies405A-B can be five feet away with no skin-to-skin contact, so higher power VHF energy is emitted by the transmitting magnetic coupler120A, which means increased power is drained by the VHF radio transceiver241from the power source (e.g., battery). Wireless antenna mode for the human bodies405A-B can be useful in certain environments, e.g., broadcasting user identifiers at a music festival. However, in conduit mode, the human bodies405A-B engage in direct skin-to-skin contact, so the VHF radio transceiver (element241ofFIG. 2B) operates on low energy, which conserves battery power in the eyewear device100(e.g., far lower than Bluetooth®), which is better suited to business or face-to-face meetings.

In some examples, the frame105, bridge,106, rims107A-B, and temples125A-B of the eyewear device100can be formed of acetate. However, because of the magnetic coupler opening120, e.g., cutout in the component(s), there is virtually no loss of RF signal230. VHF transmission or reception terminal (element560ofFIGS. 5A-C) exiting the magnetic coupler opening120in the right temple125B or nose pad116B of bridge106can be cut to allow the VHF transmission or reception terminal560to touch the skin tissue of the user (element360ofFIG. 3). In some examples, an air gap (e.g., space) may be formed between the VHF transmission or reception terminal (element560ofFIG. 5) and the skin tissue of the user (element360ofFIG. 3). However, the magnetic coupling efficiency drops by R4depending on size of the air gap. Hence, magnetic coupling occurs but not as efficiently, meaning the VHF radio transceiver (element241ofFIG. 2B) may need more power.

Electromagnetic waves are circumferential as they wrap around the driven element310of magnetic coupler120and are then transformed into longitudinal electromagnetic fields335A-D when exiting driven element310into the tissue of the user360. Conventional VHF is typically high powered, such as FM radio, hence a Federal Communications Commission (FCC) license is needed. However, the VHF radio transceiver241can be driven with less 100 milliwatts (mW) of power, which does not require an FCC license. At VHF frequencies, the human body radiates energy. In contrast, with UHF frequencies (e.g., Bluetooth® or WiFi) the human body absorbs RF energy, which causes temperature rise, meaning UHF is not that great from a physical and scientific standpoint, but is freely provided by the FCC.

Diamagnetic material305of magnetic coupler120is formed into a half circle, half toroid, or U-block shape. A half circle shape allows the VHF transmission or reception terminal (element560ofFIGS. 5A-C), which has a termination surface, to be flat against and flush with the tissue of the user360on the head of the human body. Diamagnetic material305can shaped into a third or quarter circle (or other fraction), for example, but needs to be machined to match the shape of the tissue of the user360. For fast coupling, the diamagnetic material305typically touches skin tissue of the user360without causing a feeling that the diamagnetic material305is biting into the skin tissue of the user360. As used herein, U-block shape means a curved body with two lateral arms. One of the ends of the arms of the U-block includes the VHF transmission or reception terminal (element560ofFIGS. 5A-C). The shape of the diamagnetic material305does not have to be curved, e.g., can be like a cube which is hollowed out and cut into two or a half polygon that is hollowed to allow wrapping around, or other fraction or portion thereof.

A low power microcontroller of the VHF radio transceiver241of the receiving human body405A reads a converted DC signal, which is generated by the envelope detector (element242ofFIG. 2B) from the received VHF energy waves, such as received electric fields436A-D. In one example, the envelope detector (element242ofFIG. 2B) includes circuitry, such as a rectifier circuit that comprises a diode detector, a capacitor, and a resistor; and the lower power microcontroller reads the converted DC signal. If the converted DC signal is strong enough, VHF radio transceiver241demodulates data from the corresponding VHF waves. If the DC signal is not strong enough, the corresponding VHF waves are discarded by the VHF radio transceiver241. The VHF radio signal comes in through the magnetic coupler opening115in the right temple125B, then travels to the receiving magnetic coupler120B, including the driven element310and then to the diode of envelope detector (element242ofFIG. 2B). Diode detects the peak of the sinusoidal VHF radio signal and converts the sinusoidal VHF radio signal into a DC signal, which is the peak. Diode is coupled to the capacitor to detect the peak, and the stronger the sinusoidal signal, the higher the DC signal output from the rectifier circuit. Microcontroller then interrogates the DC signal output to determine whether VHF radio transceiver241should demodulate into data. For example, a DC signal of one millivolts is discarded, but ½ volt is processed because it means human bodies405A-B are fist-bumping400A or handshaking400B.

In one example, a front end of the VHF radio transceiver241of eyewear device100A sends an extremely low power signal that is modulated with the wearer's (first human body405A) user identifier transmitting magnetic coupler120A. The magnetic coupler120A can include a half toroid shaped diamagnetic material formed ferrite to create time varying circumferential magnetic fields. Because of electromagnetic physics, time varying transmitted electrical fields435A-D are generated along the height of the human body are from these circumferential magnetic fields. The induced transmitted electrical fields435A-D then radiate off the first human body405A. When transmitted electrical fields435A-D come in contact with another human body, such as the second human body405B the coupling is maximized. The result is creation of secondary time varying electric fields on the person who contacted the transmitting individual, shown as the received electrical fields436A-D, on the second human body405B. These time varying electric fields in turn create a time varying magnetic field, which is picked up by the ferrite based half toroid magnetic coupler120B of the receiving eyewear device100B worn on the second human body405B. The incident magnetic field generates a current and wakes up the receiver circuit of the VHF radio transceiver241, which demodulates the VHF radio signal to obtain the user identifier that was transmitted by the first human body405A. The transmitted data is not limited to user identifiers, and may various data types and content, such as video, pictures, audio, etc.

FIG. 5Ais a cross-sectional view taken through the magnetic coupler120and the temple of the eyewear device ofFIGS. 1A and 2A-B. As shown, the magnetic coupler opening115is placed on the inner side, shown as inward facing surface530, of the right temple125B or the bridge (element106ofFIG. 1B) of eyewear device100, to enhance coupling with the wearer of the eyewear device100. Magnetic coupler120creates circumferential magnetic fields on the human head that in turn induce longitudinal electric fields on the human body. Magnetic coupler120can operate at VHF band and is connected to a low power VHF transceiver241, for example, with an output power less than 100 milliwatts of power (Pout<100 mW). Magnetic coupler120is made from a material with high permeability (mu>10) and has the shape of a half circle, half toroid, or a U-block. In some implementations, magnetic coupler opening115may be formed in the outward facing surface535, for example, applications in which high power consumption is permitted and highly efficient coupling to the human body is not as desirous (e.g., broadcasting data to many users wearing eyewear devices100A-N).

During transmission, the magnetic coupler120radiates the transmitted VHF band radio modulated signals230as circumferential magnetic fields (element335A-D ofFIG. 3) at the RF transmission or reception terminal560, which cause longitudinal transmitted electric fields (elements435A-D ofFIGS. 4A-B) in the first human body (element405A ofFIGS. 4A-B). During reception, the magnetic coupler120absorbs the received VHF band radio modulated signals230as longitudinal received electric fields (element436A-D ofFIGS. 4A-B) in the second human body (element405B ofFIGS. 4A-B) at the RF transmission or reception terminal560.

As shown inFIG. 5A, diamagnetic material305is shaped into a half toroid in the right temple125B, which enables the human body to be utilized as a conduit (e.g., feed system) or antenna for VHF signals. The human body is not very conductive (e.g., conductive energy is reflected back), but the diamagnetic material305with high permeability (e.g., ferrite) can adjust the VHF electromagnetic energy from the RF output (element225ofFIG. 2A) to be orthogonal to the human body at the VHF transmission or reception terminal560. VHF transmission or reception terminal560then couples the VHF energy to the tissue of the user360. Typically, high permeability means 10 mu or greater. Permeability is the ability of the diamagnetic material305to hold on to a magnetic field. Diamagnetic material305may be formed of, among other things, ferrite, which includes ceramic with mixed oxide and iron. Iron increases permeability and is not conductive, but has a high ability to hold on to the magnetic field.

Driven element310includes an electrically conductive coil connected to the VHF radio transceiver241via the RF output225, which can include an RF strip line to receive radio input. RF signal230comprises sinusoidal alternating current (AC) waves, alternating between positive and negative. Driven element310is connected to the VHF radio transceiver241and, during transmission mode as shown inFIG. 5C, current flows in and through the driven element310by entering from one side (e.g., conductive pad296) and exiting through the other side (e.g., VHF transmission or reception terminal560). The current flows in reverse during reception mode, as shown inFIG. 5B. Because driven element310includes a conductive coil, the driven element310creates a high variance magnetic field. After passing through the magnetic coupler120, the magnetic field goes from the top of the paper to the bottom of the paper such that the magnetic field parallel to page. The ferrite forming the diamagnetic material305can be a half toroid or U-shape to confines and trap VHF radio energy inside. When VHF radio energy enters the magnetic coupler120at the conductive pad296, the magnetic field is parallel, and when the magnetic field exits at the VHF transmission or reception terminal560and passes through the magnetic coupler opening115, the magnetic fields are orthogonal to the paper. Once the magnetic fields are coupled to the human body, the entire human body radiates VHF radio waves, and the human body behaves like a monopole or dipole antenna.

As noted above, the RF signal230enters in through the coil of driven element310, which is coupled to the ferrite half toroid shaped diamagnetic material305. Ferrite can be deposited in the eyewear device100, but is typically a three dimensional structure that is cut in half and then embedded inside plastic of the left or right temples125A-B of the eyewear device100or in the left or right nose pads116A-B of bridge106. Driven element310is soldered on the flexible PCB (element240ofFIG. 2B) and the ferrite diamagnetic material305is held in place by a plastic molding around it. The driven element310is formed of metal and soldered, but since ferrite is nonconductive, it is not soldered. The coil of driven element310wraps around the diamagnetic material305(e.g., half toroid shape) along the entire half toroid shape, but driven element310can be squeezed in the middle of the diamagnetic material305in some examples. Hence, while the diamagnetic material305goes through the inside of the driven element310in the example, this can be switched so that the driven element310is inside the diamagnetic material305. Having the driven element310inside the diamagnetic material305may be more difficult to manufacture, but improves VHF coupling efficiency.

When the RF signal230flows through the driven element310during transmission, the RF signal is confined inside the diamagnetic material305. The magnetic field changes shape when passing through the diamagnetic material305because when wrapping around the coil of driven element310, the magnetic field has to follow the shape of the half toroid shaped diamagnetic material305(e.g., ferrite). Thus, the magnetic fields become orthogonal to the human head. Hence, the diamagnetic material305behaves like a circuit and the magnetic fields have to exit and go to the other side where the diamagnetic material305touches human skin at the VHF transmission or reception terminal560through the magnetic coupler opening115. The only way magnetic fields can exit the magnetic coupler120is to flow through the human body.

FIG. 5Bshows operation and a circuit diagram of the magnetic coupler120ofFIGS. 1A-Cand2A-B, the VHF radio transceiver241, the envelope detector242, and the processor243during reception of RF signals230, such as VHF band radio modulated signals. Magnetic coupler120absorbs received VHF band radio modulated signals as longitudinal magnetic fields at the RF transmission or reception terminal560. For example, the tissue of the user (element360ofFIG. 3) that absorbs the received VHF band radio modulated signals is on a head of a human body (element405B ofFIGS. 4A-B). Received VHF band radio modulated signals absorbed by the magnetic coupler120propagate through an RF output225line to the VHF radio transceiver241. As noted previously, the RF output225line includes electrical interconnect(s)294, electrically conductive trace(s)295, and electrically conductive pad(s)296to convey RF signals230, such as the received VHF band radio modulated signals.

Envelope detector circuit242is integrated into or connected to the VHF radio transceiver241and connected to the processor243. In an example, the envelope detector242is configured to detect a peak of a sinusoid of the received VHF band radio modulated signals. For example, the envelope detector circuit242includes a rectifier circuit to convert the sinusoid of the received VHF band radio modulated signals into a direct current (DC) output signal. In the example ofFIG. 5B, the VHF radio transceiver241actually includes an internal microcontroller that is separate from processor243. The microcontroller of the VHF radio transceiver241interrogates the DC output signal by comparing the converted DC output signal to a DC threshold to determine whether the received VHF band radio modulated signals are intended for the user. In response to determining the DC output signal satisfies the DC threshold meaning the received VHF band radio modulated signals are intended for the user, the VHF radio transceiver241demodulates, the received VHF band radio modulated signals into data during reception. VHF radio transceiver241then conveys the demodulated data to the processor243. Processor243then converts the received data into a user identifier.

In other examples, VHF radio transceiver241may not include the separate microcontroller and processor243itself may interrogate the converted DC output signal and determine whether the VHF band radio modulated signals230are intended for the user. In the example, VHF radio transceiver241is a low power FM transceiver that operates at less than 100 milliwatts. Envelope detector242allows the VHF radio transceiver241to turn on and demodulate VHF band radio modulated signals when the incident current and voltage exceeds certain thresholds. These thresholds can correspond to coupling levels that occur when two human bodies405A-B fist bump400A, shake hands400B, or engage in other skin-to-skin contact (e.g., hug or kiss).

FIG. 5Cshows operation and a circuit diagram of the magnetic coupler ofFIGS. 1A-Cand2A-B, the VHF radio transceiver241, the envelope detector242, and the processor243during transmission of RF signals230. The operation, such as the conveying of RF signals is like that of the reception mode ofFIG. 5B, but in reverse. However, the envelope detector242is not utilized during the transmission mode.

As shown, the processor243conveys a user identifier for modulation into an RF signal230. The RF signal230is conveyed via the RF output line225, which includes electrical interconnect294, conductive trace295, and electrically conductive pad296to the magnetic coupler120. During transmission, the radiated circumferential magnetic fields (elements335A-D ofFIG. 3) from the VHF transmission or reception terminal560induce longitudinal electric fields (elements435A-D ofFIGS. 4A-B) in the tissue of the user (element360ofFIG. 3). For example, the tissue of the user360is on a head of a human body (element405A ofFIGS. 4A-B). During transmission, the magnetic coupler120radiates circumferential magnetic fields (elements335A-D ofFIG. 3) at the RF transmission or reception terminal560on the head. The magnetic fields335A-D are initially parallel but then bend as the magnetic fields335A-D become perpendicular to the human body405A and circumferential. Hence, the length of the human body405A can become a VHF conduit (e.g., analogous to a line feed) or an antenna, in some examples. If the magnetic coupler120is rotated 90 degrees, the girth or circumference of the human body will radiate VHF radio energy. However, generally humans are taller than they are wide, so the depicted orientation of the magnetic coupler120provides better magnetic coupling efficiency.

FIG. 6is a high-level functional block diagram of an example magnetic coupler system600. The magnetic coupler system600includes eyewear device100, mobile device690, and server system698. Mobile device690may be a smartphone, tablet, laptop computer, access point, or any other such device capable of connecting with eyewear device100using both a low-power wireless connection625and a high-speed wireless connection637. Mobile device690is connected to server system698and network695. The network695may include any combination of wired and wireless connections.

Server system698may be one or more computing devices as part of a service or network computing system, for example, that include a processor, a memory, and network communication interface to communicate over the network695with the mobile device690and eyewear device100. The memory of the server system698can include user identifiers or other data transmitted or received by the magnetic coupler120of the eyewear device100, and then sent via the depicted networks625,637,695. The memory of the server system698can also include a database of user identifiers for users of the chat application650to perform functions of the programming described herein that utilize the VHF radio transceiver241and magnetic coupler120to exchange user identifiers or other data (e.g., images, videos, audio). Chat application650may transmit received user identifiers to a host computer (e.g., mobile device690and server system698) to retrieve profile information based on the received user identifier. For example, when a user of the eyewear device100receives a user identifier via a handshake or a fist bump, the chat application650may request that the server system698resolve the user identifier to a particular username.

Mobile device690and elements of network695, low-power wireless connection625, and high-speed wireless architecture637may be implemented using details of the architecture of mobile device690, for example utilizing the short range XCVRs and WWAN XCVRs of mobile device690described inFIG. 7.

Low-power wireless circuitry624and the high-speed wireless circuitry636of the eyewear device100can include short range transceivers (Bluetooth®) and wireless wide, local, or wide area network transceivers (e.g., cellular or WiFi). Mobile device690, including the transceivers communicating via the low-power wireless connection625and high-speed wireless connection637, may be implemented using details of the architecture of the eyewear device100, as can other elements of network695.

Output components of the eyewear device100include visual components, such as the image display of the optical assembly180as described inFIGS. 1B-C(e.g., a display such as a liquid crystal display (LCD), a plasma display panel (PDP), a light emitting diode (LED) display, or a projector). The image display of the optical assembly180is driven by the image display driver642. The output components of the eyewear device100further include acoustic components (e.g., speakers), haptic components (e.g., a vibratory motor), other signal generators, and so forth. The input components of the eyewear device100and various components of the system, including the mobile device690and server system698, may include alphanumeric input components (e.g., a keyboard, a touch screen configured to receive alphanumeric input, a photo-optical keyboard, or other alphanumeric input components), point-based input components (e.g., a mouse, a touchpad, a trackball, a joystick, a motion sensor, or other pointing instruments), tactile input components (e.g., a physical button, a touch screen that provides location and force of touches or touch gestures, or other tactile input components), audio input components (e.g., a microphone), and the like.

System600may optionally include additional peripheral device elements619. Such peripheral device elements619may include biometric sensors, additional sensors, or display elements integrated with eyewear device100. For example, peripheral device elements1119may include any I/O components including output components, motion components, position components, or any other such elements described herein.

For example, the biometric components of the system include components to detect expressions (e.g., hand expressions, facial expressions, vocal expressions, body gestures, or eye tracking), measure biosignals (e.g., blood pressure, heart rate, body temperature, perspiration, or brain waves), identify a person (e.g., voice identification, retinal identification, facial identification, fingerprint identification, or electroencephalogram based identification), and the like. The motion components include acceleration sensor components (e.g., accelerometer), gravitation sensor components, rotation sensor components (e.g., gyroscope), and so forth. The position components include location sensor components to generate location coordinates (e.g., a Global Positioning System (GPS) receiver component), WiFi or Bluetooth® transceivers to generate positioning system coordinates, altitude sensor components (e.g., altimeters or barometers that detect air pressure from which altitude may be derived), orientation sensor components (e.g., magnetometers), and the like. Such positioning system coordinates can also be received over wireless connections625and637from the mobile device690via the low-power wireless circuitry624or high-speed wireless circuitry636

Eyewear device100includes visible light camera314, image display of the optical assembly180, VHF radio transceiver241, envelope detector242, processor243, image processor612, low-power circuitry620, and high-speed circuitry630. Image processor612includes circuitry to receive signals from the visible light camera314and process those signals from the visible light camera314into a format suitable for storage in the memory834. The components shown inFIG. 6for the eyewear device100are located on one or more circuit boards, for example a PCB or flexible PCB, in the temples125A-B. Alternatively or additionally, the depicted components can be located in the chunks110A-B, frame105, hinges126A-B, or bridge106of the eyewear device100. Visible light camera314can include digital camera elements such as a complementary metal-oxide-semiconductor (CMOS) image sensor, charge coupled device, a lens, or any other respective visible or light capturing elements that may be used to capture data.

Memory634includes various received user identifiers, the user identifier of the wearer of the eyewear device100, and a chat application650. Chat application650performs functions to transmit or receive via the magnetic coupler120, such as to exchange user identifiers, e.g., during a handshake or fist bump, as outlined herein. Chat application650stored on the eyewear device100and mobile device690may be executed by a processor243A-B of the eyewear device100or the mobile device690and utilize the corresponding user account information to post or send images and videos captured by the visible light camera314of the eyewear device100to the user's account and deliver the images and videos captured by the visible light camera314to contacts or associated groups of the verified user in the chat application650(e.g., as a result of exchanging user identifiers via magnetic coupler120). It should be understood that various other types of applications may user the magnetic coupler120for user identifier transmission and the transmitted data can be any type of data, not just user identifiers, e.g., audio, video, images, etc. Although the above example describes exchanging user identifiers to obtain the identity of a user (e.g., a contact) as knowing their identity or identifying an associated user account, some embodiments can include transmitting images and videos captured by the visible light to camera314via the magnetic coupler120to another user's eyewear device100B during a handshake or fist bump. Although shown as an application, it should be understood that the chat application650can be part of the operating system stored in the memory634of the eyewear device100that provides an application programming interface (API) which is responsive to calls from other applications.

Image processor612, VHF radio transceiver241, and envelope detector242are structured within eyewear device100such that the components may be powered on and booted under the control of low-power circuitry620. Image processor612, VHF radio transceiver241, and envelope detector242may additionally be powered down by low-power circuitry620. Depending on various power design elements associated with image processor612, VHF radio transceiver241, and envelope detector242, these components may still consume a small amount of power even when in an off state. This power will, however, be negligible compared to the power used by image processor612, VHF radio transceiver241, and envelope detector242when in an on state, and will also have a negligible impact on battery life. As described herein, device elements in an “off” state are still configured within a device such that low-power processor243A is able to power on and power down the devices. A device that is referred to as “off” or “powered down” during operation of eyewear device100does not necessarily consume zero power due to leakage or other aspects of a system design.

In one example embodiment, image processor612comprises a microprocessor integrated circuit (IC) customized for processing sensor data from the visible light camera314, along with volatile memory used by the microprocessor to operate. In order to reduce the amount of time that image processor612takes when powering on to processing data, a non-volatile read only memory (ROM) may be integrated on the IC with instructions for operating or booting the image processor612. This ROM may be minimized to match a minimum size needed to provide basic functionality for gathering sensor data from visible light camera314, such that no extra functionality that would cause delays in boot time are present. The ROM may be configured with direct memory access (DMA) to the volatile memory of the microprocessor of image processor612. DMA allows memory-to-memory transfer of data from the ROM to system memory of the image processor612independent of operation of a main controller of image processor612. Providing DMA to this boot ROM further reduces the amount of time from power on of the image processor612until sensor data from the image processor612, VHF radio transceiver241, and envelope detector242can be processed and stored. In certain embodiments, minimal processing of the camera signal from the visible light camera314is performed by the image processor612, and additional processing may be performed by applications operating on the mobile device690or server system698.

Low-power circuitry620includes low-power processor243A and low-power wireless circuitry624. These elements of low-power circuitry620may be implemented as separate elements or may be implemented on a single IC as part of a system on a single chip. Low-power processor243A includes logic for managing the other elements of the eyewear device100. Low-power processor243A may also be configured to receive input signals or instruction communications from mobile device690via low-power wireless connection625. Additional details related to such instructions are described further below. Low-power wireless circuitry624includes circuit elements for implementing a low-power wireless communication system via a short-range network. Bluetooth® Smart, also known as Bluetooth® low energy, is one standard implementation of a low power wireless communication system that may be used to implement low-power wireless circuitry624. In other embodiments, other low power communication systems may be used.

High-speed circuitry630includes high-speed processor243B, memory634, and high-speed wireless circuitry636. VHF radio transceiver241and envelope detector242can be coupled to the low-power circuitry620and operated by the low-power processor243B. However, it should be understood that in some examples the VHF radio transceiver241and envelope detector242can be coupled to the high-speed circuitry630and operated by the high-speed processor243B. In the example, the image display driver642is coupled to the high-speed circuitry630and operated by the high-speed processor243B in order to drive the image display of the optical assembly180.

High-speed processor243B may be any processor capable of managing high-speed communications and operation of any general computing system needed for eyewear device100. High speed processor243B includes processing resources needed for managing high-speed data transfers on high-speed wireless connection637to a wireless local area network (WLAN) using high-speed wireless circuitry636. In certain embodiments, the high-speed processor243B executes an operating system such as a LINUX operating system or other such operating system of the eyewear device100and the operating system is stored in memory634for execution. In addition to any other responsibilities, the high-speed processor243B executing a software architecture for the eyewear device100is used to manage data transfers with high-speed wireless circuitry636. In certain embodiments, high-speed wireless circuitry636is configured to implement Institute of Electrical and Electronic Engineers (IEEE) 602.11 communication standards, also referred to herein as Wi-Fi. In other embodiments, other high-speed communications standards may be implemented by high-speed wireless circuitry636.

Memory634includes any storage device capable of storing various data and applications, including, among other things, the depicted the user identifiers, chat application650, camera data generated by the visible light camera314and the image processor612, as well as images generated for display by the image display driver642on the image display of the optical assembly180. While memory634is shown as integrated with high-speed circuitry630, in other embodiments, memory634may be an independent standalone element of the eyewear device100. In certain such embodiments, electrical routing lines may provide a connection through a chip that includes the high-speed processor243B from the image processor612or low-power processor243A to the memory634. In other embodiments, the high-speed processor243B may manage addressing of memory634such that the low-power processor243A will boot the high-speed processor243B any time that a read or write operation involving memory634is needed.

As noted above, eyewear device100may include cellular wireless network transceivers or other wireless network transceivers (e.g., WiFi or Bluetooth®), and run sophisticated applications. Some of the applications may include email application, phone application to place phone calls, web browser application to navigate the Internet, banking application, video or image codecs to watch videos or interact with pictures, codecs to listen to music, a turn-by-turn navigation application, an augmented or virtual reality application, etc.

In an example of reception mode, the eyewear device100is connected to a mobile device690via a network625or637, for example, the network is a wireless short-range network625or a wireless local area network637. Execution of the programming (chat application650) by the processor243A-B configures the eyewear device100to perform further functions, including functions to receive, via the network625or637, from the mobile device690a user identifier of the user. Execution of the programming (chat application650) by the processor243A-B further configures the eyewear device100to store the user identifier in the memory634. Execution of the programming (chat application650) by the processor243A-B further configures the eyewear device100to modulate, via the VHF radio transceiver241, the VHF band radio carrier signal with the user identifier to generate the transmitted VHF band radio modulated signals during transmission.

In an example of transmission mode, the eyewear device100is connected to a mobile device690via a network625or637, for example, the network is a wireless short-range network625or a wireless local area network637. Execution of the programming (chat application650) by the processor243A-B configures the eyewear device100to perform further functions, including functions to demodulate, via the VHF radio transceiver241, the received VHF band radio modulated signals into a user identifier during reception. Execution of the programming (chat application650) by the processor243A-B further configures the eyewear device100to transmit, via the network625or637, to the mobile device the user identifier to the mobile device.

Although described in terms of eyewear device100, it should be understood that other wearable devices and mobile device690can incorporate the magnetic coupler120, magnetic coupler opening115, VHF radio transceiver241, envelope detector242, etc. in a manner similar to the eyewear device100. For example, the wearable device or mobile device690includes a frame and a magnetic coupler opening120formed in the frame. Wearable device or mobile device690further includes a processor243A-B, a memory634accessible to the processor, and a very high frequency (VHF) radio transceiver for data transmission and reception and connected to the processor. VHF radio transceiver241includes a transmitter to modulate a VHF band radio carrier signal with data to generate transmitted VHF band radio modulated signals during transmission. VHF radio transceiver241further includes a receiver to demodulate received VHF band radio modulated signals into data during reception. Wearable device or mobile device690further includes a magnetic coupler120connected to the VHF radio transceiver241.

Magnetic coupler120includes a diamagnetic material305shaped to form a VHF transmission or reception terminal560that partially or fully aligns with the magnetic coupler opening115. During transmission, magnetic coupler120is configured to radiate the transmitted VHF band radio modulated signals into tissue of the user360. During reception, magnetic coupler120is configured to absorb the received VHF band radio modulated signals from the tissue of the user360. Wearable device or mobile device690further includes a memory634accessible to the processor243A-B and programming in the memory634. Magnetic coupler120includes a driven element310and the driven element310connects to the diamagnetic material305. Diamagnetic material305has a high magnetic permeability, which is greater than 10 mu and the diamagnetic material305is shaped to form a fraction of a toroid, polyhedron, ellipsoid, or other quadric surface that is typically solid. Diamagnetic material305can be shaped with a hollow interior cavity space311to allow wrapping of driven element310(e.g., hollow interior cavity space311is a donut hole in the half-toroid example). For example, the diamagnetic material305includes ferrite, the driven element310includes a conductive coil, which wraps around the ferrite, and the ferrite is shaped to form a half toroid. The RF transmission or reception terminal560extends through the magnetic coupler opening115to contact the tissue of the user360.

As described, the disclosed VHF band technology offers certain benefits that is hard to accomplish at UHF band, specifically in the areas of power consumption and electrical design simplicity. An RF front end (RFFE) like the VHF radio transceiver241optimized to operate in the VHF band that is more efficient than the one optimized in the UHF band (such as WiFi or Bluetooth®) due to the electrical characteristics of modern semiconductors. While the VHF spectrum is more crowded and the bandwidth is more limited compared to UHF bands, low power transmission of radio signals, such as in the FM band, which ranges from approximately 87.5 MHz to 108.0 MHz, in 200 kHz steps, can be utilized in several examples by the VHF radio transceiver241and magnetic coupler120. The magnetic coupler120of eyewear device100utilizes the human body to work as a VHF conduit (e.g., analogous to a line feed) or antenna when properly connected to the VHF radio transceiver241, and is more power efficient than other popular technologies like Bluetooth® or WiFi.

Coupling between the human body and the RFFE of the VHF radio transceiver241in the eyewear device100is made as strong as possible to maximize the system efficiency. In one example, the magnetic coupler120is comprised of diamagnetic material305that is a half-toroid structure made out of ferrite material with low loss and high permeability. Open tips of the toroid shaped diamagnetic material305, such as the VHF transmission or reception terminal560, can touch the skin or other tissue of the user360. This design enables the VHF magnetic fields to be captured by the half toroid shaped magnetic coupler120at maximum efficiency. Due to the high permeability of ferrite material, the disclosed design locks the magnetic fields inside, reduces leakage, and delivers the maximum energy to the front end of the VHF radio transceiver241. The ideal design can be a half toroid; however, a U-shaped structure also works as intended. The surface area of the ferrite toroid diamagnetic material305where it touches the skin tissue of the user360can be as large as possible to extract the maximum amount of VHF signal from the human body. In addition, the number of turns a driven element310(e.g., conductive coil) can be maximized to optimize the coupling efficiency. There are some limitations from the industrial design and usability perspectives so a tradeoff will be made in the final design between size and best fit of the eyewear device100.

FIG. 7shows an example of a hardware configuration for the mobile device690of the magnetic coupler system600ofFIG. 6, in simplified block diagram form. The mobile device690can incorporate the magnetic coupler120, magnetic coupler opening115, VHF radio transceiver241, envelope detector242in a manner similar to the eyewear device100previously described. Shown are elements of a touch screen type of mobile device690having a chat application650loaded, although other non-touch type mobile devices can be used in the user authorization communications and controls under consideration here. Examples of touch screen type mobile devices that may be used include (but are not limited to) a smart phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or other portable device. However, the structure and operation of the touch screen type devices is provided by way of example; and the subject technology as described herein is not intended to be limited thereto. For purposes of this discussion,FIG. 7therefore provides a block diagram illustration of the example mobile device690having a touch screen display for displaying content and receiving user input as (or as part of) the user interface. Mobile device690also includes a camera(s)770, such as visible light camera(s).

The activities that are the focus of discussions here typically involve data communications. As shown inFIG. 7, the mobile device690includes at least one digital transceiver (XCVR)710, shown as WWAN XCVRs, for digital wireless communications via a wide area wireless mobile communication network. The mobile device690also includes additional digital or analog transceivers, such as short range XCVRs720for short-range network communication, such as via NFC, VLC, DECT, ZigBee, Bluetooth®, or WiFi. For example, short range XCVRs720may take the form of any available two-way wireless local area network (WLAN) transceiver of a type that is compatible with one or more standard protocols of communication implemented in wireless local area networks, such as one of the Wi-Fi standards under IEEE 802.11 and WiMAX.

To generate location coordinates for positioning of the mobile device690, the mobile device690can include a global positioning system (GPS) receiver. Alternatively, or additionally the mobile device690can utilize either or both the short range XCVRs720and WWAN XCVRs710for generating location coordinates for positioning. For example, cellular network, WiFi, or Bluetooth® based positioning systems can generate very accurate location coordinates, particularly when used in combination. Such location coordinates can be transmitted to the eyewear device100over one or more network connections via XCVRs720.

The transceivers710,720(network communication interface) conforms to one or more of the various digital wireless communication standards utilized by modern mobile networks. Examples of WWAN transceivers710include (but are not limited to) transceivers configured to operate in accordance with Code Division Multiple Access (CDMA) and 3rd Generation Partnership Project (3GPP) network technologies including, for example and without limitation, 3GPP type 2 (or 3GPP2) and LTE, at times referred to as “4G.” For example, the transceivers710,720provide two-way wireless communication of information including digitized audio signals, still image and video signals, web page information for display as well as web related inputs, and various types of mobile message communications to/from the mobile device690for user identification strategies.

Several of these types of communications through the transceivers710,720and a network, as discussed previously, relate to protocols and procedures in support of communications with the eyewear device100or the server system698for user identification. Such communications, for example, may transport packet data via the short range XCVRs720over the wireless connections625and637to and from the eyewear device100as shown inFIG. 6. Such communications, for example, may also transport data utilizing IP packet data transport via the WWAN XCVRs710over the network (e.g., Internet)695shown inFIG. 6. Both WWAN XCVRs710and short range XCVRs720connect through radio frequency (RF) send-and-receive amplifiers (not shown) to an associated antenna (not shown).

The mobile device690further includes a microprocessor, shown as CPU730, sometimes referred to herein as the host controller. A processor is a circuit having elements structured and arranged to perform one or more processing functions, typically various data processing functions. Although discrete logic components could be used, the examples utilize components forming a programmable CPU. A microprocessor for example includes one or more integrated circuit (IC) chips incorporating the electronic elements to perform the functions of the CPU. The processor730, for example, may be based on any known or available microprocessor architecture, such as a Reduced Instruction Set Computing (RISC) using an ARM architecture, as commonly used today in mobile devices and other portable electronic devices. Of course, other processor circuitry may be used to form the CPU730or processor hardware in smartphone, laptop computer, and tablet.

The microprocessor730serves as a programmable host controller for the mobile device690by configuring the mobile device690to perform various operations, for example, in accordance with instructions or programming executable by processor730. For example, such operations may include various general operations of the mobile device, as well as operations related to user identifier communications with the eyewear device100and server system698. Although a processor may be configured by use of hardwired logic, typical processors in mobile devices are general processing circuits configured by execution of programming.

The mobile device690includes a memory or storage device system, for storing data and programming. In the example, the memory system may include a flash memory740A and a random access memory (RAM)740B. The RAM740B serves as short term storage for instructions and data being handled by the processor730, e.g. as a working data processing memory. The flash memory740A typically provides longer term storage.

Hence, in the example of mobile device690, the flash memory740A is used to store programming or instructions for execution by the processor730. Depending on the type of device, the mobile device690stores and runs a mobile operating system through which specific applications, including chat application650. Applications, such as the chat application650, may be a native application, a hybrid application, or a web application (e.g., a dynamic web page executed by a web browser) that runs on mobile device690. Examples of mobile operating systems include Google Android, Apple iOS (I-Phone or iPad devices), Windows Mobile, Amazon Fire OS, RIM BlackBerry operating system, or the like.

It will be understood that the mobile device690is just one type of host computer in the magnetic coupler system600and that other arrangements may be utilized. Any of the data transmission or reception (e.g., exchange of user identifiers) functions described herein for the eyewear device100, mobile device690, and server system698can be embodied in on one or more methods as method steps or in one more applications as described previously. According to some embodiments, an “application,” “applications,” or “firmware” are program(s) that execute functions defined in the program, such as logic embodied in software or hardware instructions. Various programming languages can be employed to create one or more of the applications, structured in a variety of manners, such as object-oriented programming languages (e.g., Objective-C, Java, or C++) or procedural programming languages (e.g., C or assembly language). In a specific example, a third party application (e.g., an application developed using the ANDROID™ or IOS™ software development kit (SDK) by an entity other than the vendor of the particular platform) may be mobile software running on a mobile operating system such as IOS™, ANDROID™, WINDOWS® Phone, or another mobile operating systems. In this example, the third-party application can invoke API calls provided by the operating system to facilitate functionality described herein. The applications can be stored in any type of computer readable medium or computer storage device and be executed by one or more general-purpose computers. In addition, the methods and processes disclosed herein can alternatively be embodied in specialized computer hardware or an application specific integrated circuit (ASIC), field programmable gate array (FPGA) or a complex programmable logic device (CPLD).

Program aspects of the technology may be thought of as “products” or “articles of manufacture” typically in the form of executable code and/or associated data that is carried on or embodied in a type of machine-readable medium. For example, programming code could include code for the utilizing the magnetic coupler120, VHF radio transceiver241, and envelope detector242for transmission of data (e.g., user identifiers, audio, video, images) as well as the chat application650or other functions described herein. “Storage” type media include any or all of the tangible memory of the computers, processors or the like, or associated modules thereof, such as various semiconductor memories, tape drives, disk drives and the like, which may provide non-transitory storage at any time for the software programming. All or portions of the software may at times be communicated through the Internet or various other telecommunication networks. Such communications, for example, may enable loading of the software from one computer or processor into another, for example, from the server system698or host computer of the service provider into the computer platforms of the eyewear device100and mobile device690. Thus, another type of media that may bear the programming, media content or meta-data files includes optical, electrical and electromagnetic waves, such as used across physical interfaces between local devices, through wired and optical landline networks and over various air-links. The physical elements that carry such waves, such as wired or wireless links, optical links or the like, also may be considered as media bearing the software. As used herein, unless restricted to “non-transitory”, “tangible”, or “storage” media, terms such as computer or machine “readable medium” refer to any medium that participates in providing instructions or data to a processor for execution.

Hence, a machine-readable medium may take many forms of tangible storage medium. Non-volatile storage media include, for example, optical or magnetic disks, such as any of the storage devices in any computer(s) or the like, such as may be used to implement the client device, media gateway, transcoder, etc. shown in the drawings. Volatile storage media include dynamic memory, such as main memory of such a computer platform. Tangible transmission media include coaxial cables; copper wire and fiber optics, including the wires that comprise a bus within a computer system. Carrier-wave transmission media may take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media therefore include for example: a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any other optical medium, punch cards paper tape, any other physical storage medium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer may read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution.

While the foregoing has described what are considered to be the best mode and other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that they may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all modifications and variations that fall within the true scope of the present concepts.