Two wavelength MEMS scanning self-mixing interferometry for eye tracking

Abstract

Example devices include apparatus and methods relating to object tracking, object shape determination, and object distance measurements. Examples include eye tracker devices. In some examples, an optical scanner may direct a plurality of laser beams having different wavelengths over the surface of the eye as a combined beam. Laser beams may be provided by SMI (self-mixing interferometry) lasers. A beam combiner may be used to direct a combined laser beam to the optical scanner. Returned laser radiation re-enters the optical cavities of the SMI lasers, generating time-dependent variations of the amplitude and / or frequency of radiation within each optical cavity. Interference effects may vary based on the distance to the illuminated location on the object, such as an eye.

Description

TWO WAVELENGTH MEMS SCANNING SELF-MIXING INTERFEROMETRY FOR EYE TRACKING CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) of U.S. Provisional Application No. 63 / 605,668, filed December 4, 2023.FIELD

[0002] The present disclosure is directed to apparatus and methods relating to eye tracking and other distance measurement and imaging applications.BACKGROUND

[0003] Eye tracking devices may be used by different users under widely varying conditions and therefore incur problems with population coverage and performance under adverse conditions such as a strong ambient light environment.SUMMARY

[0004] According to a first aspect of the present disclosure there is provided a device comprising: a first light source; a second light source; a beam combiner; an optical scanner; and a controller, wherein: the first light source is a first self-mixing interferometry laser including a first optical cavity; the second light source is a second self-mixing interferometry laser including a second optical cavity; the beam combiner is configured to provide a combined light beam comprising a first light beam received from the first light source and a second light beam received from the second light source; the optical scanner is configured to receive the combined light beam and to scan the combined light beam over an object; returned light from the object is directed towards the first optical cavity and the second optical cavity; and the controller is configured to determine a distance to the object based on self-mixing interference signals received from the first light source and the second light source.

[0005] In some embodiments, the first light source may comprise a first laser diode configured to emit light having a first emission wavelength and the second light source may comprise a second laser diode configured to emit light having a second emission wavelength.

[0006] In some embodiments, the beam combiner may comprise a polarization beam combiner or a chromatic beam combiner.

[0007] In some embodiments, the optical scanner may comprise a MEMS scanning micromirror.

[0008] In some embodiments, a photodetector may be located within at least one of the first light source and the second light source.

[0009] In some embodiments, the first light source may have a first emission wavelength; the second light source may have a second emission wavelength; and the first emission wavelength and the second emission wavelength may differ by between 1 nm and 20 nm.

[0010] In some embodiments, the device may be sized and dimensioned to be incorporated into a wearable system.

[0011] According to a second aspect of the present disclosure there is provided a device comprising: a first light source comprising a first laser diode and a first optical cavity; a second light source comprising a second laser diode and a second optical cavity; a beam combiner; an optical scanner; and a controller, wherein: the beam combiner is configured to provide a combined light beam comprising a first light beam received from the first light source and a second light beam received from the second light source; the optical scanner is configured to receive the combined light beam and to scan the combined light beam over an object; returned light from the object is directed towards the first optical cavity and the second optical cavity; and the controller is configured to determine a distance to the object based on self-mixing interference signals received from the first light source and the second light source.

[0012] In some embodiments, the first light source may comprise a first selfmixing interferometry laser; and the second light source may comprise a second self-mixing interferometry laser.

[0013] In some embodiments, the first laser diode may be configured to emit light having a first emission wavelength; and the second laser diode may be configured to emit light having a second emission wavelength.

[0014] In some embodiments, the beam combiner may comprise a polarization beam combiner or a chromatic beam combiner.

[0015] In some embodiments, the optical scanner may comprise a MEMS scanning micromirror.

[0016] In some embodiments, the first light source may have a first emission wavelength; the second light source may have a second emission wavelength; and the first emission wavelength and the second emission wavelength may differ by between 1 nm and

[0017] In some embodiments, the device may be sized and dimensioned to be incorporated into a wearable system.

[0018] According to a third aspect of the present disclosure there is provided a method comprising: illuminating an object using first and second laser beams provided by first and second lasers and having an emission wavelength difference; detecting first and second self-mixing interferometry signals from the first and second lasers using light returned from the object to the first and second lasers; and determining a distance to the object using the first and second self-mixing interferometry signals.

[0019] In some embodiments, the first and second laser beams may be combined prior to illuminating the object.

[0020] In some embodiments, the first laser may comprise a first optical cavity and the second laser may comprise a second optical cavity.

[0021] In some embodiments, the second self-mixing interference signal from the second laser may be subtracted from the first self-mixing interference signal from the first laser.

[0022] In some embodiments, determining the distance to the object may comprise determining a frequency difference between the first and second self-mixing interferometry signals.

[0023] In some embodiments, determining the distance to the object may comprise determining a velocity difference between the first and second self-mixing interferometry signals.

[0024] It will be appreciated that any features described herein as being suitable for incorporation into one or more aspects or embodiments of the present disclosure are intended to be generalizable across any and all aspects and embodiments of the present disclosure. Other aspects of the present disclosure can be understood by those skilled in the art in light of the description, the claims, and the drawings of the present disclosure. The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claims.BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings illustrate a number of exemplary embodiments and are a part of the specification. Together with the following description,these drawings illustrate various examples of the present disclosure.

[0026] FIG. 1 is a schematic illustration of a device for two wavelength self-mixing interferometry (SMI) with MEMS scanning according to some embodiments.

[0027] FIG. 2 shows a simulated waveform for SMI intensity outputs according to some embodiments.

[0028] FIG. 3 shows a balanced detection and analog envelope-based phase detector according to some embodiments.

[0029] FIG. 4 illustrates the integration of an SMI photodetector proximate to a mirror of an optical cavity of a light source according to various embodiments.

[0030] FIG. 5 is an illustration of an example artificial-reality system according to some embodiments of this disclosure.

[0031] FIG. 6 is an illustration of an example artificial-reality system with a handheld device according to some embodiments of this disclosure.

[0032] FIG. 7A is an illustration of example user interactions within an artificialreality system according to some embodiments of this disclosure.

[0033] FIG. 7B is an illustration of example user interactions within an artificialreality system according to some embodiments of this disclosure.

[0034] FIG. 8A is an illustration of example user interactions within an artificialreality system according to some embodiments of this disclosure.

[0035] FIG. 8B is an illustration of example user interactions within an artificialreality system according to some embodiments of this disclosure.

[0036] FIG. 9 is an illustration of an example wrist-wearable device of an artificialreality system according to some embodiments of this disclosure.

[0037] FIG. 10 is an illustration of an example wearable artificial-reality system according to some embodiments of this disclosure.

[0038] FIG. 11 is an illustration of an example augmented-reality system according to some embodiments of this disclosure.

[0039] FIG. 12A is an illustration of an example virtual-reality system according to some embodiments of this disclosure.

[0040] FIG. 12B is an illustration of another perspective of the virtual-reality system shown in FIG. 12A according to some embodiments of this disclosure.

[0041] FIG. 13 is a block diagram showing system components of exampleartificial- and virtual-reality systems according to some embodiments of this disclosure.

[0042] FIG. 14 is an illustration of an example system that incorporates an eyetracking subsystem capable of tracking a user's eye(s) according to some embodiments of this disclosure.

[0043] FIG. 15 is a more detailed illustration of various aspects of the eye-tracking subsystem illustrated in FIG. 14 according to some embodiments of this disclosure.

[0044] Throughout the drawings, identical reference characters and descriptions may indicate similar, but not necessarily identical, elements. While the exemplary embodiments described herein are susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail herein. However, the exemplary embodiments described herein are not intended to be limited to the particular forms disclosed. Rather, the present disclosure covers all modifications, equivalents, and alternatives falling within this disclosure.DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0045] The present disclosure is directed to apparatus and methods relating to eye tracking and other distance measurement and imaging applications. In some examples, a device may provide eye tracking and / or eye imaging using self-mixing interference (SMI).

[0046] Eye tracking data may include pupil location, eye shape (e.g., cornea curvature), gaze direction, and other eye-related data. In some examples, a device may determine depth measurements to various locations on the eye and identify various regions of the eye (e.g., the pupil, cornea, iris, sclera and the like) and / or different regions proximate to the eye (e.g., surrounding skin, eyelids, and the like). An example device may be used by different users under widely varying conditions. For example, improved eye tracking may avoid problems with population coverage and performance under adverse conditions such as a strong ambient light environment.

[0047] Eye tracking may use a distance measurement approach to determine spatially varying distances between the device and locations over the eye surface. These distance measurements may also be termed depth measurements. In some examples, distance measurements may use self-mixing interferometry (SMI).

[0048] SMI is an interferometric technique in which a portion of the light emitted by a source is reflected by a moving object with a velocity component in the direction of the light beam into the source laser cavity causing a modulation both in amplitude and infrequency of the optical beam. That is, a portion of the light incident on an object (e.g., a body part such as the eye) is returned to an optical cavity of the light source where optical interference may occur between light within the cavity and the returned light (e.g., light reflected and / or scattered from the object). The returned light may modify the amplitude and / or frequency of the light beam emitted by the light source, for example, based on the relative phases of the emitted light beam and the returned light. The optical properties of the light source may be sensitive to the distance traveled by the returned beam (e.g., twice the distance to the object). Optical properties of the light source may be monitored by a photodetector in optical communication with the optical cavity and may be used to determine one or more of the following: distance to the object, object speed, object acceleration, and / or oscillatory properties of the object (e.g., vibrational properties such as the frequency and amplitude of object vibrations relative to an example device). In some examples, a device may include a distance, speed and / or vibration sensor based on SMI.

[0049] In some examples, object properties (e.g., distance, speed, acceleration, and / or oscillatory properties) may lead to a modulation in amplitude and in frequency of optical radiation within the optical cavity. In this context, the term optical radiation may refer to visible and / or IR radiation (e.g., near-IR radiation).

[0050] The light source may include a laser. The laser may be sensitive to the distance traveled by the reflected beam and may function as a distance, speed or vibration sensor. In some configurations, a photodetector (e.g., a photodiode) may be integrated with or supported by a light source to detect cavity radiation properties. That is, in some embodiments, a photodetector may be located inside a laser.

[0051] In certain embodiments, self-mixing interferometry (SMI) systems may operate without collimation optics or external photodiodes, which can reduce cost, weight, and system complexity. Provided that the return signal is sufficiently strong to achieve a signal-to-noise ratio greater than one, light expansion may be acceptable. This approach can lead to lower expenses and a simpler design while still providing effective measurement capabilities

[0052] Depth and / or velocity measurements enabled by SMI have been generally restricted to point based measurements using a single location on an object. Distance measurements (sometimes termed range or depth determination) may use frequency modulated continuous wave (FMCW) based approaches, using a frequency modulated laserfor chirped ranging. A device using an FMCW approach may provide high precision distance measurements, but frequency chirping (in which the frequency is ramped over a frequency range over a particular time duration) may significantly restrict the operation speed of the device.

[0053] For example, the light emission wavelength of a thermally tuned selfmixing interferometry laser diode (SMI-LD) may be tuned up to approximately 5 nm, but the modulation speed may be less than 50 kHz. A micro electromechanical system (MEMS)-tuned SMI-LD may be configured up to approximately 10 nm with a 500 kHz modulation speed. This may be suitable for sparse point detection-based eye tracking.

[0054] Eye tracking with camera-grade speed and resolution may require a faster laser modulation speed than those discussed above. For example, a greater quarter video graphic array (QVGA) resolution (320x240) with an imaging speed greater than 180 fps may require an SMI modulation speed of greater than approximately 10 MHz. This presents technological challenges and may not be practical for example devices. The depth resolution may be determined by the FFT (fast Fourier transform) bin size, and a high sampling rate (e.g., a rate greater than 1 kS or kilosamples per second) and may be arranged within one modulation period (e.g., approximately 100 ns). A higher modulation speed may put an extra and possibly unreasonable burden on the ADC electronics.

[0055] Examples systems include a multiple-wavelength interferometry based SMI approach that is compatible with MEMS scanning 3D imaging. In some examples, at least two different wavelengths may be used.

[0056] The following will provide, with reference to FIGS. 1-15, detailed descriptions of systems including eye tracking systems utilizing two wavelength MEMS scanning self-mixing interferometry (SMI). The discussion associated with FIGS. 1-4 includes a description of example SMI architectures and associated eye-tracking systems. The discussion associated with FIGS. 5-15 relates to exemplary virtual reality and augmented reality devices that may utilize self-mixing interferometry (SMI) based on two wavelength MEMS scanning.

[0057] FIG. 1 shows an example device architecture allowing two wavelength SMI interferometry with MEMS scanning. The device 100 of FIG. 1 includes two SMI laser diodes (SMI-LDs) denoted SMI1 (first laser diode) and SMI2 (second laser diode). First and second laser beams from the respective first and second SMI laser diodes are combined (e.g., using apolarization beam combiner or a chromatic beam combiner such as a dichroic beamsplitter or a diffraction grating). The combined beam is incident on an optical scanner, such as a MEMS-based scanning micromirror. The optical scanner projects the combined beam over a surface of an object (e.g., an eye) thus scanning it, and the incident combined beam results in a returned light beam incident on the respective SMI-LDs (e.g., the laser diode generating the respective wavelength of the combined beam). The two SMI-LDs may have two different light emission wavelengths (which may be denoted Xi and X2) and the returned light beam will generate self-interference within the respective SMI-LD.

[0058] As the combined beam is projected by the optical scanner, depth changes (e.g., changes in distance travelled by the light beams due to the surface profile of the illuminated object) may cause interferometric intensity changes for each SMI-LD, shown as li(t) and lz(t) in FIG. 1. Although this fluctuation over time may be fast for direct detection, a subtraction signal with a time varying amplitude and having a slower envelope may be readily detected.

[0059] The interferometric intensity from SMI may be determined using the following relationships.

[0060] The MEMS scan angle may be represented by:4(t) = AQsin(2nft + (p)

[0061] Where the MEMS scanning velocity is: v(t) = 2nfA0cos(2nft + cp

[0062] The maximum MEMS angular velocity during scanning is given by:^max 2jlfAQ.

[0063] In a particular example for a MEMS scanning half optical angle (Ao) of 30 degrees and a frequency, f, of 50 kHz for a Lissajous scanning mode, vmax~ 9.4 Mdeg / s (164,000 rad / s).

[0064] Within a reasonable sampling time (e.g., lOOMS / s10ns), there is a chance the scanning optical beam has travelled 9.4M ■ 10ns = 0.094 deg (5.64 arcmin or 1.64 mrad). Assuming a 20 mm eye relief distance, the optical beam has traveled approximately 33 microns. Assuming the depth change is on the same order as thetangential change, then the depth change is also 33 microns.

[0065] FIG. 2 shows a simulated waveform for SMI intensity outputs and the difference mode between them. The simulated waveform combines the requirements and assumptions discussed above. With XI, X2 each approximately 850 nm and XI - X2 ~ 2.5 nm (readily obtained using thermal tuning of an SMI-LD), then the difference mode between the two SMI waveforms has an equivalent wavelength of approximately 280 microns. Traveling through the waveform would take approximately 100 ns, and this time is sufficient for a desired sampling rate.

[0066] FIG. 3 shows a balanced detection and analog envelope detection based phase detector. Subtraction of the intensity of one signal from the other to obtain a difference signal requires high speed data analysis. FIG. 3 shows how balanced detection may be used to reject common mode signals and output only the difference between SMI1 and SMI2. The carrier frequency within the envelope output may be rectified and low pass filtered by an analog envelope detector before the output signal is further amplified and sampled by the analog-to-digital converter (ADC).

[0067] FIG. 4 illustrates in a simplified schematic that the SMI photodetector may be located proximate to a mirror of the optical cavity of a light source, which may be opposite the mirror through which the laser emits laser radiation.

[0068] In some examples, a device may include one or more light sources (e.g., SMI laser diodes) and an optical scanner. The light source, such as a laser, may direct a light beam towards the optical scanner, such as a MEMS (micro-electromechanical systems) based optical scanner. The optical scanner may be configured to scan the light beam overthe surface of an object, for example, a body part such as an eye. Returned light may re-enter the optical cavity of the laser. In this context, the term "returned light" may include specular or diffuse reflected light from the object and / or backscattered light from the object. The term returned light may refer to light returned to the optical cavity resulting from incidence of the laser beam on the object.

[0069] In some examples, different regions of the eye may be identified and / or differentiated using the optical properties of the detected light and / or the spatial variation of depth (e.g., from a surface profile of the eye). Example eye regions may include cornea, sclera, pupil, iris, cornea, conjunctiva, or other region within or proximate to the eye. In some examples, regions proximate to the eye may be detected and / or differentiated from eyeregions or other proximate eye regions. Regions proximate to the eye may include the eyelid or proximate skin regions. In some examples, scattered light from an exterior surface may be detected. In some examples, scattered light from an interior structure of the eye may be detected, such as light scattered by the lens, retina, and / or fovea.

[0070] SMI based measurements may enable improved determination of distances to (and the shape of) the eye and may be combined with one or more other eye tracking approaches.

[0071] In some examples, the device may include a wearable device and the object may be a portion of the body of a user such as a hand, wrist, arm, leg, foot, head, or portion thereof. In some examples, the device may include head-mounted device and the object may be the head of a user or a portion thereof, such as one or more eyes and optionally an eye region of the face (e.g., including an eye and surrounding regions such as the eyelid or surrounding skin).

[0072] Applications may include eye tracking. In some examples, the location of other body parts such as the fingers may be tracked. In some examples, approaches described herein may allow eye tracking, gaze direction determination, and determination of other user data.

[0073] Scanning based eye tracking allows a relatively fast scanning speed, dynamic laser intensity control, reduced size, reduced weight, and reduced power (e.g., relative to camera based systems). Laser SMI based systems may direct returned light to the laser cavity (e.g., including reflected and / or diffuse scattered light) and determine depth data for different regions of the eye.

[0074] In some examples, SMI scanning may include detecting scattered intensities for one or more polarizations of the light incident on the eye and / or scattered light from the eye. Polarizations may include linear polarizations of different orientations, circular polarizations of different handedness (e.g., right hand or left hand), or any suitable combination of polarization states.

[0075] Light returned from the eye may provide data relating the eye surface and environs. Eye imaging using SMI data may provide the spatial variation of one or more parameters of the eye, such as depth (e.g., distance to the eye surface from a reference point or reference plane), reflectivity, and the like. Returned light may include scattered and / or reflected light and may also be referred to as scattered or backscattered light.

[0076] In some examples, SMI-based imaging of the eye may be obtained using a scanning laser system. The laser beam may be steered in different directions (e.g., over an angular range) using an optical scanner. Returned light may be directed back to the optical cavity of the respective emitting laser

[0077] The improved depth determination using an SMI system allows improved differentiation of different regions of the eye, such as differentiation between one or more of the cornea, sclera, pupil, iris, eyelid or other region(s) within or proximate to the eye. In some examples, improved determination of the eye shape may be determined based on a plurality of depth measurements.

[0078] Examples include methods and apparatus for eye tracking and / or imaging using laser scanning. A device may include a light source (e.g., a laser), an optical scanner, and a detector. In some examples, a laser directs a laser beam towards an optical scanner (e.g., a MEMS-based optical scanner) configured to scan the light beam (e.g., a laser beam) over the eye surface. Returned light (e.g., scattered and / or reflected light) may be directed to an optical cavity of the light source and depth information determined using SMI.

[0079] In some examples, a device may detect periorbital region shape for a user (e.g., the skin configuration proximate to the eye(s)). The periorbital shape determined by methods such as those described herein may be used to generate improved avatar renditions in a VR environment. For example, a user's expression (e.g., smiling, frowning) and / or emotion (e.g., happy, sad) may be determined at least in part by a periorbital shape. In some examples, a person's expression may be correlated with periorbital shape using a training and / or calibration approach in which a user enters an indication of their expression and / or emotional state which may then be correlated with periorbital shape data. The expression of an avatar may then be generated in a manner more consistent with the expression and / or emotional state of the user.

[0080] In some examples, a device may include a controller, for example, control subsystem 1408 discussed in relation to FIG. 14 below. A controller may control the energizing of the laser, for example, for continuous wave or pulsed emission. A controller may receive sensor signals from a detector. A detector may include at least one photodetector in optical communication with the optical cavity of a respective SMI laser and / or at least one photodetector receiving a portion of the emitted and / or returned light from a respective SMI laser. The controller may determine an object distance based on the sensor signal. The sensorsignal may be processed, such as according to the description above in relation to FIG. 3. For example, a controller may include a signal processor receiving sensor signals from one or more SMI lasers and providing a difference signal.

[0081] Examples include methods and apparatus for eye tracking and determining eye shape. In some examples, a MEMS scanner directs two laser beams having different wavelengths over the surface of the eye. Both laser beams may illuminate similar portions of the eye concurrently. The laser beams may be provided by two SMI (self-mixing interferometry) lasers. A beam combiner / splitter may be used to direct the laser beams from the SMI lasers to the MEMS scanner. Laser radiation may be reflected or scattered back from the eye surface and re-enter the SMI lasers. Light intensities within the SMI laser cavities may be detected by optical detectors and may detect optical interference effects that vary based on the distance to the illuminated portion of the eye. First and second optical detectors associated with each SMI laser may be configured to provide first and second SMI signals, respectively. Subtracting the first SMI signal from the second SMI signal (and filtering out high frequency components) may provide a signal that conveys distance data and hence shape data related to the eye. The distance data may be obtained on a time scale (e.g., hundreds of nanoseconds) consistent with high-frequency MEMS scanning. Previous approaches using a single SMI laser and frequency chirping have been typically too slow to take advantage of high speed MEMS scanning approaches. Applications further include periorbital region shape detection.

[0082] An exemplary method includes illuminating an object using first and second laser beams provided by first and second lasers and having an emission wavelength difference, detecting first and second self-mixing interferometry signals from the first and second lasers using light returned from the object to the first and second lasers, and determining a distance to the object using the first and second self-mixing interferometry signals.

[0083] In some instantiations, the first laser includes a first optical cavity, the second laser includes a second optical cavity, and the light returned from the object is directed into the first optical cavity and into the second optical cavity.

[0084] E mbodiments of the present disclosure may include or be implemented in conjunction with various types of Artificial-Reality (AR) systems. AR may be any superimposed functionality and / or sensory-detectable content presented by an artificial-reality systemwithin a user's physical surroundings. In other words, AR is a form of reality that has been adjusted in some manner before presentation to a user. AR can include and / or represent virtual reality (VR), augmented reality, mixed AR (MAR), or some combination and / or variation of these types of realities. Similarly, AR environments may include VR environments (including non-immersive, semi-immersive, and fully immersive VR environments), augmented-reality environments (including marker-based augmented-reality environments, markerless augmented-reality environments, location-based augmented-reality environments, and projection-based augmented-reality environments), hybrid-reality environments, and / or any other type or form of mixed- or alternative-reality environments.

[0085] AR content may include completely computer-generated content or computer-generated content combined with captured (e.g., real-world) content. Such AR content may include video, audio, haptic feedback, or some combination thereof, any of which may be presented in a single channel or in multiple channels (such as stereo video that produces a three-dimensional (3D) effect to the viewer). Additionally, in some embodiments, AR may also be associated with applications, products, accessories, services, or some combination thereof, that are used to, for example, create content in an artificial reality and / or are otherwise used in (e.g., to perform activities in) an artificial reality.

[0086] AR systems may be implemented in a variety of different form factors and configurations. Some AR systems may be designed to work without near-eye displays (NEDs). Other AR systems may include a NED that also provides visibility into the real world (such as, e.g., VR system 1200 in FIGS. 12A and 12B). While some AR devices may be self-contained systems, other AR devices may communicate and / or coordinate with external devices to provide an AR experience to a user. Examples of such external devices include handheld controllers, mobile devices, desktop computers, devices worn by a user, devices worn by one or more other users, and / or any other suitable external system.

[0087] FIGS. 5-8B illustrate example artificial-reality (AR) systems in accordance with some embodiments. FIG. 5 shows a first AR system 500 and first example user interactions using a wrist-wearable device 502, a head-wearable device (e.g., AR system 1100), and / or a handheld intermediary processing device (HIPD) 506. FIG. 6 shows a second AR system 600 and second example user interactions using a wrist-wearable device 602, AR glasses 604, and / or an HIPD 606. FIGS. 7A and 7B show a third AR system 700 and third example user 708 interactions using a wrist-wearable device 702, a head-wearable device(e.g., VR headset 750), and / or an HIPD 706. FIGS. 8A and 8B show a fourth AR system 800 and fourth example user 808 interactions using a wrist-wearable device 830, VR headset 820, and / or a haptic device 860 (e.g., wearable gloves).

[0088] A wrist-wearable device 900, which can be used for wrist-wearable device 502, 602, 702, 830, and one or more of its components, are described below in reference to FIGS. 9 and 10; AR system 1100 and VR system 1200, which can respectively be used for AR glasses 504, 604 or VR headset 750, 820, and their one or more components are described below in reference to FIGS. 11-13.

[0089] Referring to FIG. 5, wrist-wearable device 502, AR glasses 504, and / or HIPD 506 can communicatively couple via a network 525 (e.g., cellular, near field, Wi-Fi, personal area network, wireless LAN, etc.). Additionally, wrist-wearable device 502, AR glasses 504, and / or HIPD 506 can also communicatively couple with one or more servers 530, computers 540 (e.g., laptops, computers, etc.), mobile devices 550 (e.g., smartphones, tablets, etc.), and / or other electronic devices via network 525 (e.g., cellular, near field, Wi-Fi, personal area network, wireless LAN, etc.).

[0090] In FIG. 5, a user 508 is shown wearing wrist-wearable device 502 and AR glasses 504 and having HIPD 506 on their desk. The wrist-wearable device 502, AR glasses 504, and HIPD 506 facilitate user interaction with an AR environment. In particular, as shown by first AR system 500, wrist-wearable device 502, AR glasses 504, and / or HIPD 506 cause presentation of one or more avatars 510, digital representations of contacts 512, and virtual objects 514. As discussed below, user 508 can interact with one or more avatars 510, digital representations of contacts 512, and virtual objects 514 via wrist-wearable device 502, AR glasses 504, and / or HIPD 506.

[0091] User 508 can use any of wrist-wearable device 502, AR glasses 504, and / or HIPD 506 to provide user inputs. For example, user 508 can perform one or more hand gestures that are detected by wrist-wearable device 502 (e.g., using one or more EMG sensors and / or IMUs, described below in reference to FIGS. 9 and 10) and / or AR glasses 504 (e.g., using one or more image sensor or camera) to provide a user input. Alternatively, or additionally, user 508 can provide a user input via one or more touch surfaces of wristwearable device 502, AR glasses 504, HIPD 506, and / or voice commands captured by a microphone of wrist-wearable device 502, AR glasses 504, and / or HIPD 506. In some embodiments, wrist-wearable device 502, AR glasses 504, and / or HIPD 506 include a digitalassistant to help user 508 in providing a user input (e.g., completing a sequence of operations, suggesting different operations or commands, providing reminders, confirming a command, etc.). In some embodiments, user 508 can provide a user input via one or more facial gestures and / orfacial expressions. For example, cameras of wrist-wearable device 502, AR glasses 504, and / or HIPD 506 can track eyes of user 508 for navigating a user interface.

[0092] Wrist-wearable device 502, AR glasses 504, and / or HIPD 506 can operate alone or in conjunction to allow user 508 to interact with the AR environment. In some embodiments, HIPD 506 is configured to operate as a central hub or control center for the wrist-wearable device 502, AR glasses 504, and / or another communicatively coupled device. For example, user 508 can provide an input to interact with the AR environment at any of wrist-wearable device 502, AR glasses 504, and / or HIPD 506, and HIPD 506 can identify one or more back-end and front-end tasks to cause the performance of the requested interaction and distribute instructions to cause the performance of the one or more back-end and frontend tasks at wrist-wearable device 502, AR glasses 504, and / or HIPD 506. In some embodiments, a back-end task is a background processing task that is not perceptible by the user (e.g., rendering content, decompression, compression, etc.), and a front-end task is a user-facing task that is perceptible to the user (e.g., presenting information to the user, providing feedback to the user, etc.). As described below, HIPD 506 can perform the back-end tasks and provide wrist-wearable device 502 and / or AR glasses 504 operational data corresponding to the performed back-end tasks such that wrist-wearable device 502 and / or AR glasses 504 can perform the front-end tasks. In this way, HIPD 506, which has more computational resources and greater thermal headroom than wrist-wearable device 502 and / or AR glasses 504, performs computationally intensive tasks and reduces the computer resource utilization and / or power usage of wrist-wearable device 502 and / or AR glasses 504.

[0093] In the example shown by first AR system 500, HIPD 506 identifies one or more back-end tasks and front-end tasks associated with a user request to initiate an AR video call with one or more other users (represented by avatar 510 and the digital representation of contact 512) and distributes instructions to cause the performance of the one or more back-end tasks and front-end tasks. In particular, HIPD 506 performs back-end tasks for processing and / or rendering image data (and other data) associated with the AR video call and provides operational data associated with the performed back-end tasks to AR glasses 504 such that the AR glasses 504 perform front-end tasks for presenting the AR video call(e.g., presenting avatar 510 and digital representation of contact 512).

[0094] In some embodiments, HIPD 506 can operate as a focal or anchor point for causing the presentation of information. This allows user 508 to be generally aware of where information is presented. For example, as shown in first AR system 500, avatar 510 and the digital representation of contact 512 are presented above HIPD 506. In particular, HIPD 506 and AR glasses 504 operate in conjunction to determine a location for presenting avatar 510 and the digital representation of contact 512. In some embodiments, information can be presented a predetermined distance from HIPD 506 (e.g., within 5 meters). For example, as shown in first AR system 500, virtual object 514 is presented on the desk some distance from HIPD 506. Similar to the above example, HIPD 506 and AR glasses 504 can operate in conjunction to determine a location for presenting virtual object 514. Alternatively, in some embodiments, presentation of information is not bound by HIPD 506. More specifically, avatar 510, digital representation of contact 512, and virtual object 514 do not have to be presented within a predetermined distance of HIPD 506.

[0095] User inputs provided at wrist-wearable device 502, AR glasses 504, and / or HIPD 506 are coordinated such that the user can use any device to initiate, continue, and / or complete an operation. For example, user 508 can provide a user input to AR glasses 504 to cause AR glasses 504 to present virtual object 514 and, while virtual object 514 is presented by AR glasses 504, user 508 can provide one or more hand gestures via wrist-wearable device 502 to interact and / or manipulate virtual object 514.

[0096] FIG. 6 shows a user 608 wearing a wrist-wearable device 602 and AR glasses 604, and holding an HIPD 606. In second AR system 600, the wrist-wearable device 602, AR glasses 604, and / or HIPD 606 are used to receive and / or provide one or more messages to a contact of user 608. In particular, wrist-wearable device 602, AR glasses 604, and / or HIPD 606 detect and coordinate one or more user inputs to initiate a messaging application and prepare a response to a received message via the messaging application.

[0097] In some embodiments, user 608 initiates, via a user input, an application on wrist-wearable device 602, AR glasses 604, and / or HIPD 606 that causes the application to initiate on at least one device. For example, in second AR system 600, user 608 performs a hand gesture associated with a command for initiating a messaging application (represented by messaging user interface 616), wrist-wearable device 602 detects the hand gesture and, based on a determination that user 608 is wearing AR glasses 604, causes AR glasses 604 topresent a messaging user interface 616 of the messaging application. AR glasses 604 can present messaging user interface 616 to user 608 via its display (e.g., as shown by a field of view 618 of user 608). In some embodiments, the application is initiated and executed on the device (e.g., wrist-wearable device 602, AR glasses 604, and / or HIPD 606) that detects the user input to initiate the application, and the device provides another device operational data to cause the presentation of the messaging application. For example, wrist-wearable device 602 can detect the user input to initiate a messaging application, initiate and run the messaging application, and provide operational data to AR glasses 604 and / or HIPD 606 to cause presentation of the messaging application. Alternatively, the application can be initiated and executed at a device other than the device that detected the user input. For example, wrist-wearable device 602 can detect the hand gesture associated with initiating the messaging application and cause HIPD 606 to run the messaging application and coordinate the presentation of the messaging application.

[0098] Further, user 608 can provide a user input provided at wrist-wearable device 602, AR glasses 604, and / or HIPD 606 to continue and / or complete an operation initiated at another device. For example, after initiating the messaging application via wristwearable device 602 and while AR glasses 604 present messaging user interface 616, user 608 can provide an input at HIPD 606 to prepare a response (e.g., shown by the swipe gesture performed on HIPD 606). Gestures performed by user 608 on HIPD 606 can be provided and / or displayed on another device. For example, a swipe gestured performed on HIPD 606 is displayed on a virtual keyboard of messaging user interface 616 displayed by AR glasses 604.

[0099] In some embodiments, wrist-wearable device 602, AR glasses 604, HIPD 606, and / or any other communicatively coupled device can present one or more notifications to user 608. The notification can be an indication of a new message, an incoming call, an application update, a status update, etc. User 608 can select the notification via wristwearable device 602, AR glasses 604, and / or HIPD 606 and can cause presentation of an application or operation associated with the notification on at least one device. For example, user 608 can receive a notification that a message was received at wrist-wearable device 602, AR glasses 604, HIPD 606, and / or any other communicatively coupled device and can then provide a user input at wrist-wearable device 602, AR glasses 604, and / or HIPD 606 to review the notification, and the device detecting the user input can cause an application associatedwith the notification to be initiated and / or presented at wrist-wearable device 602, AR glasses 604, and / or HI PD 606.

[0100] While the above example describes coordinated inputs used to interact with a messaging application, user inputs can be coordinated to interact with any number of applications including, but not limited to, gaming applications, social media applications, camera applications, web-based applications, financial applications, etc. For example, AR glasses 604 can present to user 608 game application data, and HIPD 606 can be used as a controller to provide inputs to the game. Similarly, user 608 can use wrist-wearable device 602 to initiate a camera of AR glasses 604, and user 308 can use wrist-wearable device 602, AR glasses 604, and / or HIPD 606 to manipulate the image capture (e.g., zoom in or out, apply filters, etc.) and capture image data.

[0101] u sers may interact with the devices disclosed herein in a variety of ways. For example, as shown in FIGS. 7A and 7B, a user 708 may interact with an AR system 700 by donning a VR headset 750 while holding HIPD 706 and wearing wrist-wearable device 702. In this example, AR system 700 may enable a user to interact with a game 710 by swiping their arm. One or more of VR headset 750, HIPD 706, and wrist-wearable device 702 may detect this gesture and, in response, may display a sword strike in game 710. Similarly, in FIGS. 8A and 8B, a user 808 may interact with an AR system 800 by donning a VR headset 820 while wearing haptic device 860 and wrist-wearable device 830. In this example, AR system 800 may enable a user to interact with a game 810 by swiping their arm. One or more of VR headset 820, haptic device 860, and wrist-wearable device 830 may detect this gesture and, in response, may display a spell being cast in game 710.

[0102] H aving discussed example AR systems, devices for interacting with such AR systems and other computing systems more generally will now be discussed in greater detail. Some explanations of devices and components that can be included in some or all of the example devices discussed below are explained herein for ease of reference. Certain types of the components described below may be more suitable for a particular set of devices, and less suitable for a different set of devices. But subsequent reference to the components explained here should be considered to be encompassed by the descriptions provided.

[0103] In some embodiments discussed below, example devices and systems, including electronic devices and systems, will be addressed. Such example devices and systems are not intended to be limiting, and one of skill in the art will understand thatalternative devices and systems to the example devices and systems described herein may be used to perform the operations and construct the systems and devices that are described herein.

[0104] An electronic device may be a device that uses electrical energy to perform a specific function. An electronic device can be any physical object that contains electronic components such as transistors, resistors, capacitors, diodes, and integrated circuits. Examples of electronic devices include smartphones, laptops, digital cameras, televisions, gaming consoles, and music players, as well as the example electronic devices discussed herein. As described herein, an intermediary electronic device may be a device that sits between two other electronic devices and / or a subset of components of one or more electronic devices and facilitates communication, data processing, and / or data transfer between the respective electronic devices and / or electronic components.

[0105] An integrated circuit may be an electronic device made up of multiple interconnected electronic components such as transistors, resistors, and capacitors. These components may be etched onto a small piece of semiconductor material, such as silicon. Integrated circuits may include analog integrated circuits, digital integrated circuits, mixed signal integrated circuits, and / or any other suitable type or form of integrated circuit. Examples of integrated circuits include application-specific integrated circuits (ASICs), processing units, central processing units (CPUs), co-processors, and accelerators.

[0106] Analog integrated circuits, such as sensors, power management circuits, and operational amplifiers, may process continuous signals and perform analog functions such as amplification, active filtering, demodulation, and mixing. Examples of analog integrated circuits include linear integrated circuits and radio frequency circuits.

[0107] Digital integrated circuits, which may be referred to as logic integrated circuits, may include microprocessors, microcontrollers, memory chips, interfaces, power management circuits, programmable devices, and / or any other suitable type or form of integrated circuit. In some embodiments, examples of integrated circuits include central processing units (CPUs),

[0108] Processing units, such as CPUs, may be electronic components that are responsible for executing instructions and controlling the operation of an electronic device (e.g., a computer). There are various types of processors that may be used interchangeably, or may be specifically required, by embodiments described herein. For example, a processormay be: (i) a general processor designed to perform a wide range of tasks, such as running software applications, managing operating systems, and performing arithmetic and logical operations; (ii) a microcontroller designed for specific tasks such as controlling electronic devices, sensors, and motors; (iii) an accelerator, such as a graphics processing unit (GPU), designed to accelerate the creation and rendering of images, videos, and animations (e.g., virtual-reality animations, such as three-dimensional modeling); (iv) a field-programmable gate array (FPGA) that can be programmed and reconfigured after manufacturing and / or can be customized to perform specific tasks, such as signal processing, cryptography, and machine learning; and / or (v) a digital signal processor (DSP) designed to perform mathematical operations on signals such as audio, video, and radio waves. One or more processors of one or more electronic devices may be used in various embodiments described herein.

[0109] Memory generally refers to electronic components in a computer or electronic device that store data and instructions for the processor to access and manipulate. Examples of memory can include: (i) random access memory (RAM) configured to store data and instructions temporarily; (ii) read-only memory (ROM) configured to store data and instructions permanently (e.g., one or more portions of system firmware, and / or boot loaders) and / or semi-permanently; (iii) flash memory, which can be configured to store data in electronic devices (e.g., USB drives, memory cards, and / or solid-state drives (SSDs)); and / or (iv) cache memory configured to temporarily store frequently accessed data and instructions. Memory, as described herein, can store structured data (e.g., SQL databases, MongoDB databases, GraphQL data, JSON data, etc.). Other examples of data stored in memory can include (i) profile data, including user account data, user settings, and / or other user data stored by the user, (ii) sensor data detected and / or otherwise obtained by one or more sensors, (iii) media content data including stored image data, audio data, documents, and the like, (iv) application data, which can include data collected and / or otherwise obtained and stored during use of an application, and / or any other types of data described herein.

[0110] Controllers may be electronic components that manage and coordinate the operation of other components within an electronic device (e.g., controlling inputs, processing data, and / or generating outputs). Examples of controllers can include: (i) microcontrollers, including small, low-power controllers that are commonly used in embedded systems and Internet of Things (loT) devices; (ii) programmable logic controllers (PLCs) that may be configured to be used in industrial automation systems to control andmonitor manufacturing processes; (iii) system-on-a-chip (SoC) controllers that integrate multiple components such as processors, memory, I / O interfaces, and other peripherals into a single chip; and / or (iv) DSPs.

[0111] A power system of an electronic device may be configured to convert incoming electrical power into a form that can be used to operate the device. A power system can include various components, such as (i) a power source, which can be an alternating current (AC) adapter or a direct current (DC) adapter power supply, (ii) a charger input, which can be configured to use a wired and / or wireless connection (which may be part of a peripheral interface, such as a USB, micro-USB interface, near-field magnetic coupling, magnetic inductive and magnetic resonance charging, and / or radio frequency (RF) charging), (iii) a power-management integrated circuit, configured to distribute power to various components of the device and to ensure that the device operates within safe limits (e.g., regulating voltage, controlling current flow, and / or managing heat dissipation), and / or (iv) a battery configured to store power to provide usable power to components of one or more electronic devices.

[0112] Peripheral interfaces may be electronic components (e.g., of electronic devices) that allow electronic devices to communicate with other devices or peripherals and can provide the ability to input and output data and signals. Examples of peripheral interfaces can include (i) universal serial bus (USB) and / or micro-USB interfaces configured for connecting devices to an electronic device, (ii) Bluetooth interfaces configured to allow devices to communicate with each other, including Bluetooth low energy (BLE), (iii) near field communication (NFC) interfaces configured to be short-range wireless interfaces for operations such as access control, (iv) POGO pins, which may be small, spring-loaded pins configured to provide a charging interface, (v) wireless charging interfaces, (vi) GPS interfaces, (vii) Wi-Fi interfaces for providing a connection between a device and a wireless network, and / or (viii) sensor interfaces.

[0113] Sensors may be electronic components (e.g., in and / or otherwise in electronic communication with electronic devices, such as wearable devices) configured to detect physical and environmental changes and generate electrical signals. Examples of sensors can include (i) imaging sensors for collecting imaging data (e.g., including one or more cameras disposed on a respective electronic device), (ii) biopotential-signal sensors, (iii) inertial measurement units (e.g., IMUs) for detecting, for example, angular rate, force,magnetic field, and / or changes in acceleration, (iv) heart rate sensors for measuring a user's heart rate, (v) SpO2 sensors for measuring blood oxygen saturation and / or other biometric data of a user, (vi) capacitive sensors for detecting changes in potential at a portion of a user's body (e.g., a sensor-skin interface), and / or (vii) light sensors (e.g., time-of -flight sensors, infrared light sensors, visible light sensors, etc.).

[0114] Bi opotential-signal-sensing components may be devices used to measure electrical activity within the body (e.g., biopotential-signal sensors). Some types of biopotential-signal sensors include (i) electroencephalography (EEG) sensors configured to measure electrical activity in the brain to diagnose neurological disorders, (ii) electrocardiography (ECG or EKG) sensors configured to measure electrical activity of the heart to diagnose heart problems, (iii) electromyography (EMG) sensors configured to measure the electrical activity of muscles and to diagnose neuromuscular disorders, and (iv) electrooculography (EOG) sensors configure to measure the electrical activity of eye muscles to detect eye movement and diagnose eye disorders.

[0115] An application stored in memory of an electronic device (e.g., software) may include instructions stored in the memory. Examples of such applications include (i) games, (ii) word processors, (iii) messaging applications, (iv) media-streaming applications, (v) financial applications, (vi) calendars, (vii) clocks, and (viii) communication interface modules for enabling wired and / or wireless connections between different respective electronic devices (e.g., IEEE 1102.15.4, Wi-Fi, ZigBee, 6L0WPAN, Thread, Z-Wave, Bluetooth Smart, ISAlOO.lla, WirelessHART, or MiWi), custom or standard wired protocols (e.g., Ethernet or HomePlug), and / or any other suitable communication protocols).

[0116] A communication interface may be a mechanism that enables different systems or devices to exchange information and data with each other, including hardware, software, or a combination of both hardware and software. For example, a communication interface can refer to a physical connector and / or port on a device that enables communication with other devices (e.g., USB, Ethernet, HDMI, Bluetooth). In some embodiments, a communication interface can refer to a software layer that enables different software programs to communicate with each other (e.g., application programming interfaces (APIs), protocols like HTTP and TCP / IP, etc.).

[0117] A graphics module may be a component or software module that is designed to handle graphical operations and / or processes and can include a hardwaremodule and / or a software module.

[0118] Non-transitory computer-readable storage media may be physical devices or storage media that can be used to store electronic data in a non-transitory form (e.g., such that the data is stored permanently until it is intentionally deleted or modified).

[0119] FIGS. 9 and 10 illustrate an example wrist-wearable device 900 and an example computer system 1000, in accordance with some embodiments. Wrist-wearable device 900 is an instance of wearable device 502 described in FIG. 5 herein, such that the wearable device 502 should be understood to have the features of the wrist-wearable device 900 and vice versa. FIG. 10 illustrates components of the wrist-wearable device 900, which can be used individually or in combination, including combinations that include other electronic devices and / or electronic components.

[0120] FIG. 9 shows a wearable band 910 and a watch body 920 (or capsule) being coupled, as discussed below, to form wrist-wearable device 900. Wrist-wearable device 900 can perform various functions and / or operations associated with navigating through user interfaces and selectively opening applications as well as the functions and / or operations described above with reference to FIGS. 5-8B.

[0121] As will be described in more detail below, operations executed by wristwearable device 900 can include (i) presenting content to a user (e.g., displaying visual content via a display 905), (ii) detecting (e.g., sensing) user input (e.g., sensing a touch on peripheral button 923 and / or at a touch screen of the display 905, a hand gesture detected by sensors (e.g., biopotential sensors)), (iii) sensing biometric data (e.g., neuromuscular signals, heart rate, temperature, sleep, etc.) via one or more sensors 913, messaging (e.g., text, speech, video, etc.); image capture via one or more imaging devices or cameras 925, wireless communications (e.g., cellular, near field, Wi-Fi, personal area network, etc.), location determination, financial transactions, providing haptic feedback, providing alarms, providing notifications, providing biometric authentication, providing health monitoring, providing sleep monitoring, etc.

[0122] The above-example functions can be executed independently in watch body 920, independently in wearable band 910, and / or via an electronic communication between watch body 920 and wearable band 910. In some embodiments, functions can be executed on wrist-wearable device 900 while an AR environment is being presented (e.g., via one of AR systems 500 to 800). The wearable devices described herein can also be used withother types of AR environments.

[0123] Wearable band 910 can be configured to be worn by a user such that an inner surface of a wearable structure 911 of wearable band 910 is in contact with the user's skin. In this example, when worn by a user, sensors 913 may contact the user's skin. In some examples, one or more of sensors 913 can sense biometric data such as a user's heart rate, a saturated oxygen level, temperature, sweat level, neuromuscular signals, or a combination thereof. One or more of sensors 913 can also sense data about a user's environment including a user's motion, altitude, location, orientation, gait, acceleration, position, or a combination thereof. In some embodiment, one or more of sensors 913 can be configured to track a position and / or motion of wearable band 910. One or more of sensors 913 can include any of the sensors defined above and / or discussed below with respect to FIG. 9.

[0124] One or more of sensors 913 can be distributed on an inside and / or an outside surface of wearable band 910. In some embodiments, one or more of sensors 913 are uniformly spaced along wearable band 910. Alternatively, in some embodiments, one or more of sensors 913 are positioned at distinct points along wearable band 910. As shown in FIG. 9, one or more of sensors 913 can be the same or distinct. For example, in some embodiments, one or more of sensors 913 can be shaped as a pill (e.g., sensor 913a), an oval, a circle a square, an oblong (e.g., sensor 913c) and / or any other shape that maintains contact with the user's skin (e.g., such that neuromuscular signal and / or other biometric data can be accurately measured at the user's skin). In some embodiments, one or more sensors of 913 are aligned to form pairs of sensors (e.g., for sensing neuromuscular signals based on differential sensing within each respective sensor). For example, sensor 913b may be aligned with an adjacent sensor to form sensor pair 914a and sensor 913d may be aligned with an adjacent sensor to form sensor pair 914b. In some embodiments, wearable band 910 does not have a sensor pair. Alternatively, in some embodiments, wearable band 910 has a predetermined number of sensor pairs (one pair of sensors, three pairs of sensors, four pairs of sensors, six pairs of sensors, sixteen pairs of sensors, etc.).

[0125] Wearable band 910 can include any suitable number of sensors 913. In some embodiments, the number and arrangement of sensors 913 depends on the particular application for which wearable band 910 is used. For instance, wearable band 910 can be configured as an armband, wristband, or chest-band that include a plurality of sensors 913 with different number of sensors 913, a variety of types of individual sensors with the pluralityof sensors 913, and different arrangements for each use case, such as medical use cases as compared to gaming or general day-to-day use cases.

[0126] In accordance with some embodiments, wearable band 910 further includes an electrical ground electrode and a shielding electrode. The electrical ground and shielding electrodes, like the sensors 913, can be distributed on the inside surface of the wearable band 910 such that they contact a portion of the user's skin. For example, the electrical ground and shielding electrodes can be at an inside surface of a coupling mechanism 916 or an inside surface of a wearable structure 911. The electrical ground and shielding electrodes can be formed and / or use the same components as sensors 913. In some embodiments, wearable band 910 includes more than one electrical ground electrode and more than one shielding electrode.

[0127] Sensors 913 can be formed as part of wearable structure 911 of wearable band 910. In some embodiments, sensors 913 are flush or substantially flush with wearable structure 911 such that they do not extend beyond the surface of wearable structure 911. While flush with wearable structure 911, sensors 913 are still configured to contact the user's skin (e.g., via a skin-contacting surface). Alternatively, in some embodiments, sensors 913 extend beyond wearable structure 911 a predetermined distance (e.g., 0.1 - 2 mm) to make contact and depress into the user's skin. In some embodiment, sensors 913 are coupled to an actuator (not shown) configured to adjust an extension height (e.g., a distance from the surface of wearable structure 911) of sensors 913 such that sensors 913 make contact and depress into the user's skin. In some embodiments, the actuators adjust the extension height between 0.01 mm - 1.2 mm. This may allow a user to customize the positioning of sensors 913 to improve the overall comfort of the wearable band 910 when worn while still allowing sensors 913 to contact the user's skin. In some embodiments, sensors 913 are indistinguishable from wearable structure 911 when worn by the user.

[0128] Wearable structure 911 can be formed of an elastic material, elastomers, etc., configured to be stretched and fitted to be worn by the user. In some embodiments, wearable structure 911 is a textile or woven fabric. As described above, sensors 913 can be formed as part of a wearable structure 911. For example, sensors 913 can be molded into the wearable structure 911, be integrated into a woven fabric (e.g., sensors 913 can be sewn into the fabric and mimic the pliability of fabric and can and / or be constructed from a series woven strands of fabric).

[0129] Wearable structure 911 can include flexible electronic connectors that interconnect sensors 913, the electronic circuitry, and / or other electronic components (described below in reference to FIG. 10) that are enclosed in wearable band 910. In some embodiments, the flexible electronic connectors are configured to interconnect sensors 913, the electronic circuitry, and / or other electronic components of wearable band 910 with respective sensors and / or other electronic components of another electronic device (e.g., watch body 920). The flexible electronic connectors are configured to move with wearable structure 911 such that the user adjustment to wearable structure 911 (e.g., resizing, pulling, folding, etc.) does not stress or strain the electrical coupling of components of wearable band 910.

[0130] As described above, wearable band 910 is configured to be worn by a user. In particular, wearable band 910 can be shaped or otherwise manipulated to be worn by a user. For example, wearable band 910 can be shaped to have a substantially circular shape such that it can be configured to be worn on the user's lower arm or wrist. Alternatively, wearable band 910 can be shaped to be worn on another body part of the user, such as the user's upper arm (e.g., around a bicep), forearm, chest, legs, etc. Wearable band 910 can include a retaining mechanism 912 (e.g., a buckle, a hook and loop fastener, etc.) for securing wearable band 910 to the user's wrist or other body part. While wearable band 910 is worn by the user, sensors 913 sense data (referred to as sensor data) from the user's skin. In some examples, sensors 913 of wearable band 910 obtain (e.g., sense and record) neuromuscular signals.

[0131] The sensed data (e.g., sensed neuromuscular signals) can be used to detect and / or determine the user's intention to perform certain motor actions. In some examples, sensors 913 may sense and record neuromuscular signals from the user as the user performs muscular activations (e.g., movements, gestures, etc.). The detected and / or determined motor actions (e.g., phalange (or digit) movements, wrist movements, hand movements, and / or other muscle intentions) can be used to determine control commands or control information (instructions to perform certain commands after the data is sensed) for causing a computing device to perform one or more input commands. For example, the sensed neuromuscular signals can be used to control certain user interfaces displayed on display 905 of wrist-wearable device 900 and / or can be transmitted to a device responsible for rendering an artificial-reality environment (e.g., a head-mounted display) to perform an action in anassociated artificial-reality environment, such as to control the motion of a virtual device displayed to the user. The muscular activations performed by the user can include static gestures, such as placing the user's hand palm down on a table, dynamic gestures, such as grasping a physical or virtual object, and covert gestures that are imperceptible to another person, such as slightly tensing a joint by co-contracting opposing muscles or using sub- muscular activations. The muscular activations performed by the user can include symbolic gestures (e.g., gestures mapped to other gestures, interactions, or commands, for example, based on a gesture vocabulary that specifies the mapping of gestures to commands).

[0132] The sensor data sensed by sensors 913 can be used to provide a user with an enhanced interaction with a physical object (e.g., devices communicatively coupled with wearable band 910) and / or a virtual object in an artificial-reality application generated by an artificial-reality system (e.g., user interface objects presented on the display 905, or another computing device (e.g., a smartphone)).

[0133] In some embodiments, wearable band 910 includes one or more haptic devices 1046 (e.g., a vibratory haptic actuator) that are configured to provide haptic feedback (e.g., a cutaneous and / or kinesthetic sensation, etc.) to the user's skin. Sensors 913 and / or haptic devices 1046 (shown in FIG. 10) can be configured to operate in conjunction with multiple applications including, without limitation, health monitoring, social media, games, and artificial reality (e.g., the applications associated with artificial reality).

[0134] Wearable band 910 can also include coupling mechanism 916 for detachably coupling a capsule (e.g., a computing unit) or watch body 920 (via a coupling surface of the watch body 920) to wearable band 910. For example, a cradle or a shape of coupling mechanism 916 can correspond to shape of watch body 920 of wrist-wearable device 900. In particular, coupling mechanism 916 can be configured to receive a coupling surface proximate to the bottom side of watch body 920 (e.g., a side opposite to a front side of watch body 920 where display 905 is located), such that a user can push watch body 920 downward into coupling mechanism 916 to attach watch body 920 to coupling mechanism 916. In some embodiments, coupling mechanism 916 can be configured to receive a top side of the watch body 920 (e.g., a side proximate to the front side of watch body 920 where display 905 is located) that is pushed upward into the cradle, as opposed to being pushed downward into coupling mechanism 916. In some embodiments, coupling mechanism 916 is an integrated component of wearable band 910 such that wearable band 910 and couplingmechanism 916 are a single unitary structure. In some embodiments, coupling mechanism 916 is a type of frame or shell that allows watch body 920 coupling surface to be retained within or on wearable band 910 coupling mechanism 916 (e.g., a cradle, a tracker band, a support base, a clasp, etc.).

[0135] Coupling mechanism 916 can allow for watch body 920 to be detachably coupled to the wearable band 910 through a friction fit, magnetic coupling, a rotation-based connector, a shear-pin coupler, a retention spring, one or more magnets, a clip, a pin shaft, a hook and loop fastener, or a combination thereof. A user can perform any type of motion to couple the watch body 920 to wearable band 910 and to decouple the watch body 920 from the wearable band 910. For example, a user can twist, slide, turn, push, pull, or rotate watch body 920 relative to wearable band 910, or a combination thereof, to attach watch body 920 to wearable band 910 and to detach watch body 920 from wearable band 910. Alternatively, as discussed below, in some embodiments, the watch body 920 can be decoupled from the wearable band 910 by actuation of a release mechanism 929.

[0136] Wearable band 910 can be coupled with watch body 920 to increase the functionality of wearable band 910 (e.g., converting wearable band 910 into wrist-wearable device 900, adding an additional computing unit and / or battery to increase computational resources and / or a battery life of wearable band 910, adding additional sensors to improve sensed data, etc.). As described above, wearable band 910 and coupling mechanism 916 are configured to operate independently (e.g., execute functions independently) from watch body 920. For example, coupling mechanism 916 can include one or more sensors 913 that contact a user's skin when wearable band 910 is worn by the user, with or without watch body 920 and can provide sensor data for determining control commands.

[0137] A user can detach watch body 920 from wearable band 910 to reduce the encumbrance of wrist-wearable device 900 to the user. For embodiments in which watch body 920 is removable, watch body 920 can be referred to as a removable structure, such that in these embodiments wrist-wearable device 900 includes a wearable portion (e.g., wearable band 910) and a removable structure (e.g., watch body 920).

[0138] Turning to watch body 920, in some examples watch body 920 can have a substantially rectangular or circular shape. Watch body 920 is configured to be worn by the user on their wrist or on another body part. More specifically, watch body 920 is sized to be easily carried by the user, attached on a portion of the user's clothing, and / or coupled towearable band 910 (forming the wrist-wearable device 900). As described above, watch body 920 can have a shape corresponding to coupling mechanism 916 of wearable band 910. In some embodiments, watch body 920 includes a single release mechanism 929 or multiple release mechanisms (e.g., two release mechanisms 929 positioned on opposing sides of watch body 920, such as spring-loaded buttons) for decoupling watch body 920 from wearable band 910. Release mechanism 929 can include, without limitation, a button, a knob, a plunger, a handle, a lever, a fastener, a clasp, a dial, a latch, or a combination thereof.

[0139] A user can actuate release mechanism 929 by pushing, turning, lifting, depressing, shifting, or performing other actions on release mechanism 929. Actuation of release mechanism 929 can release (e.g., decouple) watch body 920 from coupling mechanism 916 of wearable band 910, allowing the user to use watch body 920 independently from wearable band 910 and vice versa. For example, decoupling watch body 920 from wearable band 910 can allow a user to capture images using rear-facing camera 925b. Although release mechanism 929 is shown positioned at a corner of watch body 920, release mechanism 929 can be positioned anywhere on watch body 920 that is convenient for the user to actuate. In addition, in some embodiments, wearable band 910 can also include a respective release mechanism for decoupling watch body 920 from coupling mechanism 916. In some embodiments, release mechanism 929 is optional and watch body 920 can be decoupled from coupling mechanism 916 as described above (e.g., via twisting, rotating, etc.).

[0140] Watch body 920 can include one or more peripheral buttons 923 and 927 for performing various operations at watch body 920. For example, peripheral buttons 923 and 927 can be used to turn on or wake (e.g., transition from a sleep state to an active state) display 905, unlock watch body 920, increase or decrease a volume, increase or decrease a brightness, interact with one or more applications, interact with one or more user interfaces, etc. Additionally or alternatively, in some embodiments, display 905 operates as a touch screen and allows the userto provide one or more inputs for interacting with watch body 920.

[0141] In some embodiments, watch body 920 includes one or more sensors 921. Sensors 921 of watch body 920 can be the same or distinct from sensors 913 of wearable band 910. Sensors 921 of watch body 920 can be distributed on an inside and / or an outside surface of watch body 920. In some embodiments, sensors 921 are configured to contact a user's skin when watch body 920 is worn by the user. For example, sensors 921 can be placedon the bottom side of watch body 920 and coupling mechanism 916 can be a cradle with an opening that allows the bottom side of watch body 920 to directly contact the user's skin. Alternatively, in some embodiments, watch body 920 does not include sensors that are configured to contact the user's skin (e.g., including sensors internal and / or external to the watch body 920 that are configured to sense data of watch body 920 and the surrounding environment). In some embodiments, sensors 921 are configured to track a position and / or motion of watch body 920.

[0142] Watch body 920 and wearable band 910 can share data using a wired communication method (e.g., a Universal Asynchronous Receiver / Transmitter (UART), a USB transceiver, etc.) and / or a wireless communication method (e.g., near field communication, Bluetooth, etc.). For example, watch body 920 and wearable band 910 can share data sensed by sensors 913 and 921, as well as application and device specific information (e.g., active and / or available applications, output devices (e.g., displays, speakers, etc.), input devices (e.g., touch screens, microphones, imaging sensors, etc.).

[0143] In some embodiments, watch body 920 can include, without limitation, a front-facing camera 925a and / or a rear-facing camera 925b, sensors 921 (e.g., a biometric sensor, an IMU, a heart rate sensor, a saturated oxygen sensor, a neuromuscular signal sensor, an altimeter sensor, a temperature sensor, a bioimpedance sensor, a pedometer sensor, an optical sensor (e.g., imaging sensor 1063), a touch sensor, a sweat sensor, etc.). In some embodiments, watch body 920 can include one or more haptic devices 1076 (e.g., a vibratory haptic actuator) that is configured to provide haptic feedback (e.g., a cutaneous and / or kinesthetic sensation, etc.) to the user. Sensors 1021 and / or haptic device 1076 can also be configured to operate in conjunction with multiple applications including, without limitation, health monitoring applications, social media applications, game applications, and artificial reality applications (e.g., the applications associated with artificial reality).

[0144] As described above, watch body 920 and wearable band 910, when coupled, can form wrist-wearable device 900. When coupled, watch body 920 and wearable band 910 may operate as a single device to execute functions (operations, detections, communications, etc.) described herein. In some embodiments, each device may be provided with particular instructions for performing the one or more operations of wrist-wearable device 900. For example, in accordance with a determination that watch body 920 does not include neuromuscular signal sensors, wearable band 910 can include alternative instructionsfor performing associated instructions (e.g., providing sensed neuromuscular signal data to watch body 920 via a different electronic device). Operations of wrist-wearable device 900 can be performed by watch body 920 alone or in conjunction with wearable band 910 (e.g., via respective processors and / or hardware components) and vice versa. In some embodiments, operations of wrist-wearable device 900, watch body 920, and / or wearable band 910 can be performed in conjunction with one or more processors and / or hardware components.

[0145] As described below with reference to the block diagram of FIG. 10, wearable band 910 and / or watch body 920 can each include independent resources required to independently execute functions. For example, wearable band 910 and / or watch body 920 can each include a power source (e.g., a battery), a memory, data storage, a processor (e.g., a central processing unit (CPU)), communications, a light source, and / or input / output devices.

[0146] FIG. 10 shows block diagrams of a computing system 1030 corresponding to wearable band 910 and a computing system 1060 corresponding to watch body 920 according to some embodiments. Computing system 1000 of wrist-wearable device 900 may include a combination of components of wearable band computing system 1030 and watch body computing system 1060, in accordance with some embodiments.

[0147] Watch body 920 and / or wearable band 910 can include one or more components shown in watch body computing system 1060. In some embodiments, a single integrated circuit may include all or a substantial portion of the components of watch body computing system 1060 included in a single integrated circuit. Alternatively, in some embodiments, components of the watch body computing system 1060 may be included in a plurality of integrated circuits that are communicatively coupled. In some embodiments, watch body computing system 1060 may be configured to couple (e.g., via a wired or wireless connection) with wearable band computing system 1030, which may allow the computing systems to share components, distribute tasks, and / or perform other operations described herein (individually or as a single device).

[0148] Watch body computing system 1060 can include one or more processors 1079, a controller 1077, a peripherals interface 1061, a power system 1095, and memory (e.g., a memory 1080).

[0149] Power system 1095 can include a charger input 1096, a powermanagement integrated circuit (PMIC) 1097, and a battery 1098. In some embodiments, awatch body 920 and a wearable band 910 can have respective batteries (e.g., battery 1098 and 1059) and can share power with each other. Watch body 920 and wearable band 910 can receive a charge using a variety of techniques. In some embodiments, watch body 920 and wearable band 910 can use a wired charging assembly (e.g., power cords) to receive the charge. Alternatively, or in addition, watch body 920 and / or wearable band 910 can be configured for wireless charging. For example, a portable charging device can be designed to mate with a portion of watch body 920 and / or wearable band 910 and wirelessly deliver usable power to battery 1098 of watch body 920 and / or battery 1059 of wearable band 910. Watch body 920 and wearable band 910 can have independent power systems (e.g., power system 1095 and 1056, respectively) to enable each to operate independently. Watch body 920 and wearable band 910 can also share power (e.g., one can charge the other) via respective PMICs (e.g., PMICs 1097 and 1058) and charger inputs (e.g., 1057 and 1096) that can share power over power and ground conductors and / or over wireless charging antennas.

[0150] In some embodiments, peripherals interface 1061 can include one or more sensors 1021. Sensors 1021 can include one or more coupling sensors 1062 for detecting when watch body 920 is coupled with another electronic device (e.g., a wearable band 910). Sensors 1021 can include one or more imaging sensors 1063 (e.g., one or more of cameras 1025, and / or separate imaging sensors 1063 (e.g., thermal-imaging sensors)). In some embodiments, sensors 1021 can include one or more SpO2 sensors 1064. In some embodiments, sensors 1021 can include one or more biopotential-signal sensors (e.g., EMG sensors 1065, which may be disposed on an interior, user-facing portion of watch body 920 and / or wearable band 910). In some embodiments, sensors 1021 may include one or more capacitive sensors 1066. In some embodiments, sensors 1021 may include one or more heart rate sensors 1067. In some embodiments, sensors 1021 may include one or more IMU sensors 1068. In some embodiments, one or more IMU sensors 1068 can be configured to detect movement of a user's hand or other location where watch body 920 is placed or held.

[0151] In some embodiments, one or more of sensors 1021 may provide an example human-machine interface. For example, a set of neuromuscular sensors, such as EMG sensors 1065, may be arranged circumferentially around wearable band 910 with an interior surface of EMG sensors 1065 being configured to contact a user's skin. Any suitable number of neuromuscular sensors may be used (e.g., between 2 and 20 sensors). The number and arrangement of neuromuscular sensors may depend on the particular application forwhich the wearable device is used. For example, wearable band 910 can be used to generate control information for controlling an augmented reality system, a robot, controlling a vehicle, scrolling through text, controlling a virtual avatar, or any other suitable control task.

[0152] In some embodiments, neuromuscular sensors may be coupled together using flexible electronics incorporated into the wireless device, and the output of one or more of the sensing components can be optionally processed using hardware signal processing circuitry (e.g., to perform amplification, filtering, and / or rectification). In other embodiments, at least some signal processing of the output of the sensing components can be performed in software such as processors 1079. Thus, signal processing of signals sampled by the sensors can be performed in hardware, software, or by any suitable combination of hardware and software, as aspects of the technology described herein are not limited in this respect.

[0153] N euromuscular signals may be processed in a variety of ways. For example, the output of EMG sensors 1065 may be provided to an analog front end, which may be configured to perform analog processing (e.g., amplification, noise reduction, filtering, etc.) on the recorded signals. The processed analog signals may then be provided to an analog-to- digital converter, which may convert the analog signals to digital signals that can be processed by one or more computer processors. Furthermore, although this example is as discussed in the context of interfaces with EMG sensors, the embodiments described herein can also be implemented in wearable interfaces with other types of sensors including, but not limited to, mechanomyography (MMG) sensors, sonomyography (SMG) sensors, and electrical impedance tomography (EIT) sensors.

[0154] In some embodiments, peripherals interface 1061 includes a near-field communication (NFC) component 1069, a global-position system (GPS) component 1070, a long-term evolution (LTE) component 1071, and / or a Wi-Fi and / or Bluetooth communication component 1072. In some embodiments, peripherals interface 1061 includes one or more buttons 1073 (e.g., peripheral buttons 923 and 927 in FIG. 9), which, when selected by a user, cause operation to be performed at watch body 920. In some embodiments, the peripherals interface 1061 includes one or more indicators, such as a light emitting diode (LED), to provide a user with visual indicators (e.g., message received, low battery, active microphone and / or camera, etc.).

[0155] Watch body 920 can include at least one display 905 for displaying visual representations of information or data to a user, including user-interface elements and / orthree-dimensional virtual objects. The display can also include a touch screen for inputting user inputs, such as touch gestures, swipe gestures, and the like. Watch body 920 can include at least one speaker 1074 and at least one microphone 1075 for providing audio signals to the user and receiving audio input from the user. The user can provide user inputs through microphone 1075 and can also receive audio output from speaker 1074 as part of a haptic event provided by haptic controller 1078. Watch body 920 can include at least one camera 1025, including a front camera 1025a and a rear camera 1025b. Cameras 1025 can include ultra-wide-angle cameras, wide angle cameras, fish-eye cameras, spherical cameras, telephoto cameras, depth-sensing cameras, or other types of cameras.

[0156] Watch body computing system 1060 can include one or more haptic controllers 1078 and associated componentry (e.g., haptic devices 1076) for providing haptic events at watch body 920 (e.g., a vibrating sensation or audio output in response to an event at the watch body 920). Haptic controllers 1078 can communicate with one or more haptic devices 1076, such as electroacoustic devices, including a speaker of the one or more speakers 1074 and / or other audio components and / or electromechanical devices that convert energy into linear motion such as a motor, solenoid, electroactive polymer, piezoelectric actuator, electrostatic actuator, or other tactile output generating components (e.g., a component that converts electrical signals into tactile outputs on the device). Haptic controller 1078 can provide haptic events to that are capable of being sensed by a user of watch body 920. In some embodiments, one or more haptic controllers 1078 can receive input signals from an application of applications 1082.

[0157] In some embodiments, wearable band computing system 1030 and / or watch body computing system 1060 can include memory 1080, which can be controlled by one or more memory controllers of controllers 1077. In some embodiments, software components stored in memory 1080 include one or more applications 1082 configured to perform operations at the watch body 920. In some embodiments, one or more applications 1082 may include games, word processors, messaging applications, calling applications, web browsers, social media applications, media streaming applications, financial applications, calendars, clocks, etc. In some embodiments, software components stored in memory 1080 include one or more communication interface modules 1083 as defined above. In some embodiments, software components stored in memory 1080 include one or more graphics modules 1084 for rendering, encoding, and / or decoding audio and / or visual data and one ormore data management modules 1085 for collecting, organizing, and / or providing access to data 1087 stored in memory 1080. In some embodiments, one or more of applications 1082 and / or one or more modules can work in conjunction with one another to perform various tasks at the watch body 920.

[0158] In some embodiments, software components stored in memory 1080 can include one or more operating systems 1081 (e.g., a Linux-based operating system, an Android operating system, etc.). Memory 1080 can also include data 1087. Data 1087 can include profile data 1088A, sensor data 1089A, media content data 1090, and application data 1091.

[0159] It should be appreciated that watch body computing system 1060 is an example of a computing system within watch body 920, and that watch body 920 can have more or fewer components than shown in watch body computing system 1060, can combine two or more components, and / or can have a different configuration and / or arrangement of the components. The various components shown in watch body computing system 1060 are implemented in hardware, software, firmware, or a combination thereof, including one or more signal processing and / or application-specific integrated circuits.

[0160] Turning to the wearable band computing system 1030, one or more components that can be included in wearable band 910 are shown. Wearable band computing system 1030 can include more or fewer components than shown in watch body computing system 1060, can combine two or more components, and / or can have a different configuration and / or arrangement of some or all of the components. In some embodiments, all, or a substantial portion of the components of wearable band computing system 1030 are included in a single integrated circuit. Alternatively, in some embodiments, components of wearable band computing system 1030 are included in a plurality of integrated circuits that are communicatively coupled. As described above, in some embodiments, wearable band computing system 1030 is configured to couple (e.g., via a wired or wireless connection) with watch body computing system 1060, which allows the computing systems to share components, distribute tasks, and / or perform other operations described herein (individually or as a single device).

[0161] Wearable band computing system 1030, similar to watch body computing system 1060, can include one or more processors 1049, one or more controllers 1047 (including one or more haptics controllers 1048), a peripherals interface 1031 that canincludes one or more sensors 1013 and other peripheral devices, a power source (e.g., a power system 1056), and memory (e.g., a memory 1050) that includes an operating system (e.g., an operating system 1051), data (e.g., data 1054 including profile data 1088B, sensor data 1089B, etc.), and one or more modules (e.g., a communications interface module 1052, a data management module 1053, etc.).

[0162] One or more of sensors 1013 can be analogous to sensors 1021 of watch body computing system 1060. For example, sensors 1013 can include one or more coupling sensors 1032, one or more SpO2 sensors 1034, one or more EMG sensors 1035, one or more capacitive sensors 1036, one or more heart rate sensors 1037, and one or more IMU sensors 1038.

[0163] Peripherals interface 1031 can also include other components analogous to those included in peripherals interface 1061 of watch body computing system 1060, including an NFC component 1039, a GPS component 1040, an LTE component 1041, a Wi-Fi and / or Bluetooth communication component 1042, and / or one or more haptic devices 1046 as described above in reference to peripherals interface 1061. In some embodiments, peripherals interface 1031 includes one or more buttons 1043, a display 1033, a speaker 1044, a microphone 1045, and a camera 1055. In some embodiments, peripherals interface 1031 includes one or more indicators, such as an LED.

[0164] It should be appreciated that wearable band computing system 1030 is an example of a computing system within wearable band 910, and that wearable band 910 can have more or fewer components than shown in wearable band computing system 1030, combine two or more components, and / or have a different configuration and / or arrangement of the components. The various components shown in wearable band computing system 1030 can be implemented in one or more of a combination of hardware, software, or firmware, including one or more signal processing and / or application-specific integrated circuits.

[0165] Wrist-wearable device 900 with respect to FIG. 9 is an example of wearable band 910 and watch body 920 coupled together, so wrist-wearable device 900 will be understood to include the components shown and described for wearable band computing system 1030 and watch body computing system 1060. In some embodiments, wrist-wearable device 900 has a split architecture (e.g., a split mechanical architecture, a split electrical architecture, etc.) between watch body 920 and wearable band 910. In other words, all of thecomponents shown in wearable band computing system 1030 and watch body computing system 1060 can be housed or otherwise disposed in a combined wrist-wearable device 900 or within individual components of watch body 920, wearable band 910, and / or portions thereof (e.g., a coupling mechanism 916 of wearable band 910).

[0166] The techniques described above can be used with any device for sensing neuromuscular signals but could also be used with other types of wearable devices for sensing neuromuscular signals (such as body-wearable or head-wearable devices that might have neuromuscular sensors closer to the brain or spinal column).

[0167] In some embodiments, wrist-wearable device 900 can be used in conjunction with a head-wearable device (e.g., AR system 1100 and VR system 1200) and / or an HIPD described below, and wrist-wearable device 900 can also be configured to be used to allow a userto control any aspect of the artificial reality (e.g., by using EMG-based gestures to control user interface objects in the artificial reality and / or by allowing a user to interact with the touchscreen on the wrist-wearable device to also control aspects of the artificial reality). Having thus described example wrist-wearable devices, attention will now be turned to example head-wearable devices, such AR system 1100 and VR system 1200.

[0168] FIGS. 11 to 13 show example artificial-reality systems, which can be used as or in connection with wrist-wearable device 900. In some embodiments, AR system 1100 includes an eyewear device 1102, as shown in FIG. 11. In some embodiments, VR system 1200 includes a head-mounted display (HMD) 1212, as shown in FIGS. 12A and 12B. In some embodiments, AR system 1100 and VR system 1200 can include one or more analogous components (e.g., components for presenting interactive artificial-reality environments, such as processors, memory, and / or presentation devices, including one or more displays and / or one or more waveguides), some of which are described in more detail with respect to FIG. 13. As described herein, a head-wearable device can include components of eyewear device 1102 and / or head-mounted display 1212. Some embodiments of head-wearable devices do not include any displays, including any of the displays described with respect to AR system 1100 and / or VR system 1200. While the example artificial-reality systems are respectively described herein as AR system 1100 and VR system 1200, either or both of the example AR systems described herein can be configured to present fully-immersive virtual-reality scenes presented in substantially all of a user's field of view or subtler augmented-reality scenes that are presented within a portion, less than all, of the user's field of view.

[0169] FIG. 11 show an example visual depiction of AR system 1100, including an eyewear device 1102 (which may also be described herein as augmented-reality glasses, and / or smart glasses). AR system 1100 can include additional electronic components that are not shown in FIG. 11, such as a wearable accessory device and / or an intermediary processing device, in electronic communication or otherwise configured to be used in conjunction with the eyewear device 1102. In some embodiments, the wearable accessory device and / or the intermediary processing device may be configured to couple with eyewear device 1102 via a coupling mechanism in electronic communication with a coupling sensor 1324 (FIG. 13), where coupling sensor 1324 can detect when an electronic device becomes physically or electronically coupled with eyewear device 1102. In some embodiments, eyewear device 1102 can be configured to couple to a housing 1390 (FIG. 13), which may include one or more additional coupling mechanisms configured to couple with additional accessory devices. The components shown in FIG. 11 can be implemented in hardware, software, firmware, or a combination thereof, including one or more signal-processing components and / or application-specific integrated circuits (ASICs).

[0170] Eyewear device 1102 includes mechanical glasses components, including a frame 1104 configured to hold one or more lenses (e.g., one or both lenses 1106-1 and 1106- 2). One of ordinary skill in the art will appreciate that eyewear device 1102 can include additional mechanical components, such as hinges configured to allow portions of frame 1104 of eyewear device 1102 to be folded and unfolded, a bridge configured to span the gap between lenses 1106-1 and 1106-2 and rest on the user's nose, nose pads configured to rest on the bridge of the nose and provide support for eyewear device 1102, earpieces configured to rest on the user's ears and provide additional support for eyewear device 1102, temple arms configured to extend from the hinges to the earpieces of eyewear device 1102, and the like. One of ordinary skill in the art will further appreciate that some examples of AR system 1100 can include none of the mechanical components described herein. For example, smart contact lenses configured to present artificial reality to users may not include any components of eyewear device 1102.

[0171] Eyewear device 1102 includes electronic components, many of which will be described in more detail below with respect to FIG. 13. Some example electronic components are illustrated in FIG. 11, including acoustic sensors 1125-1, 1125-2, 1125-3, 1125-4, 1125-5, and 1125-6, which can be distributed along a substantial portion of the frame1104 of eyewear device 1102. Eyewear device 1102 also includes a left camera 1139A and a right camera 1139B, which are located on different sides of the frame 1104. Eyewear device 1102 also includes a processor 1148 (or any other suitable type or form of integrated circuit) that is embedded into a portion of the frame 1104.

[0172] FIGS. 12A and 12B show a VR system 1200 that includes a head-mounted display (HMD) 1212 (e.g., also referred to herein as an artificial-reality headset, a headwearable device, a VR headset, etc.), in accordance with some embodiments. As noted, some artificial-reality systems (e.g., AR system 1100) may, instead of blending an artificial reality with actual reality, substantially replace one or more of a user's visual and / or other sensory perceptions of the real world with a virtual experience (e.g., AR systems 700 and 800).

[0173] HMD 1212 includes a front body 1214 and a frame 1216 (e.g., a strap or band) shaped to fit around a user's head. In some embodiments, front body 1214 and / or frame 1216 include one or more electronic elements for facilitating presentation of and / or interactions with an AR and / or VR system (e.g., displays, IMUs, tracking emitter or detectors). In some embodiments, HMD 1212 includes output audio transducers (e.g., an audio transducer 1218), as shown in FIG. 12B. In some embodiments, one or more components, such as the output audio transducer(s) 1218 and frame 1216, can be configured to attach and detach (e.g., are detachably attachable) to HMD 1212 (e.g., a portion or all of frame 1216, and / or audio transducer 1218), as shown in FIG. 12B. In some embodiments, coupling a detachable component to HMD 1212 causes the detachable component to come into electronic communication with HMD 1212.

[0174] FIGS. 12A and 12B also show that VR system 1200 includes one or more cameras, such as left camera 1239A and right camera 1239B, which can be analogous to left and right cameras 1139A and 1139B on frame 1104 of eyewear device 1102. In some embodiments, VR system 1200 includes one or more additional cameras (e.g., cameras 1239C and 1239D), which can be configured to augment image data obtained by left and right cameras 1239A and 1239B by providing more information. For example, camera 1239C can be used to supply color information that is not discerned by cameras 1239A and 1239B. In some embodiments, one or more of cameras 1239A to 1239D can include an optional IR cut filter configured to remove IR light from being received at the respective camera sensors.

[0175] FIG. 13 illustrates a computing system 1320 and an optional housing 1390, each of which show components that can be included in AR system 1100 and / or VR system1200. In some embodiments, more or fewer components can be included in optional housing 1390 depending on practical restraints of the respective AR system being described.

[0176] In some embodiments, computing system 1320 can include one or more peripherals interfaces 1322A and / or optional housing 1390 can include one or more peripherals interfaces 1322B. Each of computing system 1320 and optional housing 1390 can also include one or more power systems 1342A and 1342B, one or more controllers 1346 (including one or more haptic controllers 1347), one or more processors 1348A and 1348B (as defined above, including any of the examples provided), and memory 1350A and 1350B, which can all be in electronic communication with each other. For example, the one or more processors 1348A and 1348B can be configured to execute instructions stored in memory 1350A and 1350B, which can cause a controller of one or more of controllers 1346 to cause operations to be performed at one or more peripheral devices connected to peripherals interface 1322A and / or 1322B. In some embodiments, each operation described can be powered by electrical power provided by power system 1342A and / or 1342B.

[0177] In some embodiments, peripherals interface 1322A can include one or more devices configured to be part of computing system 1320, some of which have been defined above and / or described with respect to the wrist-wearable devices shown in FIGS. 9 and 10. For example, peripherals interface 1322A can include one or more sensors 1323A. Some example sensors 1323A include one or more coupling sensors 1324, one or more acoustic sensors 1325, one or more imaging sensors 1326, one or more EMG sensors 1327, one or more capacitive sensors 1328, one or more IMU sensors 1329, and / or any other types of sensors explained above or described with respect to any other embodiments discussed herein.

[0178] In some embodiments, peripherals interfaces 1322A and 1322B can include one or more additional peripheral devices, including one or more NFC devices 1330, one or more GPS devices 1331, one or more LTE devices 1332, one or more Wi-Fi and / or Bluetooth devices 1333, one or more buttons 1334 (e.g., including buttons that are slidable or otherwise adjustable), one or more displays 1335A and 1335B, one or more speakers 1336A and 1336B, one or more microphones 1337, one or more cameras 1338A and 1338B (e.g., including the left camera 1339A and / or a right camera 1339B), one or more haptic devices 1340, and / or any other types of peripheral devices defined above or described with respect to any other embodiments discussed herein.

[0179] AR systems can include a variety of types of visual feedback mechanisms (e.g., presentation devices). For example, display devices in AR system 1100 and / or VR system 1200 can include one or more liquid-crystal displays (LCDs), light emitting diode (LED) displays, organic LED (OLED) displays, and / or any other suitable types of display screens. Artificialreality systems can include a single display screen (e.g., configured to be seen by both eyes), and / or can provide separate display screens for each eye, which can allow for additional flexibility for varifocal adjustments and / or for correcting a refractive error associated with a user's vision. Some embodiments of AR systems also include optical subsystems having one or more lenses (e.g., conventional concave or convex lenses, Fresnel lenses, or adjustable liquid lenses) through which a user can view a display screen.

[0180] For example, respective displays 1335A and 1335B can be coupled to each of the lenses 1106-1 and 1106-2 of AR system 1100. Displays 1335A and 1335B may be coupled to each of lenses 1106-1 and 1106-2, which can act together or independently to present an image or series of images to a user. In some embodiments, AR system 1100 includes a single display 1335A or 1335B (e.g., a near-eye display) or more than two displays 1335A and 1335B. In some embodiments, a first set of one or more displays 1335A and 1335B can be used to present an augmented-reality environment, and a second set of one or more display devices 1335A and 1335B can be used to present a virtual-reality environment. In some embodiments, one or more waveguides are used in conjunction with presenting artificial-reality content to the user of AR system 1100 (e.g., as a means of delivering light from one or more displays 1335A and 1335B to the user's eyes). In some embodiments, one or more waveguides are fully or partially integrated into the eyewear device 1102. Additionally, or alternatively to display screens, some artificial-reality systems include one or more projection systems. For example, display devices in AR system 1100 and / or VR system 1200 can include micro-LED projectors that project light (e.g., using a waveguide) into display devices, such as clear combiner lenses that allow ambient light to pass through. The display devices can refract the projected light toward a user's pupil and can enable a user to simultaneously view both artificial-reality content and the real world. Artificial-reality systems can also be configured with any other suitable type or form of image projection system. In some embodiments, one or more waveguides are provided additionally or alternatively to the one or more display(s) 1335A and 1335B.

[0181] Computing system 1320 and / or optional housing 1390 of AR system 1100or VR system 1200 can include some or all of the components of a power system 1342A and 1342B. Power systems 1342A and 1342B can include one or more charger inputs 1343, one or more PMICs 1344, and / or one or more batteries 1345A and 1344B.

[0182] Memory 1350A and 1350B may include instructions and data, some or all of which may be stored as non-transitory computer-readable storage media within the memories 1350A and 1350B. For example, memory 1350A and 1350B can include one or more operating systems 1351, one or more applications 1352, one or more communication interface applications 1353A and 1353B, one or more graphics applications 1354A and 1354B, one or more AR processing applications 1355A and 1355B, and / or any other types of data defined above or described with respect to any other embodiments discussed herein.

[0183] Memory 1350A and 1350B also include data 1360A and 1360B, which can be used in conjunction with one or more of the applications discussed above. Data 1360A and 1360B can include profile data 1361, sensor data 1362A and 1362B, media content data 1363A, AR application data 1364A and 1364B, and / or any other types of data defined above or described with respect to any other embodiments discussed herein.

[0184] In some embodiments, controller 1346 of eyewear device 1102 may process information generated by sensors 1323A and / or 1323B on eyewear device 1102 and / or another electronic device within AR system 1100. For example, controller 1346 can process information from acoustic sensors 1125-1 and 1125-2. For each detected sound, controller 1346 can perform a direction of arrival (DOA) estimation to estimate a direction from which the detected sound arrived at eyewear device 1102 of AR system 1100. As one or more of acoustic sensors 1325 (e.g., the acoustic sensors 1125-1, 1125-2) detects sounds, controller 1346 can populate an audio data set with the information (e.g., represented in FIG. 13 as sensor data 1362A and 1362B).

[0185] In some embodiments, a physical electronic connector can convey information between eyewear device 1102 and another electronic device and / or between one or more processors 1148, 1348A, 1348B of AR system 1100 or VR system 1200 and controller 1346. The information can be in the form of optical data, electrical data, wireless data, or any other transmittable data form. Moving the processing of information generated by eyewear device 1102 to an intermediary processing device can reduce weight and heat in the eyewear device, making it more comfortable and safer for a user. In some embodiments, an optional wearable accessory device (e.g., an electronic neckband) is coupled to eyeweardevice 1102 via one or more connectors. The connectors can be wired or wireless connectors and can include electrical and / or non-electrical (e.g., structural) components. In some embodiments, eyewear device 1102 and the wearable accessory device can operate independently without any wired or wireless connection between them.

[0186] In some situations, pairing external devices, such as an intermediary processing device (e.g., HIPD 506, 606, 706) with eyewear device 1102 (e.g., as part of AR system 1100) enables eyewear device 1102 to achieve a similar form factor of a pair of glasses while still providing sufficient battery and computation power for expanded capabilities. Some, or all, of the battery power, computational resources, and / or additional features of AR system 1100 can be provided by a paired device or shared between a paired device and eyewear device 1102, thus reducing the weight, heat profile, and form factor of eyewear device 1102 overall while allowing eyewear device 1102 to retain its desired functionality. For example, the wearable accessory device can allow components that would otherwise be included on eyewear device 1102 to be included in the wearable accessory device and / or intermediary processing device, thereby shifting a weight load from the user's head and neck to one or more other portions of the user's body. In some embodiments, the intermediary processing device has a larger surface area over which to diffuse and disperse heat to the ambient environment. Thus, the intermediary processing device can allow for greater battery and computation capacity than might otherwise have been possible on eyewear device 1102 standing alone. Because weight carried in the wearable accessory device can be less invasive to a user than weight carried in the eyewear device 1102, a user may tolerate wearing a lighter eyewear device and carrying or wearing the paired device for greater lengths of time than the user would tolerate wearing a heavier eyewear device standing alone, thereby enabling an artificial-reality environment to be incorporated more fully into a user's day-to-day activities.

[0187] AR systems can include various types of computer vision components and subsystems. For example, AR system 1100 and / or VR system 1200 can include one or more optical sensors such as two-dimensional (2D) or three-dimensional (3D) cameras, time-of- flight depth sensors, structured light transmitters and detectors, single-beam or sweeping laser rangefinders, 3D LiDAR sensors, and / or any other suitable type or form of optical sensor. An AR system can process data from one or more of these sensors to identify a location of a user and / or aspects of the use's real-world physical surroundings, including the locations of real-world objects within the real-world physical surroundings. In some embodiments, themethods described herein are used to map the real world, to provide a user with context about real-world surroundings, and / or to generate digital twins (e.g., interactable virtual objects), among a variety of other functions. For example, FIGS. 12A and 12B show VR system 1200 having cameras 1239A to 1239D, which can be used to provide depth information for creating a voxel field and a two-dimensional mesh to provide object information to the user to avoid collisions.

[0188] In some embodiments, AR system 1100 and / or VR system 1200 can include haptic (tactile) feedback systems, which may be incorporated into headwear, gloves, body suits, handheld controllers, environmental devices (e.g., chairs or floormats), and / or any other type of device or system, such as the wearable devices discussed herein. The haptic feedback systems may provide various types of cutaneous feedback, including vibration, force, traction, shear, texture, and / or temperature. The haptic feedback systems may also provide various types of kinesthetic feedback, such as motion and compliance. The haptic feedback may be implemented using motors, piezoelectric actuators, fluidic systems, and / or a variety of other types of feedback mechanisms. The haptic feedback systems may be implemented independently of other artificial-reality devices, within other artificial-reality devices, and / or in conjunction with other artificial-reality devices.

[0189] In some embodiments of an artificial reality system, such as AR system 1100 and / or VR system 1200, ambient light (e.g., a live feed of the surrounding environment that a user would normally see) can be passed through a display element of a respective headwearable device presenting aspects of the AR system. In some embodiments, ambient light can be passed through a portion less that is less than all of an AR environment presented within a user's field of view (e.g., a portion of the AR environment co-located with a physical object in the user's real-world environment that is within a designated boundary (e.g., a guardian boundary) configured to be used by the user while they are interacting with the AR environment). For example, a visual user interface element (e.g., a notification user interface element) can be presented at the head-wearable device, and an amount of ambient light (e.g., 15-50% of the ambient light) can be passed through the user interface element such that the user can distinguish at least a portion of the physical environment over which the user interface element is being displayed.

[0190] In some embodiments, the systems described herein may also include an eye-tracking subsystem designed to identify and track various characteristics of a user'seye(s), such as the user's gaze direction. The phrase "eye tracking" may, in some examples, refer to a process by which the position, orientation, and / or motion of an eye is measured, detected, sensed, determined, and / or monitored. The disclosed systems may measure the position, orientation, and / or motion of an eye in a variety of different ways, including through the use of various optical-based eye-tracking techniques, ultrasound-based eye-tracking techniques, etc. An eye-tracking subsystem may be configured in a number of different ways and may include a variety of different eye-tracking hardware components or other computervision components. For example, an eye-tracking subsystem may include a variety of different optical sensors, such as two-dimensional (2D) or 3D cameras, time-of-flight depth sensors, single-beam or sweeping laser rangefinders, 3D LiDAR sensors, and / or any other suitable type or form of optical sensor. In this example, a processing subsystem may process data from one or more of these sensors to measure, detect, determine, and / or otherwise monitor the position, orientation, and / or motion of the user's eye(s).

[0191] FIG. 14 is an illustration of an example system 1400 that incorporates an eye-tracking subsystem capable of tracking a user's eye(s). As depicted in FIG. 14, system 1400 may include a light source 1402, an optical subsystem 1404, an eye-tracking subsystem 1406, and / or a control subsystem 1408. In some examples, light source 1402 may generate light for an image (e.g., to be presented to an eye 1401 of the viewer). Light source 1402 may represent any of a variety of suitable devices. For example, light source 1402 can include a two-dimensional projector (e.g., a LCoS display), a scanning source (e.g., a scanning laser), or other device (e.g., an LCD, an LED display, an OLED display, an active-matrix OLED display (AMOLED), a transparent OLED display (TOLED), a waveguide, or some other display capable of generating light for presenting an image to the viewer). In some examples, the image may represent a virtual image, which may refer to an optical image formed from the apparent divergence of light rays from a point in space, as opposed to an image formed from the light ray's actual divergence.

[0192] In some embodiments, optical subsystem 1404 may receive the light generated by light source 1402 and generate, based on the received light, converging light 1420 that includes the image. In some examples, optical subsystem 1404 may include any number of lenses (e.g., Fresnel lenses, convex lenses, concave lenses), apertures, filters, mirrors, prisms, and / or other optical components, possibly in combination with actuators and / or other devices. In particular, the actuators and / or other devices may translate and / orrotate one or more of the optical com onents to alter one or more aspects of converging light 1420. Further, various mechanical couplings may serve to maintain the relative spacing and / or the orientation of the optical components in any suitable combination.

[0193] In one embodiment, eye-tracking subsystem 1406 may generate tracking information indicating a gaze angle of an eye 1401 of the viewer. In this embodiment, control subsystem 1408 may control aspects of optical subsystem 1404 (e.g., the angle of incidence of converging light 1420) based at least in part on this tracking information. Additionally, in some examples, control subsystem 1408 may store and utilize historical tracking information (e.g., a history of the tracking information over a given duration, such as the previous second or fraction thereof) to anticipate the gaze angle of eye 1401 (e.g., an angle between the visual axis and the anatomical axis of eye 1401). In some embodiments, eye-tracking subsystem 1406 may detect radiation emanating from some portion of eye 1401 (e.g., the cornea, the iris, the pupil, or the like) to determine the current gaze angle of eye 1401. In other examples, eye-tracking subsystem 1406 may employ a wavefront sensor to track the current location of the pupil.

[0194] Any number of techniques can be used to track eye 1401. Some techniques may involve illuminating eye 1401 with infrared light and measuring reflections with at least one optical sensor that is tuned to be sensitive to the infrared light. Information about how the infrared light is reflected from eye 1401 may be analyzed to determine the position(s), orientation(s), and / or motion(s) of one or more eye feature(s), such as the cornea, pupil, iris, and / or retinal blood vessels.

[0195] In some examples, the radiation captured by a sensor of eye-tracking subsystem 1406 may be digitized (i.e., converted to an electronic signal). Further, the sensor may transmit a digital representation of this electronic signal to one or more processors (for example, processors associated with a device including eye-tracking subsystem 1406). Eyetracking subsystem 1406 may include any of a variety of sensors in a variety of different configurations. For example, eye-tracking subsystem 1406 may include an infrared detector that reacts to infrared radiation. The infrared detector may be a thermal detector, a photonic detector, and / or any other suitable type of detector. Thermal detectors may include detectors that react to thermal effects of the incident infrared radiation.

[0196] In some examples, one or more processors may process the digital representation generated by the sensor(s) of eye-tracking subsystem 1406 to track themovement of eye 1401. In another example, these processors may track the movements of eye 1401 by executing algorithms represented by computer-executable instructions stored on non-transitory memory. In some examples, on-chip logic (e.g., an application-specific integrated circuit or ASIC) may be used to perform at least portions of such algorithms. As noted, eye-tracking subsystem 1406 may be programmed to use an output of the sensor(s) to track movement of eye 1401. In some embodiments, eye-tracking subsystem 1406 may analyze the digital representation generated by the sensors to extract eye rotation information from changes in reflections. In one embodiment, eye-tracking subsystem 1406 may use corneal reflections orglints (also known as Purkinje images) and / orthe center of the eye's pupil 1422 as features to track over time.

[0197] In some embodiments, eye-tracking subsystem 1406 may use the center of the eye's pupil 1422 and infrared or near-infrared, non-collimated light to create corneal reflections. In these embodiments, eye-tracking subsystem 1406 may use the vector between the center of the eye's pupil 1422 and the corneal reflections to compute the gaze direction of eye 1401. In some embodiments, the disclosed systems may perform a calibration procedure for an individual (using, e.g., supervised or unsupervised techniques) before tracking the user's eyes. For example, the calibration procedure may include directing users to look at one or more points displayed on a display while the eye-tracking system records the values that correspond to each gaze position associated with each point.

[0198] In some embodiments, eye-tracking subsystem 1406 may use two types of infrared and / or near-infrared (also known as active light) eye-tracking techniques: bright- pupil and dark-pupil eye tracking, which may be differentiated based on the location of an illumination source with respect to the optical elements used. If the illumination is coaxial with the optical path, then eye 1401 may act as a retroreflector as the light reflects off the retina, thereby creating a bright pupil effect similar to a red-eye effect in photography. If the illumination source is offset from the optical path, then the eye's pupil 1422 may appear dark because the retroreflection from the retina is directed away from the sensor. In some embodiments, bright-pupil tracking may create greater iris / pupil contrast, allowing more robust eye tracking with iris pigmentation, and may feature reduced interference (e.g., interference caused by eyelashes and other obscuring features). Bright-pupil tracking may also allow tracking in lighting conditions ranging from total darkness to a very bright environment.

[0199] In some embodiments, control subsystem 1408 may control light source 1402 and / or optical subsystem 1404 to reduce optical aberrations (e.g., chromatic aberrations and / or monochromatic aberrations) of the image that may be caused by or influenced by eye 1401. In some examples, as mentioned above, control subsystem 1408 may use the tracking information from eye-tracking subsystem 1406 to perform such control. For example, in controlling light source 1402, control subsystem 1408 may alter the light generated by light source 1402 (e.g., by way of image rendering) to modify (e.g., pre-distort) the image so that the aberration of the image caused by eye 1401 is reduced.

[0200] The disclosed systems may track both the position and relative size of the pupil (since, e.g., the pupil dilates and / or contracts). In some examples, the eye-tracking devices and components (e.g., sensors and / or sources) used for detecting and / or tracking the pupil may be different (or calibrated differently) for different types of eyes. For example, the frequency range of the sensors may be different (or separately calibrated) for eyes of different colors and / or different pupil types, sizes, and / or the like. As such, the various eye-tracking components (e.g., infrared sources and / or sensors) described herein may need to be calibrated for each individual user and / or eye.

[0201] The disclosed systems may track both eyes with and without ophthalmic correction, such as that provided by contact lenses worn by the user. In some embodiments, ophthalmic correction elements (e.g., adjustable lenses) may be directly incorporated into the artificial reality systems described herein. In some examples, the color of the user's eye may necessitate modification of a corresponding eye-tracking algorithm. For example, eyetracking algorithms may need to be modified based at least in part on the differing color contrast between a brown eye and, for example, a blue eye.

[0202] FIG. 15 is a more detailed illustration of various aspects of the eye-tracking subsystem illustrated in FIG. 14. As shown in this figure, an eye-tracking subsystem 1500 may include at least one source 1504 and at least one sensor 1506. Source 1504 generally represents any type or form of element capable of emitting radiation. In one example, source 1504 may generate visible, infrared, and / or near-infrared radiation. In some examples, source 1504 may radiate non-collimated infrared and / or near-infrared portions of the electromagnetic spectrum towards an eye 1502 of a user. Source 1504 may utilize a variety of sampling rates and speeds. For example, the disclosed systems may use sources with higher sampling rates in order to capture fixational eye movements of a user's eye 1502 and / or tocorrectly measure saccade dynamics of the user's eye 1502. As noted above, any type orform of eye-tracking technique may be used to track the user's eye 1502, including optical-based eye-tracking techniques, ultrasound-based eye-tracking techniques, etc.

[0203] Sensor 1506 generally represents any type or form of element capable of detecting radiation, such as radiation reflected off the user's eye 1502. Examples of sensor 1506 include, without limitation, a charge coupled device (CCD), a photodiode array, a complementary metal-oxide-semiconductor (CMOS) based sensor device, and / or the like. In one example, sensor 1506 may represent a sensor having predetermined parameters, including, but not limited to, a dynamic resolution range, linearity, and / or other characteristic selected and / or designed specifically for eye tracking.

[0204] As detailed above, eye-tracking subsystem 1500 may generate one or more glints. As detailed above, a glint 1503 may represent reflections of radiation (e.g., infrared radiation from an infrared source, such as source 1504) from the structure of the user's eye. In various embodiments, glint 1503 and / or the user's pupil may be tracked using an eyetracking algorithm executed by a processor (either within or external to an artificial reality device). For example, an artificial reality device may include a processor and / or a memory device in order to perform eye tracking locally and / or a transceiver to send and receive the data necessary to perform eye tracking on an external device (e.g., a mobile phone, cloud server, or other computing device).

[0205] FIG. 15 shows an example image 1505 captured by an eye-tracking subsystem, such as eye-tracking subsystem 1500. In this example, image 1505 may include both the user's pupil 1508 and a glint 1510 near the same. In some examples, pupil 1508 and / or glint 1510 may be identified using an artificial-intelligence-based algorithm, such as a computer-vision-based algorithm. In one embodiment, image 1505 may represent a single frame in a series of frames that may be analyzed continuously in order to track the eye 1502 of the user. Further, pupil 1508 and / or glint 1510 may be tracked over a period of time to determine a user's gaze.

[0206] In one example, eye-tracking subsystem 1500 may be configured to identify and measure the inter-pupillary distance (IPD) of a user. In some embodiments, eyetracking subsystem 1500 may measure and / or calculate the IPD of the user while the user is wearing the artificial reality system. In these embodiments, eye-tracking subsystem 1500 may detect the positions of a user's eyes and may use this information to calculate the user's IPD.

[0207] As noted, the eye-tracking systems or subsystems disclosed herein may track a user's eye position and / or eye movement in a variety of ways. In one example, one or more light sources and / or optical sensors may capture an image of the user's eyes. The eyetracking subsystem may then use the captured information to determine the user's inter- pupillary distance, interocular distance, and / or a 3D position of each eye (e.g., for distortion adjustment purposes), including a magnitude of torsion and rotation (i.e., roll, pitch, and yaw) and / orgaze directions for each eye. In one example, infrared light may be emitted by the eyetracking subsystem and reflected from each eye. The reflected light may be received or detected by an optical sensor and analyzed to extract eye rotation data from changes in the infrared light reflected by each eye.

[0208] The eye-tracking subsystem may use any of a variety of different methods to track the eyes of a user. For example, a light source (e.g., infrared light-emitting diodes) may emit a dot pattern onto each eye of the user. The eye-tracking subsystem may then detect (e.g., via an optical sensor coupled to the artificial reality system) and analyze a reflection of the dot pattern from each eye of the user to identify a location of each pupil of the user. Accordingly, the eye-tracking subsystem may track up to six degrees of freedom of each eye (i.e., 3D position, roll, pitch, and yaw) and at least a subset of the tracked quantities may be combined from two eyes of a user to estimate a gaze point (i.e., a 3D location or position in a virtual scene where the user is looking) and / or an IPD.

[0209] In some cases, the distance between a user's pupil and a display may change as the user's eye moves to look in different directions. The varying distance between a pupil and a display as viewing direction changes may be referred to as "pupil swim" and may contribute to distortion perceived by the user as a result of light focusing in different locations as the distance between the pupil and the display changes. Accordingly, measuring distortion at different eye positions and pupil distances relative to displays and generating distortion corrections for different positions and distances may allow mitigation of distortion caused by pupil swim by tracking the 3D position of a user's eyes and applying a distortion correction corresponding to the 3D position of each of the user's eyes at a given point in time. Thus, knowing the 3D position of each of a user's eyes may allow for the mitigation of distortion caused by changes in the distance between the pupil of the eye and the display by applying a distortion correction for each 3D eye position. Furthermore, as noted above, knowing the position of each of the user's eyes may also enable the eye-tracking subsystem to makeautomated adjustments for a user's IPD.

[0210] In some embodiments, a display subsystem may include a variety of additional subsystems that may work in conjunction with the eye-tracking subsystems described herein. For example, a display subsystem may include a varifocal subsystem, a scene-rendering module, and / or a vergence-processing module. The varifocal subsystem may cause left and right display elements to vary the focal distance of the display device. In one embodiment, the varifocal subsystem may physically change the distance between a display and the optics through which it is viewed by moving the display, the optics, or both. Additionally, moving or translating two lenses relative to each other may also be used to change the focal distance of the display. Thus, the varifocal subsystem may include actuators or motors that move displays and / or optics to change the distance between them. This varifocal subsystem may be separate from or integrated into the display subsystem. The varifocal subsystem may also be integrated into or separate from its actuation subsystem and / or the eye-tracking subsystems described herein.

[0211] In one example, the display subsystem may include a vergence-processing module configured to determine a vergence depth of a user's gaze based on a gaze point and / or an estimated intersection of the gaze lines determined by the eye-tracking subsystem. Vergence may refer to the simultaneous movement or rotation of both eyes in opposite directions to maintain single binocular vision, which may be naturally and automatically performed by the human eye. Thus, a location where a user's eyes are verged is where the user is looking and is also typically the location where the user's eyes are focused. For example, the vergence-processing module may triangulate gaze lines to estimate a distance or depth from the user associated with intersection of the gaze lines. The depth associated with intersection of the gaze lines may then be used as an approximation for the accommodation distance, which may identify a distance from the user where the user's eyes are directed. Thus, the vergence distance may allow forthe determination of a location where the user's eyes should be focused and a depth from the user's eyes at which the eyes are focused, thereby providing information (such as an object or plane of focus) for rendering adjustments to the virtual scene.

[0212] The vergence-processing module may coordinate with the eye-tracking subsystems described herein to make adjustments to the display subsystem to account for a user's vergence depth. When the user is focused on something at a distance, the user's pupilsmay be slightly farther apart than when the user is focused on something close. The eyetracking subsystem may obtain information about the user's vergence or focus depth and may adjust the display subsystem to be closer together when the user's eyes focus or verge on something close and to be farther apart when the user's eyes focus or verge on something at a distance.

[0213] The eye-tracking information generated by the above-described eyetracking subsystems may also be used, for example, to modify various aspect of how different computer-generated images are presented. For example, a display subsystem may be configured to modify, based on information generated by an eye-tracking subsystem, at least one aspect of how the computer-generated images are presented. For instance, the computer-generated images may be modified based on the user's eye movement, such that if a user is looking up, the computer-generated images may be moved upward on the screen. Similarly, if the user is looking to the side or down, the computer-generated images may be moved to the side or downward on the screen. If the user's eyes are closed, the computergenerated images may be paused or removed from the display and resumed once the user's eyes are back open.

[0214] The above-described eye-tracking subsystems can be incorporated into one or more of the various artificial reality systems described herein in a variety of ways. For example, one or more of the various components of system 1400 and / or eye-tracking subsystem 1500 may be incorporated into any of the augmented-reality systems in and / or virtual-reality systems described herein in to enable these systems to perform various eyetracking tasks (including one or more of the eye-tracking operations described herein).

[0215] The process parameters and sequence of the steps described and / or illustrated herein are given by way of example only and can be varied as desired. For example, while the steps illustrated and / or described herein may be shown or discussed in a particular order, these steps do not necessarily need to be performed in the order illustrated or discussed. The various exemplary methods described and / or illustrated herein may also omit one or more of the steps described or illustrated herein or include additional steps in addition to those disclosed.

[0216] The preceding description has been provided to enable others skilled in the art to best utilize various aspects of the exemplary embodiments disclosed herein. This exemplary description is not intended to be exhaustive or to be limited to any precise formdisclosed. Many modifications and variations are possible without departing from the scope of the present disclosure. The embodiments disclosed herein should be considered in all respects illustrative and not restrictive. Reference may be made to any claims appended hereto and their equivalents in determining the scope of the present disclosure.

[0217] As used herein, the term "substantially" in reference to a given parameter, property, or condition may mean and include to a degree that one of ordinary skill in the art would understand that the given parameter, property, or condition is met with a small degree of variance, such as within acceptable manufacturing tolerances. By way of example, depending on the particular parameter, property, or condition that is substantially met, the parameter, property, or condition may be at least approximately 90% met, at least approximately 95% met, or even at least approximately 99% met.

[0218] As used herein, the term "approximately" in reference to a particular numeric value or range of values may, in certain embodiments, mean and include the stated value as well as all values within 10% of the stated value. Thus, by way of example, reference to the numeric value "50" as "approximately 50" may, in certain embodiments, include values equal to 50±5, i.e., values within the range 45 to 55.

[0219] Uni ess otherwise noted, the terms "connected to" and "coupled to" (and their derivatives), as used in the specification and / or claims, are to be construed as permitting both direct and indirect (i.e., via other elements or components) connection. In addition, the terms "a" or "an," as used in the specification and / or claims, are to be construed as meaning "at least one of." Finally, for ease of use, the terms "including" and "having" (and their derivatives), as used in the specification and / or claims, are interchangeable with and have the same meaning as the word "comprising."

[0220] It will be understood that when an element such as a layer or a region is referred to as being formed on, deposited on, or disposed "on" or "over" another element, it may be located directly on at least a portion of the other element, orone or more intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly over" another element, it may be located on at least a portion of the other element, with no intervening elements present.

[0221] While various features, elements or steps of particular embodiments may be disclosed using the transitional phrase "comprising," it is to be understood that alternative embodiments, including those that may be described using the transitional phrases"consisting of" or "consisting essentially of," are implied. Thus, for example, implied alternative embodiments to a lens that comprises or includes polycarbonate include embodiments where a lens consists essentially of polycarbonate and embodiments where a lens consists of polycarbonate.

Claims

WHAT IS CLAIMED IS:

1. A device comprising: a first light source; a second light source; a beam combiner; an optical scanner; and a controller, wherein: the first light source is a first self-mixing interferometry laser including a first optical cavity; the second light source is a second self-mixing interferometry laser including a second optical cavity; the beam combiner is configured to provide a combined light beam comprising a first light beam received from the first light source and a second light beam received from the second light source; the optical scanner is configured to receive the combined light beam and to scan the combined light beam over an object; returned light from the object is directed towards the first optical cavity and the second optical cavity; and the controller is configured to determine a distance to the object based on selfmixing interference signals received from the first light source and the second light source.

2. The device of claim 1, wherein the first light source comprises a first laser diode configured to emit light having a first emission wavelength and the second light source comprises a second laser diode configured to emit light having a second emission wavelength.

3. The device of claim 1 or 2, wherein a photodetector is located within at least one of the first light source and the second light source.

4. A device comprising: a first light source comprising a first laser diode and a first optical cavity; a second light source comprising a second laser diode and a second optical cavity; a beam combiner; an optical scanner; and a controller, wherein:the beam combiner is configured to provide a combined light beam comprising a first light beam received from the first light source and a second light beam received from the second light source; the optical scanner is configured to receive the combined light beam and to scan the combined light beam over an object; returned light from the object is directed towards the first optical cavity and the second optical cavity; and the controller is configured to determine a distance to the object based on selfmixing interference signals received from the first light source and the second light source.

5. The device of claim 4, wherein: the first light source comprises a first self-mixing interferometry laser; and the second light source comprises a second self-mixing interferometry laser.

6. The device of claim 4 or 5, wherein: the first laser diode is configured to emit light having a first emission wavelength; and the second laser diode is configured to emit light having a second emission wavelength.

7. The device of any one of the preceding claims, wherein the beam combiner comprises a polarization beam combiner or a chromatic beam combiner.

8. The device of any one of the preceding claims, wherein the optical scanner comprises a MEMS scanning micromirror.

9. The device of any one of the preceding claims, wherein: the first light source has a first emission wavelength; the second light source has a second emission wavelength; and the first emission wavelength and the second emission wavelength differ by between 1 nm and 20 nm.

10. The device of any one of the preceding claims, wherein the device is sized and dimensioned to be incorporated into a wearable system.

11. A method comprising: illuminating an object using first and second laser beams provided by first and second lasers and having an emission wavelength difference; detecting first and second self-mixing interferometry signals from the first and secondlasers using light returned from the object to the first and second lasers; and determining a distance to the object using the first and second self-mixing interferometry signals.

12. The method of claim 11, wherein the first and second laser beams are combined prior to illuminating the object.

13. The method of claim 11 or 12, wherein the first laser comprises a first optical cavity and the second laser comprises a second optical cavity.

14. The method of any one of claims 11 to 13, wherein the second self-mixing interference signal from the second laser is subtracted from the first self-mixing interference signal from the first laser.

15. The method of any one of claims 11 to 14, wherein determining the distance to the object comprises determining a frequency difference between the first and second selfmixing interferometry signals; and / or determining a velocity difference between the first and second self-mixing interferometry signals.

Images