JP2023514571A - delayed audio tracking - Google Patents

Abstract

Systems and methods for presenting mixed reality audio are disclosed. In an exemplary method, audio is presented to a user of a wearable head device. A first position of the user's head at a first time is determined based on one or more sensors of the wearable head device. A second position of the user's head at a second time after the first time is determined based on the one or more sensors. An audio signal is determined based on the difference between the first position and the second position. The audio signal is presented to the user via the wearable head device's speaker. Determining the audio signal includes determining the origin of the audio signal within the virtual environment. Presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin.

Description

(Cross reference to related applications)
This application claims the benefit of US Provisional Application No. 62/976,986, filed February 14, 2020, the contents of which are hereby incorporated by reference in its entirety.

TECHNICAL FIELD This disclosure relates generally to systems and methods for presenting audio to users, and more particularly to systems and methods for presenting audio to users in mixed reality environments.

Virtual environments are ubiquitous in computing environments and include video games (where the virtual environment can represent a game world), maps (where the virtual environment can represent terrain to be navigated), simulations (where the virtual environment can represent , can simulate a real environment), digital storytelling (where virtual characters can interact with each other in a virtual environment), and many other applications. Modern computer users are generally comfortable perceiving and interacting with virtual environments. However, a user's experience with a virtual environment can be limited by the technology for presenting the virtual environment. For example, conventional displays (e.g., 2D display screens) and audio systems (e.g., fixed speakers) are incapable of enabling virtual environments to create an engaging, realistic, and immersive experience. can be possible.

Virtual reality (“VR”), augmented reality (“AR”), mixed reality (“MR”), and related technologies (collectively, “XR”) allow users of XR systems to Share the ability to present sensory information that corresponds to the virtual environment represented. Such systems can provide uniquely increased immersion and realism by combining virtual visual and audio cues with real sights and sounds. Therefore, it may be desirable to present digital sounds to a user of an XR system in such a way that the sounds feel natural and are consistent with the user's expectations of sounds in the user's real environment. Generally, users expect that virtual sounds will take on the acoustic properties of the real environment in which they hear them. For example, a user of an XR system in a large concert hall would expect the virtual sound of the XR system to have a cavernous sound quality, and conversely a user in a small apartment would expect the sound to be more You would expect it to be attenuated, close, and immediate. In addition to matching the acoustic properties of the virtual sounds with the real and/or virtual environment, realism is further enhanced by spatializing the virtual sounds. For example, a virtual object may visually fly past the user from behind, and the user may expect corresponding virtual sounds to similarly reflect the spatial movement of the virtual object relative to the user.

Existing technologies often do not consider the user's surroundings and do not accommodate the spatial movement of virtual objects, which can compromise the user experience, lead to a sense of inauthenticity, present virtual audio, etc. lacks these expectations by The user's observation of the XR system is that although the user may be relatively tolerant of visual inconsistencies (e.g., inconsistencies in lighting) between the virtual content and the real environment, the user may be more sensitive to auditory inconsistencies. Show that you can be sensitive. Our unique auditory experiences, which are continually refined throughout our lives, can make us acutely aware of how our physical environment affects the sounds we hear, We can be very sensitive to sounds that do not match our expectations. In XR systems, such discrepancies can be offensive and can turn an immersive and engaging experience into a gimmicky mimic. In extreme examples, auditory inconsistency can lead to motion sickness and other adverse effects due to the inability of the inner ear to reconcile auditory stimuli with their corresponding visual cues.

Because of our sensitivity to our audio perception, an immersive audio experience can be equally, if not more important than, an immersive visual experience. Because of the variety of sensing and computing power available to XR systems, XR systems can spatialize sound by splitting it into one or more channels, making it much more immersive than conventional audio systems. It can be positioned to provide an audio experience. For example, stereo headphones may use left and right channels to present audio to the user, giving the appearance of sounds originating from different directions. Some stereo headphones may simulate additional channels (such as 5.1 channels) to further enhance audio spatialization. However, conventional systems can suffer from the fact that spatialized sound locations are static with respect to the user. For example, a guitar sound that may be presented to a user as occurring five feet from the user's left ear may not dynamically change to the user as he rotates his head. Such static behavior may not reflect the audio behavior within the "real" environment. A person watching a live orchestra may experience slight variations in their audio experience, for example, based on small head movements. These subacoustic behaviors can be cumulative and add to the immersive audio experience. Therefore, it is desirable to develop audio systems and methods for XR systems to enhance the user's audio experience.

By taking into account the characteristics of the user's physical environment, the systems and methods described herein are able to compare what a user would hear to virtual sounds, whether they are real sounds that are naturally generated within the environment. can be simulated as By presenting virtual sounds in a manner that is faithful to the way sounds behave in the real world, users may experience an increased sense of connection with the mixed reality environment. Similarly, by presenting location-aware virtual content that responds to the user's movement and environment, the content becomes more subjective, interactive, and realistic, e.g., the user's experience at point A is , may be wholly different from that experience at point B. This enhanced realism and interaction is for new applications of mixed reality, such as those that use spatially aware audio to enable new forms of gameplay, social features, or interactive behavior. can provide a foundation.

Embodiments of the present disclosure describe systems and methods for presenting mixed reality audio. According to embodiments of the present disclosure, audio is presented to the user of the wearable head device. A first position of the user's head at a first time is determined based on one or more sensors of the wearable head device. A second position of the user's head at a second time after the first time is determined based on the one or more sensors. An audio signal is determined based on the difference between the first position and the second position. The audio signal is presented to the user via the wearable head device's speaker. Determining the audio signal includes determining the origin of the audio signal within the virtual environment. Presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin. Determining the origin of the audio signal includes applying an offset to the position of the user's head.

1A-1C illustrate an exemplary mixed reality environment, according to some embodiments. 1A-1C illustrate an exemplary mixed reality environment, according to some embodiments. 1A-1C illustrate an exemplary mixed reality environment, according to some embodiments.

2A-2D illustrate components of an exemplary mixed reality system that may be used to generate and interact with a mixed reality environment, according to some embodiments. 2A-2D illustrate components of an exemplary mixed reality system that may be used to generate and interact with a mixed reality environment, according to some embodiments. 2A-2D illustrate components of an exemplary mixed reality system that may be used to generate and interact with a mixed reality environment, according to some embodiments. 2A-2D illustrate components of an exemplary mixed reality system that may be used to generate and interact with a mixed reality environment, according to some embodiments.

FIG. 3A illustrates an exemplary mixed reality handheld controller that may be used to provide input to a mixed reality environment, according to some embodiments.

FIG. 3B illustrates an exemplary auxiliary unit that may be used with an exemplary mixed reality system, according to some embodiments.

FIG. 4 illustrates an exemplary functional block diagram for an exemplary mixed reality system, according to some embodiments.

FIG. 5 illustrates an example of mixed reality spatialized audio, according to some embodiments.

6A-6C illustrate examples of mixed reality spatialized audio, according to some embodiments. 6A-6C illustrate examples of mixed reality spatialized audio, according to some embodiments. 6A-6C illustrate examples of mixed reality spatialized audio, according to some embodiments.

DETAILED DESCRIPTION In the following description of the embodiments, reference is made to the accompanying drawings, which form a part hereof and in which, by way of illustration, specific embodiments that may be practiced are shown. It is to be understood that other embodiments may be used and structural changes may be made without departing from the scope of the disclosed embodiments.

mixed reality environment

Like all people, users of mixed reality systems reside within a real environment, ie, a three-dimensional portion of the "real world" and all of its content is perceivable by the user. For example, a user may use normal human senses: sight, hearing, touch, taste and smell to perceive the real environment and interact with the real environment by moving his or her body within the real environment. works. Locations in the real environment can be described as coordinates in a coordinate space. For example, coordinates may include latitude, longitude, and altitude relative to sea level, distance in three orthogonal dimensions from a reference point, or other suitable values. Similarly, vectors can describe quantities that have direction and magnitude in coordinate space.

A computing device may maintain a representation of a virtual environment, eg, in memory associated with the device. As used herein, a virtual environment is a computed representation of three-dimensional space. A virtual environment can include representations of any objects, actions, signals, parameters, coordinates, vectors, or other properties associated with that space. In some examples, the circuitry (eg, processor) of the computing device can maintain and update the state of the virtual environment. That is, the processor can determine the state of the virtual environment at the second time t1 based on data associated with the virtual environment and/or input provided by the user at the first time t0. For example, an object in the virtual environment is located at a first coordinate at time t0, has certain programmed physical parameters (e.g., mass, coefficient of friction), and the input received from the user is the force If it indicates that it should be applied to the object in some direction vector, the processor can apply the laws of kinematics and use the basic mechanics to determine the location of the object at time t1. The processor may use any suitable information known about the virtual environment and/or any suitable input to determine the state of the virtual environment at time t1. In maintaining and updating the state of the virtual environment, the processor includes software associated with creating and deleting virtual objects within the virtual environment, software (e.g., scripts) for defining the behavior of virtual objects or characters within the virtual environment. , software for defining the behavior of signals (e.g., audio signals) within the virtual environment, software for creating and updating parameters associated with the virtual environment, software for generating audio signals within the virtual environment, input and software for handling outputs, software for implementing network behavior, software for applying asset data (e.g. animation data for moving virtual objects over time), or many other possibilities. Any suitable software can be executed, including

An output device, such as a display or speakers, can present any or all aspects of the virtual environment to the user. For example, the virtual environment may include virtual objects (which may include representations of inanimate objects, people, animals, lights, etc.) that may be presented to the user. The processor determines a view of the virtual environment (e.g., corresponding to a "camera" with origin coordinates, viewing axis, and frustum) and renders on the display a viewable scene of the virtual environment corresponding to that view. be able to. Any suitable rendering technique may be used for this purpose. In some embodiments, the viewable scene may include only some virtual objects within the virtual environment and exclude certain other virtual objects. Similarly, the virtual environment may include audio aspects, which may be presented to the user as one or more audio signals. For example, a virtual object within the virtual environment may generate a sound that originates from the object's location coordinates (eg, a virtual character may speak or produce a sound effect), or the virtual environment may represent a particular location. may be associated with musical cues or ambient sounds, which may or may not be associated with. The processor corresponds to audio signals corresponding to "listener" coordinates, e.g., synthesis of sounds in a virtual environment, mixed and processed to simulate audio signals that would be heard by a listener in listener coordinates. , an audio signal can be determined and presented to the user via one or more speakers.

Since the virtual environment exists only as a computed structure, the user cannot perceive it directly using normal senses. Instead, the user can perceive the virtual environment only indirectly, as presented to the user, eg, by a display, speakers, tactile output device, or the like. Similarly, a user cannot touch, manipulate, or otherwise interact with the virtual environment directly, but input data through an input device or sensor, using device or sensor data. can be provided to the processor, which can then update the virtual environment. For example, a camera sensor can provide optical data indicating that a user is attempting to move an object in the virtual environment, and the processor uses that data to move the object accordingly within the virtual environment. can be answered.

Mixed reality systems provide users with aspects of real and virtual environments using, for example, transmissive displays and/or one or more speakers (which may be incorporated into wearable head devices, for example). Combined, a mixed reality environment (“MRE”) can be presented. In some embodiments, one or more speakers may be external to the head mounted wearable unit. As used herein, an MRE is a simultaneous representation of a real environment and a corresponding virtual environment. In some examples, corresponding real and virtual environments share a single coordinate space. In some embodiments, the real coordinate space and the corresponding virtual coordinate space are related to each other by a transformation matrix (or other suitable representation). Thus, a single coordinate (along with a transformation matrix in some embodiments) may define a first location in the real environment and a second corresponding location in the virtual environment, and vice versa. It is the same.

In an MRE, virtual objects (eg, in a virtual environment associated with the MRE) may correspond to real objects (eg, in a real environment associated with the MRE). For example, if the MRE's real environment includes real lampposts (real objects) at certain location coordinates, the MRE's virtual environment may include virtual lampposts (virtual objects) at corresponding location coordinates. As used herein, a real object in combination with its corresponding virtual object constitutes a "mixed reality object." It is not necessary that the virtual objects perfectly match or match the corresponding real objects. In some implementations, a virtual object can be a simplified version of the corresponding real object. For example, if the real environment includes a real lamppost, the corresponding virtual object may include a cylinder of approximately the same height and radius as the real lamppost (reflecting that the lamppost may be approximately cylindrical in shape). do). Such simplification of virtual objects can allow for computational efficiency and can simplify computations to be performed on such virtual objects. Furthermore, in some implementations of the MRE, not all real objects in the real environment may be associated with corresponding virtual objects. Similarly, in some implementations of the MRE, not all virtual objects within the virtual environment may be associated with corresponding real objects. That is, some virtual objects may exist only within the MRE's virtual environment without any real-world counterparts.

In some embodiments, virtual objects may have properties that differ, sometimes significantly, from those of corresponding real objects. For example, the real environment in the MRE may include a green two-branched cactus, a spiny inanimate object, while the corresponding virtual object in the MRE has human facial features and a surly demeanor. It may have the properties of a green two-armed virtual character accompanying it. In this example, the virtual object resembles its corresponding real object in some characteristics (color, number of arms), but differs from the real object in other characteristics (facial features, personality). Thus, a virtual object represents a real object in a creative, abstract, exaggerated, or fictitious manner, or imparts behavior (e.g., human personality) to an otherwise inanimate real object. have the potential to In some examples, the virtual object is a purely fictitious creation with no real-world counterpart (eg, a virtual monster in a virtual environment, perhaps in a location corresponding to the void in the real environment). may

Mixed reality systems, which present the user with a virtual environment while obscuring the real environment, compared to VR systems, which present MRE, allow the real environment to remain perceptible while the virtual environment is presented. provide the advantage of being A user of the mixed reality system is thus able to experience and interact with the corresponding virtual environment using visual and audio cues associated with the real environment. As an example, a user of a VR system can perceive virtual objects displayed within a virtual environment because, as mentioned above, the user cannot directly perceive or interact with the virtual environment. However, users of MR systems find it intuitive to interact with virtual objects by seeing, hearing, and touching corresponding real objects in their own real environment. and can be found to be natural. This level of interaction can enhance the user's sense of immersion, connection, and involvement with the virtual environment. Similarly, by presenting real and virtual environments simultaneously, mixed reality systems can reduce the negative psychological sensations (e.g., cognitive dissonance) and negative physical sensations (e.g., motion sickness) associated with VR systems. ) can be reduced. Mixed reality systems also offer many possibilities for applications that can augment or modify our experience of the real world.

FIG. 1A illustrates an exemplary real-world environment 100 in which a user 110 uses a mixed reality system 112. FIG. Mixed reality system 112 may include a display (eg, transmissive display) and one or more speakers, and one or more sensors (eg, cameras), eg, as described below. . The real environment 100 shown includes a rectangular room 104A in which a user 110 stands, and real objects 122A (lamp), 124A (table), 126A (sofa), and 128A (painting). Room 104 A also includes location coordinates 106 , which may be considered the origin of real environment 100 . As shown in FIG. 1A, environment/world coordinate system 108 (comprising x-axis 108X, y-axis 108Y, and z-axis 108Z), with its origin at point 106 (world coordinates), is real environment 100. We can define a coordinate space for In some embodiments, origin 106 of environment/world coordinate system 108 may correspond to where mixed reality system 112 is powered on. In some embodiments, the origin 106 of the environment/world coordinate system 108 may be reset during operation. In some examples, user 110 may be viewed as a real object within real environment 100 . Similarly, body parts (eg, hands, feet) of user 110 may be considered real objects within real environment 100 . In some embodiments, a user/listener/head coordinate system 114 (x-axis 114X, y-axis 114Y, and z - with axis 114Z) may define a coordinate space for the user/listener/head on which mixed reality system 112 is located. An origin 115 of user/listener/head coordinate system 114 may be defined with respect to one or more components of mixed reality system 112 . For example, the origin 115 of the user/listener/head coordinate system 114 may be defined relative to the display of the mixed reality system 112 , such as during initial calibration of the mixed reality system 112 . A matrix (which may include translation matrices and quaternion matrices or other rotation matrices) or other suitable representation is between the user/listener/head coordinate system 114 space and the environment/world coordinate system 108 space. Transformations can be characterized. In some embodiments, left ear coordinates 116 and right ear coordinates 117 may be defined relative to origin 115 of user/listener/head coordinate system 114 . A matrix (which may include translation and quaternion matrices or other rotation matrices) or other suitable representation is the relationship between left ear coordinates 116 and right ear coordinates 117 and user/listener/head coordinate system 114 space. Transformation between can be characterized. User/listener/head coordinate system 114 may simplify the representation of location relative to the user's head or head-mounted device, eg, relative to environment/world coordinate system 108 . Using simultaneous localization and mapping (SLAM), visual odometry, or other techniques, the transformation between the user coordinate system 114 and the environment coordinate system 108 can be determined and updated in real time.

FIG. 1B illustrates an exemplary virtual environment 130 that corresponds to real environment 100 . Virtual environment 130 shown includes virtual rectangular room 104B corresponding to real rectangular room 104A, virtual object 122B corresponding to real object 122A, virtual object 124B corresponding to real object 124A, and virtual object 124B corresponding to real object 126A. 126B. Metadata associated with virtual objects 122B, 124B, 126B may include information derived from corresponding real objects 122A, 124A, 126A. Virtual environment 130 additionally includes virtual monster 132 , which does not correspond to any real object within real environment 100 . Real object 128 A in real environment 100 does not correspond to any virtual object in virtual environment 130 . A persistent coordinate system 133 (comprising x-axis 133X, y-axis 133Y, and z-axis 133Z), with its origin at point 134 (persistent coordinates), may define a coordinate space for virtual content. . An origin 134 of persistent coordinate system 133 may be defined relative to/with respect to one or more real objects, such as real object 126A. A matrix (which may include a translation matrix and a quaternion matrix or other rotation matrix) or other suitable representation characterizes the transformation between the persistent coordinate system 133 space and the environment/world coordinate system 108 space. be able to. In some embodiments, virtual objects 122 B, 124 B, 126 B, and 132 may each have their own persistent coordinate point relative to origin 134 of persistent coordinate system 133 . In some embodiments, multiple persistent coordinate systems may exist, and virtual objects 122B, 124B, 126B, and 132 each have their own persistent coordinates relative to one or more persistent coordinate systems. may have points.

1A and 1B, environment/world coordinate system 108 defines a shared coordinate space for both real environment 100 and virtual environment 130 . In the example shown, the coordinate space has its origin at point 106 . Furthermore, the coordinate space is defined by three identical orthogonal axes (108X, 108Y, 108Z). Thus, a first location in real environment 100 and a second corresponding location in virtual environment 130 can be described with respect to the same coordinate space. This simplifies identifying and displaying corresponding locations in real and virtual environments, as the same coordinates can be used to identify both locations. However, in some implementations, the corresponding real and virtual environments need not use a shared coordinate space. For example, in some embodiments (not shown), matrices (which may include translation matrices and quaternion matrices or other rotation matrices) or other suitable representations are represented in real-environment coordinate space and virtual-environment coordinate space , can be characterized.

FIG. 1C illustrates exemplary MRE 150 simultaneously presenting aspects of real environment 100 and virtual environment 130 to user 110 via mixed reality system 112 . In the illustrated example, MRE 150 simultaneously provides user 110 with real objects 122A, 124A, 126A, and 128A from real environment 100 (eg, via a transparent portion of the display of mixed reality system 112) and virtual Virtual objects 122B, 124B, 126B, and 132 from environment 130 (eg, via active display portions of the display of mixed reality system 112) are presented. As noted above, origin 106 acts as the origin for the coordinate space corresponding to MRE 150, and coordinate system 108 defines the x-, y-, and z-axes for the coordinate space.

In the illustrated example, the mixed reality objects include corresponding pairs of real and virtual objects (ie, 122A/122B, 124A/124B, 126A/126B) that occupy corresponding locations in coordinate space 108 . In some examples, both real and virtual objects may be visible to user 110 at the same time. This may be desirable, for example, in instances where a virtual object presents information designed to enhance the view of the corresponding real object (the virtual object presents missing parts of ancient damaged statues, museum applications, etc.). In some embodiments, virtual objects (122B, 124B, and/or 126B) may be displayed (e.g., pixel via Active Pixelated Occlusion, which uses an occlusion shutter). This may be desirable, for example, in instances where virtual objects act as visual replacements for corresponding real objects (such as interactive storytelling applications, where inanimate real objects become "living" characters).

In some examples, a real object (eg, 122A, 124A, 126A) may be associated with virtual content or helper data that does not necessarily constitute a virtual object. Virtual content or helper data can facilitate the processing or handling of virtual objects within a mixed reality environment. For example, such virtual content may include two-dimensional representations of corresponding real objects, custom asset types associated with corresponding real objects, or statistical data associated with corresponding real objects. This information can enable or facilitate computations involving real objects without incurring unnecessary computational overhead.

In some embodiments, the presentations described above may also incorporate audio aspects. For example, in MRE 150 , virtual monster 132 may be associated with one or more audio signals, such as footstep effects, generated as the monster walks around MRE 150 . As further described below, the processor of mixed reality system 112 computes an audio signal corresponding to all such sound mixing and processed synthesis within MRE 150 and contained within mixed reality system 112. Audio signals may be presented to user 110 via one or more speakers and/or one or more external speakers.

An exemplary mixed reality system

Exemplary mixed reality system 112 includes a display (which may be an eyepiece display, which may include left and right transmissive displays, and associated components for coupling light from the display to the user's eye) and left and right A speaker (e.g., positioned adjacent to the user's left and right ears, respectively), an inertial measurement unit (IMU) (e.g., mounted on the temple arm of the head device), and a quadrature coil electromagnetic receiver ( left and right cameras (e.g., mounted on the left temple), oriented away from the user (e.g., depth (time-of-flight) cameras), and left and right eye cameras oriented toward the user. (eg, to detect user eye movement). However, mixed reality system 112 may incorporate any suitable display technology and any suitable sensors (eg, optical, infrared, acoustic, LIDAR, EOG, GPS, magnetic). Additionally, mixed reality system 112 may incorporate networking features (eg, Wi-Fi capabilities) to communicate with other devices and systems, including other mixed reality systems. Mixed reality system 112 may further include a battery (which may be mounted in an auxiliary unit such as a beltpack designed to be worn around the user's waist), a processor, and memory. The wearable head device of mixed reality system 112 may include a tracking component, such as an IMU or other suitable sensor, configured to output a coordinate set of the wearable head device relative to the user's environment. In some examples, the tracking component may provide input to the processor to implement simultaneous localization and mapping (SLAM) and/or visual odometry algorithms. In some examples, the mixed reality system 112 may also include a handheld controller 300 and/or an auxiliary unit 320, which may be a wearable beltpack, as further described below.

2A-2D illustrate components of an exemplary mixed reality system 200 (which may correspond to mixed reality system 112) that may be used to present an MRE (which may correspond to MRE 150) or other virtual environment to a user. do. FIG. 2A illustrates a perspective view of wearable head device 2102 included within exemplary mixed reality system 200 . FIG. 2B illustrates a top view of wearable head device 2102 worn on user's head 2202 . FIG. 2C illustrates a front view of wearable head device 2102 . FIG. 2D illustrates an edge view of an exemplary eyepiece 2110 of wearable head device 2102 . As shown in FIGS. 2A-2C, the exemplary wearable head device 2102 includes an exemplary left eyepiece (eg, left transparent waveguide set eyepiece) 2108 and an exemplary right eyepiece (eg, right transparent waveguide set eyepiece) 2108 . wave tube set eyepiece) 2110. Each eyepiece 2108 and 2110 includes a transmissive element through which the real environment is visible and a display element for presenting a display (e.g., via image-wise modulated light) that overlaps the real environment. can include In some embodiments, such display elements can include surface diffractive optical elements for controlling the flow of modulated light from image to image. For example, the left eyepiece 2108 can include a left incoupling grating set 2112 , a left orthogonal pupil expansion (OPE) grating set 2120 , and a left exit (output) pupil expansion (EPE) grating set 2122 . Similarly, right eyepiece 2110 may include right incoupling grating set 2118 , right OPE grating set 2114 , and right EPE grating set 2116 . The image-wise modulated light can be transferred to the user's eye via incoupling gratings 2112 and 2118 , OPEs 2114 and 2120 , and EPEs 2116 and 2122 . Each incoupling grating set 2112 , 2118 can be configured to deflect light towards its corresponding OPE grating set 2120 , 2114 . Each OPE grating set 2120, 2114 may be designed to progressively deflect light downward toward its associated EPE 2122, 2116, thereby horizontally extending the exit pupil being formed. can. Each EPE 2122, 2116 directs at least a portion of the light received from its corresponding OPE grating set 2120, 2114 outward to a user eyebox location (not shown) defined behind the eyepieces 2108, 2110. so that the exit pupil formed in the eyebox extends vertically. Alternatively, instead of incoupling grating sets 2112 and 2118, OPE grating sets 2114 and 2120, and EPE grating sets 2116 and 2122, eyepieces 2108 and 2110 are used to couple the image-wise modulated light to the user's eye. Gratings and/or other arrangements of refractive and reflective features may be included to control the .

In some examples, the wearable head device 2102 can include a left temple arm 2130 and a right temple arm 2132, the left temple arm 2130 including the left speaker 2134 and the right temple arm 2134. 2132 includes right speaker 2136 . The quadrature coil electromagnetic receiver 2138 may be located in the left temple piece or another suitable location within the wearable head unit 2102 . An inertial measurement unit (IMU) 2140 may be located in the right temple arm 2132 or another suitable location within the wearable head device 2102 . The wearable head device 2102 may also include a left depth (eg, time of flight) camera 2142 and a right depth camera 2144. Depth cameras 2142, 2144 can preferably be oriented in different directions so that together they cover a wider field of view.

2A-2D, a left source of image-wise modulated light 2124 can be optically coupled into a left eyepiece 2108 through a left incoupling grating set 2112 to provide an image A right source of modulated light 2126 can be optically coupled into the right eyepiece 2110 through a right incoupling grating set 2118 . Sources of image-wise modulated light 2124, 2126 include, for example, fiber optic scanners, digital light processing (DLP) chips or electronic light modulators such as liquid crystal on silicon (LCoS) modulators, projectors, or per side. It can include an emissive display such as a micro light emitting diode (μLED) or micro organic light emitting diode (μOLED) panel coupled into an incoupling grid set 2112, 2118 using one or more lenses. can. The input coupling grating set 2112, 2118 deflects the light from the image-wise modulated light sources 2124, 2126 to angles above the critical angle for total internal reflection (TIR) for the eyepieces 2108, 2110. can be done. The OPE grating sets 2114, 2120 progressively deflect propagating light downward toward the EPE grating sets 2116, 2122 by TIR. The EPE grating sets 2116, 2122 progressively couple light towards the user's face, including the pupils of the user's eyes.

In some embodiments, left eyepiece 2108 and right eyepiece 2110 each include multiple waveguides 2402, as shown in FIG. 2D. For example, each eyepiece 2108, 2110 can include multiple individual waveguides, each dedicated to a separate color channel (eg, red, blue, and green). In some embodiments, each eyepiece 2108, 2110 can include multiple sets of such waveguides, each set configured to impart a different wavefront curvature to the emitted light. be. The wavefront curvature may be convex to the user's eye, for example, to present a virtual object positioned at some distance in front of the user (eg, a distance corresponding to the reciprocal of the wavefront curvature). In some embodiments, the EPE grating sets 2116, 2122 can include curved grating grooves to produce convex wavefront curvature by modifying the Poynting vector of light exiting across each EPE.

In some embodiments, stereoscopically adjusted left and right eye images are combined with light modulators 2124, 2126 and eyepiece 2108 for each image to create the perception that the displayed content is three-dimensional. , 2110 to the user. The perceived realism of the presentation of a three-dimensional virtual object is to position the waveguide (and thus the corresponding wavefront curvature) such that the virtual object appears at a distance approximating the distance exhibited by the stereoscopic left and right images. Can be enhanced by selection. The technique also suffers from some users, which can be caused by differences between the depth perception cues provided by the stereoscopic left and right eye images and the human eye's automatic accommodation (e.g., object distance dependent focus). can reduce motion sickness.

FIG. 2D illustrates an edge view from the top of right eyepiece 2110 of exemplary wearable head device 2102 . As shown in FIG. 2D, the plurality of waveguides 2402 can include a first subset 2404 of three waveguides and a second subset 2406 of three waveguides. The two subsets of waveguides 2404, 2406 can be distinguished by different EPE gratings featuring different grating line curvatures to impart different wavefront curvatures to the emerging light. Within each of the waveguide subsets 2404, 2406, each waveguide is for coupling a different spectral channel (eg, one of the red, green, and blue spectral channels) to the user's right eye 2206. can be used. (Although not shown in FIG. 2D, the structure of left eyepiece 2108 is similar to that of right eyepiece 2110.)

FIG. 3A illustrates an exemplary handheld controller component 300 of mixed reality system 200 . In some examples, handheld controller 300 includes a gripping portion 346 and one or more buttons 350 disposed along top surface 348 . In some examples, the button 350 is located on the handheld controller 300, for example, in conjunction with a camera or other optical sensor (which may be mounted within the head unit (eg, wearable head device 2102) of the mixed reality system 200). may be configured for use as an optical tracking target for tracking the six degrees of freedom (6DOF) motion of the . In some examples, handheld controller 300 includes a tracking component (eg, an IMU or other suitable sensor) for detecting position or orientation, such as position or orientation relative to wearable head device 2102 . In some examples, such tracking components may be located within the handle of handheld controller 300 and/or may be mechanically coupled to the handheld controller. The handheld controller 300 controls one or more of the button presses, or the position, orientation, and/or movement of the handheld controller 300 (eg, via an IMU). can be configured to provide a higher output signal. Such output signals may be used as inputs to the processor of mixed reality system 200 . Such inputs may correspond to the position, orientation, and/or movement of the handheld controller (and for that matter, the position, orientation, and/or movement of the user's hand holding the controller). Such input may also correspond to a user pressing button 350 .

FIG. 3B illustrates an exemplary auxiliary unit 320 of mixed reality system 200 . Auxiliary unit 320 may include a battery to provide energy and operate system 200 and may include a processor to execute programs and operate system 200 . As shown, the exemplary auxiliary unit 320 includes a clip 2128 for attaching the auxiliary unit 320 to a user's belt, or the like. It will also be apparent that other form factors are suitable for auxiliary unit 320, including form factors that do not involve mounting the unit to the user's belt. In some examples, the auxiliary unit 320 is coupled to the wearable head device 2102 through multi-tubular cables, which can include electrical wires and optical fibers, for example. A wireless connection between the auxiliary unit 320 and the wearable head device 2102 can also be used.

In some examples, mixed reality system 200 may include one or more microphones to detect sounds and provide corresponding signals to the mixed reality system. In some examples, a microphone may be attached to or integrated with the wearable head device 2102 and may be configured to detect the user's voice. In some examples, a microphone may be attached to or integrated with handheld controller 300 and/or auxiliary unit 320 . Such microphones may be configured to detect environmental sounds, ambient noise, user or third party speech, or other sounds.

FIG. 4 illustrates an exemplary functional block diagram that may correspond to an exemplary mixed reality system, such as mixed reality system 200 (which may correspond to mixed reality system 112 with respect to FIG. 1) described above. As shown in FIG. 4, an exemplary handheld controller 400B (which may correspond to handheld controller 300 (“totem”)) includes a totem/wearable head device 6 degree of freedom (6DOF) totem subsystem 404A and includes an exemplary Wearable head device 400A (which may correspond to wearable head device 2102) includes a totem/wearable head device 6DOF subsystem 404B. In an embodiment, the 6DOF totem subsystem 404A and the 6DOF subsystem 404B cooperate to provide six coordinates of the handheld controller 400B relative to the wearable head device 400A (e.g., offsets in three translational directions and along three axes). rotation). The six degrees of freedom may be expressed relative to the coordinate system of wearable head device 400A. The three translation offsets may be represented as X, Y, and Z offsets, translation matrices, or some other representation within such a coordinate system. The rotational degrees of freedom may be represented as sequences of yaw, pitch, and roll rotations, as rotation matrices, as quaternions, or as some other representation. In some examples, the wearable head device 400A, one or more depth cameras 444 (and/or one or more non-depth cameras) included within the wearable head device 400A, and/or One or more optical targets (eg, button 350 of handheld controller 400B as described above or a dedicated optical target included within handheld controller 400B) can be used for 6DOF tracking. In some examples, handheld controller 400B can include a camera as described above, and wearable head device 400A can include an optical target for optical tracking in conjunction with the camera. In some examples, the wearable head device 400A and the handheld controller 400B each include a set of three orthogonally oriented solenoids for wirelessly transmitting and receiving three distinct signals. used for By measuring the relative magnitudes of the three distinct signals received within each of the coils used to receive, the 6DOF of wearable head device 400A relative to handheld controller 400B can be determined. Additionally, the 6DOF totem subsystem 404A can include an inertial measurement unit (IMU) that is useful for providing improved accuracy and/or more timely information regarding high speed movement of the handheld controller 400B. .

In some embodiments, for example, to compensate for movement of wearable head device 400A relative to coordinate system 108, coordinates are inertially moved from a local coordinate space (eg, a coordinate space fixed relative to wearable head device 400A). It may be necessary to transform to a coordinate space (eg, a coordinate space that is fixed with respect to the real environment). For example, such a transformation may cause the display of wearable head device 400A to move the virtual object to its expected position and orientation relative to the real environment, rather than a fixed position and orientation on the display (e.g., the same position in the lower right corner of the display). (e.g., a virtual person seated in a real chair facing forward, regardless of the position and orientation of the wearable head device), the virtual object being present in the real environment (and, e.g., the wearable head device It may be necessary to preserve the illusion that as 400A translates and rotates, it does not appear unnaturally positioned in the real environment). In some embodiments, a compensating transformation between coordinate spaces uses SLAM and/or visual odometry procedures to determine the transformation of wearable head device 400A with respect to coordinate system 108 from images from depth camera 444. can be determined by processing In the example shown in FIG. 4, depth camera 444 may be coupled to SLAM/visual odometry block 406 and provide images to block 406 . The SLAM/visual odometry block 406 implementation processes this image, and then the user's head, which can be used to identify transformations between the head coordinate space and another coordinate space (eg, the inertial coordinate space). A processor can be included that is configured to determine the position and orientation of the portion. Similarly, in some embodiments, additional sources of information regarding the user's head pose and location are obtained from IMU 409 . Information from IMU 409 can be combined with information from SLAM/visual odometry block 406 to provide improved accuracy and/or more timely information regarding fast adjustment of the user's head pose and position.

In some examples, depth camera 444 can provide 3D images to hand gesture tracker 411, which can be implemented within the processor of wearable head device 400A. Hand gesture tracker 411 may, for example, identify a user's hand gestures by matching 3D images received from depth camera 444 to stored patterns representing hand gestures. Other suitable techniques for identifying user hand gestures will also become apparent.

In some embodiments, one or more of the processors 416 may receive data from the wearable head device's 6DOF headgear subsystem 404B, the IMU 409, the SLAM/visual odometry block 406, the depth camera 444, and/or the hand gesture tracker 411. may be configured to receive data from Processor 416 can also send control signals to and receive control signals from 6DOF totem system 404A. Processor 416 may be wirelessly coupled to 6DOF totem system 404A, such as in embodiments where handheld controller 400B is not tethered. Processor 416 may also communicate with additional components such as audio/visual content memory 418 , graphical processing unit (GPU) 420 , and/or digital signal processor (DSP) audio spatializer 422 . DSP audio spatializer 422 may be coupled to head related transfer function (HRTF) memory 425 . The GPU 420 may include a left channel output coupled to a left image-modulated light source 424 and a right-channel output coupled to a right image-modulated light source 426 . GPU 420 may output stereoscopic image data to image-wise modulated light sources 424, 426, for example, as described above with respect to FIGS. 2A-2D. DSP audio spatializer 422 may output audio to left speaker 412 and/or right speaker 414 . DSP audio spatializer 422 may receive input from processor 419 indicating a directional vector from the user to the virtual sound source (eg, which may be moved by the user via handheld controller 320). Based on the direction vector, DSP audio spatializer 422 can determine the corresponding HRTF (eg, by accessing the HRTF or by interpolating multiple HRTFs). DSP audio spatializer 422 may then apply the determined HRTF to an audio signal, such as the audio signal corresponding to the virtual sound produced by the virtual object. This is done by incorporating the user's relative position and orientation to the virtual sound within the mixed reality environment, i.e., matching the user's expectations of what the virtual sound would sound like if it were a real sound within a real environment. By presenting sounds, the believability and realism of virtual sounds can be improved.

In some embodiments, such as shown in FIG. 4, one or more of processor 416, GPU 420, DSP audio spatializer 422, HRTF memory 425, and audio/visual content memory 418 may: It may be included within auxiliary unit 400C (which may correspond to auxiliary unit 320 described above). Auxiliary unit 400C may include a battery 427 to power its components and/or provide power to wearable head device 400A or handheld controller 400B. Including such components in an auxiliary unit, which can be mounted on the user's waist, can limit the size and weight of the wearable head device 400A, which in turn reduces the user's head and neck. fatigue can be reduced.

Although FIG. 4 presents elements corresponding to various components of an exemplary mixed reality system, various other suitable arrangements of these components will be apparent to those skilled in the art. For example, elements presented in FIG. 4 as associated with auxiliary unit 400C may instead be associated with wearable head device 400A or handheld controller 400B. Additionally, some mixed reality systems may omit the handheld controller 400B or auxiliary unit 400C entirely. Such changes and modifications are to be understood as included within the scope of the disclosed embodiments.

delayed audio tracking

MR systems can be well positioned to utilize sensing and/or computation to provide an immersive audio experience. In particular, MR systems can provide unique ways to spatialize sound and immerse users within the MRE. The MR system can include speakers for presenting audio signals to the user, as described above with respect to speakers 412 and 414 . MR systems can determine audio signals and play them back based on a virtual environment (eg, MRE). For example, an audio signal can adopt certain characteristics depending on the location within the virtual environment (eg, the origin of the sound within the virtual environment) and the location of the user within the virtual environment. Similarly, an audio signal can employ audio characteristics that simulate the effect of sound traveling at a certain speed or with a certain orientation within the virtual environment. These characteristics can include placement within a stereo sound field. Some audio systems (eg, headphones) split the soundtrack into one or more channels and present the audio as originating from different locations. For example, headphones may utilize two channels, one channel for each ear of the user. If the soundtrack involves a virtual object moving across the screen (e.g., an airplane flying across the screen in a movie), the accompanying sound (e.g., engine noise) may be heard from the user's left side. It may be suggested to move to the right. Spatialized audio adds immersion to the virtual experience because the audio simulates how a person perceives real objects moving through the real world.

Some audio systems may suffer from limitations in their ability to provide immersive spatialized audio. For example, some headphone systems may present sound within a stereo sound field by separately presenting left and right audio channels to the user's left and right ears. However, without knowledge of the location (eg, position and/or orientation) of the user's head, the sound may sound statically fixed relative to the user's head. For example, sound presented to the user's left ear through the left channel is presented to the user's left ear regardless of whether the user turns his or her head and moves it forward, backward, sideways, etc. can continue to be This static behavior may not be desirable for MR systems because it may not match the user's expectations of how sound behaves dynamically in the real environment. For example, with a sound source at a fixed position, in a real environment a listener is emitted by that source and heard by the listener's left and right ears, the way the user moves and rotates relative to the position of the sound source. would be expected to be larger or smaller, or exhibit other dynamic audio characteristics (eg, Doppler effect). For example, if a static sound source is initially located on the user's left side, the sound emitted by that source may be predominant in the user's left ear compared to the user's right ear. However, if the user rotates 180 degrees so that the sound source is now located on the user's right side, the user would expect the sound to predominate in the user's right ear. Similarly, while the user is moving, the sound source may continually appear to change location relative to the user (e.g., slight positional changes may affect the volume detected at each ear). can result in perceptible changes). In a virtual or mixed reality environment, a user's perception of placement and immersion can be enhanced when sound behaves according to the user's expectations based on real-world audio experiences. In addition, users can utilize realistic audio cues to identify sound sources and place them in the environment.

MR systems (eg, MR systems 112, 200) may improve the immersion of spatialized audio by adapting to real-world audio behavior. For example, an MR system may utilize one or more cameras and/or one or more inertial measurement unit sensors of the MR system to perform SLAM calculations. Using SLAM techniques, the MR system may build a three-dimensional map of its surroundings and/or identify the location of the MR system within the surroundings. In some embodiments, the MR system may utilize SLAM to estimate head pose, which is information about the position of the user's head in three-dimensional space (e.g., location and/or or orientation). In some embodiments, the MR system may utilize one or more coordinate frames to identify the location of the object and/or the MR system in "absolute" sensing (e.g., the location of the virtual object). Locations may simply be tied to real locations in the real environment instead of being locked to the MR system or screen).

FIG. 5 illustrates an example of mixed reality spatialized audio, according to some embodiments. In some embodiments, the MR system uses SLAM techniques to fix one or more virtual objects such that instead of being fixed to the user, the virtual object is fixed to the environment. 504a and 504b may be located within the MRE. In some embodiments, virtual objects 504a and 504b can be configured to be sources of sound. Virtual objects 504a and/or 504b may be visible to user 502 (eg, as a virtual guitar), or virtual objects 504a and/or 504b may not be visible to the user (eg, sound from there). is emitted, as invisible). Using SLAM techniques, the MR system can place multiple virtual sound sources (eg, virtual objects 504a and/or 504b) around the user 502 to present spatialized audio. As user 502 rotates its head, user 502 may be able to perceive the location of virtual objects 504a and 504b (e.g., virtual object 504a may be visible when user 502 is in a first orientation). , is larger and smaller when user 502 is in the second orientation). This approach can have the advantage of allowing the user 502 to perceive dynamic changes in spatialization based on the user's 502 movements. This may create a more immersive audio experience than fixed sounds that do not match the user's 502 location.

However, in some embodiments, the exemplary approach shown in FIG. 5 may suffer from several disadvantages. In some applications, such as composed musical scores, sound designers may wish to limit the extent to which sounds exhibit spatialization behavior. Moreover, in some situations, spatialized audio can lead to harsh or unpleasant results. For example, fixing the virtual object 504b relative to its position within the MRE means that the sound emitted from the virtual object 504b may be louder than intended when the user 502 approaches the virtual object 504b. can. If virtual object 504b corresponds to the sound of a cello and is part of a virtual orchestra, the orchestral sound may be heard distorted by user 502 if user 502 stands too close to virtual object 504b. It may not be desirable to allow a user (eg, user 502) to walk too close to a sound source (eg, virtual object 504b) as it may deviate from the designed experience. For example, an overly loud sound on a virtual cello can dampen the sound from a virtual violin.

In addition to possible deviations from the designed experience, allowing the user to approach the virtual sound source may be particularly useful if the user's location nearly overlaps the source's location, or if the user's head is In extreme cases, such as fast moving or rotating relative to the sound source, it can confuse or confuse the user. In some embodiments, virtual object 504b may be non-visual from which sound is emitted. When user 502 approaches virtual object 504b, user 502 may perceive sound as clearly emanating from an invisible point of view. This may be the case, for example, if the sound attracts unwanted attention to the virtual object 504b (eg, if the virtual object 504b is configured to be invisible to avoid attracting the user's attention). Not desirable. In some embodiments, the intended central focus for the user may be the visual and/or narrated story, and the spatialized audio enhances the user's immersion in the visual and/or narrated story. may be used to allow For example, the MR system may present the user with a three-dimensional "movie" in which the user may walk around and observe characters and/or objects from different perspectives. In such applications, it can be disconcerting for the user to perceive non-viewpoints located within the mixed reality scene from which the sound is emitted. For example, in a battle scene it may not be desirable to allow the user to approach the point where an invisible guitar track is playing. Sound designers and story writers may desire to obtain additional control over the spatialized audio experience in order to preserve the intended narration. Therefore, it may be desirable to develop additional methods of providing immersive spatialized audio. For example, it may be desirable to allow audio designers to create custom audio behaviors that can be associated with sounds on an individual basis (eg, controlled by a script executed by a script engine). In some cases, default audio behaviors can be applied unless overridden by custom audio behaviors. In some cases, custom audio behavior can involve manipulating the origin of sounds to produce a desired audio experience.

6A-6C illustrate examples of mixed reality spatialized audio, according to some embodiments. Spatialized audio, like persistent visual content, can create a believable three-dimensional MRE (eg, MRE150) experience. As the user roams the real environment (e.g., real environment 100), the user behaves like a real object (e.g., persistent virtual content appears larger as the user approaches it and moves away from it). You can expect to see persistent virtual content that gets smaller as you move). Similarly, a user may expect a sound source to behave as if it were in the real environment while the user moves around (e.g., a sound source may sound louder as the user gets closer to it). , may sound softer as the user moves away). In some embodiments, immersive spatialized audio can be controlled by manipulating the sound source relative to the user's head, for example, through a "delayed follow" effect. For example, one or more sound sources may be spaced around the user's head and/or tied thereto at a first location. In a first location, one or more sound sources may be located at a designated location, which the sound sources are intended to produce a particular audio experience (e.g., developer or audio by the designer). The position of the sound source may correspond to the origin of the sound source, eg, the coordinates in the MRE from which the sound appears to originate. The sound source origin may be expressed as an offset (eg, vector offset) from the user's head (or other listener position). That is, presenting a sound to a user can include determining an offset from the user's head and applying the offset to the user's head to arrive at the sound source origin. A first position of the user's head at a first time is determined, for example, by one or more sensors of the wearable head device as described above (eg, with respect to wearable head device 401A). can A second position of the user's head at a second later time can then be determined. The difference between the first position and the second position of the head can be used to manipulate the audio signal. For example, in some cases, when the user moves their head to a second position, the one or more sound sources are spaced around and/or thereabouts of the user's head. can be instructed to "follow" movement of the head so that it can deviate from its specified position (e.g., spaced around the user's head and/or there may move/change relative to the user's head, and the sound source is no longer spaced around and/or tied to the user's head; may not be located at that specified location). This manipulation of the sound source can be implemented, for example, by moving the sound source origin from the first position by an amount less than the difference between the first and second positions of the head. . In some embodiments, the specified position may remain fixed relative to the user's head position, but the corresponding virtual sound source is "elasticly" tied to the user's head position. may be traced behind the corresponding specified location. In some embodiments, the sound source is spaced around and/or tied to the user's head at some point after the user's head reaches the second position, the designated It may return to a location (eg, the same location intended to produce a particular audio experience). Other manipulations of the sound source origin are also contemplated and within the scope of the present disclosure, such as determining the origin based on the difference between a first head position and a second head position. More generally, custom audio dynamics can be created by manipulating the source origin relative to the user's head or some other object in the MRE, including moving objects. For example, the sound source origin is defined as a function of the user's head position and orientation, or as a function of changes in head position or orientation over time or accumulation (e.g., a function of the integral or derivative of head position or orientation). can be Such functions can be used for creative effects, such as simulating sound traveling at a particular speed or in a particular direction. For example, the velocity of the user's head movement can be determined (e.g., the derivative of head movement determined by one or more sensors of the wearable head device as described above). ), the sound can be presented as if the sound origin were traveling at its same speed (or different speeds based on the speed of the head). As another example, changes in the orientation of the user's head can be determined, such as via one or more sensors of the wearable head device as described above, sound, It can be presented as if the sound origin moves with orientation based on changes in the user's head orientation. Representing the sound origin as a function of the user's head position or orientation can also be adapted to smoothly handle situations that would otherwise cause undesirable audio results. For example, by defining a function that limits the extent to which sound sources move relative to the user's head, extreme or undesirable audio effects from those sound sources may be limited or avoided. This can be implemented, for example, by establishing a threshold rate of change of the user's head position. That is, if the rate of change exceeds a threshold, the change in the position of the sound source origin can be appropriately limited (e.g., if the threshold is exceeded, the origin is set to the first coordinate; , by setting the origin to different coordinates). As another example to avoid undesirable audio effects, the sound source origin can be configured to always remain at least a minimum distance from the user. For example, if the magnitude of the offset between the sound source origin and the user's head is below a minimum threshold, the origin can be relocated to an alternate location that is at least the minimum distance from the user's head. .

As shown in FIG. 6A, in some embodiments, virtual objects 604a and/or 604b may be spaced around center 602 and/or bound thereto. Virtual objects 604a and/or 604b may be visible (eg, displayed to the user) or invisible (eg, not displayed to the user). In some embodiments, virtual objects 604a and/or 604b may not interact with other virtual objects. For example, virtual objects 604a and/or 604b may not collide with other virtual objects. Virtual objects 604a and/or 604b may not reflect/absorb/transmit light from other virtual objects, and/or virtual objects 604a and/or 604b may reflect/reflect sound from other virtual objects. It does not have to be absorbed/transmitted. In some embodiments, virtual objects 604a and/or 604b may interact with other virtual objects.

In some embodiments, virtual objects 604a and/or 604b may be associated with one or more sound sources. In some cases, each virtual object may correspond to one sound source. For example, virtual objects 604a and/or 604b may be configured to virtually emit sound from their location within the MRE. Configuring the sound source so that it can be perceived as emanating from a location can be done using any suitable method. For example, head-related transfer functions (“HRTFs”) can be used to simulate sounds emanating from a particular location. In some embodiments, a generic HRTF can be used. In some embodiments, for example, one or more microphones around the user's ear (e.g., one or more microphones in an MR system) determine one or more user-specific HRTFs. can be used to In some embodiments, the distance between the user and the virtual sound source is simulated using suitable methods (e.g., sound pressure attenuation, high frequency attenuation, direct and reverberant sound mixing, motion parallax, etc.) may be In some embodiments, virtual objects 604a and/or 604b may be configured to emit sound as a point source. In some embodiments, virtual objects 604a and/or 604b may include physical three-dimensional models of sound sources, and sounds may be generated by modeling interactions with sound sources. For example, virtual object 604a may include a virtual guitar, including a wood body, strings, tuning pegs, and the like. Sounds may be generated by modeling the plucking of one or more strings and how the action interacts with other components of the virtual guitar.

In some embodiments, virtual objects 604a and/or 604b may emit sound omnidirectionally. In some embodiments, virtual objects 604a and/or 604b may emit sound directionally. In some embodiments, virtual objects 604a and/or 604b may be configured to include sound sources, and each sound source may include a musical stem. In some embodiments, a musical stem may be an arbitrary subset of the overall sound of music. For example, or an orchestral soundtrack may include violin stems, cello stems, bass stems, trumpet stems, tympani stems, and the like. In some embodiments, channels of a multi-channel soundtrack can be represented as stems. For example, a two channel soundtrack may include a left stem and a right stem. In some embodiments, a single track of the mix may be represented as a stem. In some embodiments, a musical soundtrack may be split into stems according to frequency bands. Stems can represent any arbitrary subset of the overall sound.

In some embodiments, virtual objects 604a and/or 604b may be associated with one or more objects (eg, center 602 and/or vector 606). For example, virtual object 604a may be assigned to designated location 608a. In some embodiments, designated location 608a can be a fixed point relative to vector 606 and/or center 602 . In some embodiments, virtual object 604b may be assigned to designated location 608b. In some embodiments, designated location 608b can be a fixed point with respect to vector 606 and/or center 602 . Center 602 can be a point and/or a three-dimensional object. In some embodiments, virtual objects 604a and/or 604b may be attached to points of the three-dimensional object (eg, the center point of the three-dimensional object or points on its surface). In some embodiments, center 602 may correspond to any suitable point (eg, the center of the user's head). The center of the user's head may be estimated using the center of the head-mounted MR system (which may have known dimensions) and average head dimensions, or using other suitable methods. good. In some embodiments, virtual objects 604a and/or 604b may be associated with a directional indicator (eg, vector 606). In some embodiments, virtual object 604a and/or 604b can be placed at a specified location, including and/or defined by its location relative to center 602 and/or vector 606. (eg, using a spherical coordinate system). In some embodiments, virtual objects 604a and/or 604b may deviate from their designated positions when center 602 and/or vector 606 change position (eg, location and/or orientation). . In some embodiments, the virtual objects 604a and/or 604b may continue for a predetermined time period (e.g., , 5 seconds) and then return to its designated position.

As shown in FIG. 6B, vector 606 may change direction. In some embodiments, designated positions 608a and/or 608b may move correspondingly. For example, designated positions 608a and/or 608b may be the same positions relative to center 602 and/or vector 606 in FIG. 6B as in FIG. 6A. In some embodiments, virtual objects 604a and/or 604b may follow movements of designated positions 608a and/or 608b. For example, as vector 606 moves from a first position in FIG. 6A to a second position in FIG. In both 6A and 6B, it may remain in the same position (even though designated positions 608a and/or 608b move). In some embodiments, virtual objects 604a and/or 604b may begin moving after vector 606 and/or center 602 begin moving and/or moving. In some embodiments, virtual objects 604a and/or 604b may start moving after vector 606 and/or center 602 have stopped moving, eg, for a predetermined period of time. 6C, virtual objects 604a and/or 604b may return to their designated positions relative to vector 606 and/or center 602. In FIG. For example, virtual objects 604a and/or 604b may occupy the same positions relative to vector 606 and/or center 602 in FIG. 6C as in FIG. 6A.

A virtual object 604a and/or 604b may deviate from its designated position 608a and/or 608b for a period of time. In some embodiments, as vector 606 and/or center 602 change direction, virtual objects 604a and/or 604b "trace" the path of movement of designated positions 608a and/or 608b, respectively. may In some embodiments, virtual objects 604a and/or 604b may follow an interpolated path from their current position to designated positions 608a and/or 608b, respectively. In some embodiments, virtual objects 604a and/or 604b move to their designated positions once center 602 and/or vector 606 have completely stopped acceleration and/or movement (eg, linear and/or angular acceleration). You may return to the position where For example, center 602 may remain a stationary point and vector 606 may rotate about center 602 at constant velocity (eg, because the user rotates his or her head). After some period of time, virtual objects 604a and/or 604b may return to their designated positions despite the fact that vector 606 remains moving at a constant speed. Similarly, in some embodiments, center 602 may move at a constant velocity (and vector 606 may remain stationary or may also move at constant velocity), Virtual objects 604a and/or 604b may return to their designated positions after the initial acceleration ceases. In some embodiments, virtual objects 604a and/or 604b may return to their designated positions once center 602 and/or vector 606 stop moving. For example, if the user's head is rotating at a constant speed, virtual objects 604a and/or 604b may continue to "lagging" from their designated position until the user stops spinning their head. good. In some embodiments, virtual objects 604a and/or 604b may return to their designated positions once center 602 and/or vector 606 stop accelerating. For example, if the user's head begins to rotate and then continues to rotate at a constant speed, virtual objects 604a and/or 604b will first lag from their designated position, then the user's head will After reaching a constant velocity (eg, over a threshold time period), the specified position may be reached.

In some embodiments, one or more sound sources may move as if they were "elasticly" tied to the user's head. For example, as a user rotates their head from a first position to a second position, one or more sound sources may not rotate at the same angular velocity as the user's head. In some embodiments, the one or more sound sources start rotating at a slower angular velocity than the user's head, accelerate the angular velocity, and as they approach their initial position relative to the user's head, Angular velocity may be reduced. The rate of change of angular velocity may be capped, for example, at a level preset by the sound designer. This is both to allow the sound source to move very quickly (which can lead to undesirable audio effects as explained above) and to prevent the sound source from moving at all (spatialized audio). A balance can be struck between

In some embodiments, having one or more spatialized sources perform delayed tracking can have several advantages. For example, allowing the user to deviate in relative position from the spatialized sound source can allow the user to perceive differences in sound. The user will notice that the spatialized sound becomes slightly quieter as the user turns away from the spatialized sound, which may enhance the user's sense of immersion within the MRE. In some embodiments, delay tracking can also preserve the desired audio experience. For example, the user may be prevented from unintentionally distorting the audio experience by approaching and staying very close to the sound source. If a sound source is statically placed relative to the environment, the user may be close to the sound source, and the spatialization device may undesirably suppress other sound sources excessively as a result of the user's proximity. (especially as the distance between the user and the sound source approaches zero). In some embodiments, delay tracking moves the sound source to a set position relative to the user after some delay so that the user may experience enhanced spatialization without compromising the overall audio effect. (eg, because each sound source can generally be maintained at a desired distance from each other and/or from the user).

In some embodiments, virtual objects 604a and/or 604b can have dynamically specified positions. For example, the specified position 608a may move (eg, follow the trajectory of the user's head, or be closer to and/or away from the user's head) even though the center 602 and vector 606 remain stationary. further apart). In some embodiments, the dynamically specified position can be determined relative to a center and/or vector (e.g., a moving center and/or vector), and the virtual object Positions can be moved in a delayed-following manner (eg, by tracing movement of specified positions and/or interpolating paths).

In some embodiments, the virtual objects 604a and/or 604b can be placed at their designated locations using an asset design tool for the game engine (eg, Unity). In some embodiments, virtual objects 604a and/or 604b may include game engine objects, which may be placed within a three-dimensional environment (eg, an MRE supported by a game engine). In some embodiments, virtual objects 604a and/or 604b may be components of parent objects. In some embodiments, the parent object may include parameters such as corresponding centers and/or vectors for placing the virtual object at the specified location. In some embodiments, the parent object may specify parameters such as the speed at which the virtual object should return to its specified position and/or the conditions under which the virtual object should return to its specified position (e.g., constant speed or no motion). A delay tracking parameter may also be included. In some embodiments, the parent object includes parameters regarding the speed at which the virtual object tracks its specified position (eg, whether the virtual object should move, accelerate, and/or decelerate at a constant speed). It's okay. In some embodiments, the parent object may include parameters for determining the path that the virtual object can follow from its current position to its specified position (e.g., using linear and/or exponential interpolation). Use). In some embodiments, a virtual object (eg, virtual objects 604a and 604b) may include such parameters of its own.

In some embodiments, the game engine may maintain the properties of some or all of virtual objects 604a and 604b (eg, current and/or designated locations of virtual objects 604a and 604b). In some embodiments, the current locations of virtual objects 604a and 604b (e.g., through the locations and/or properties of parent objects or directly, the locations and/or properties of virtual objects 604 and 604b) are spatialized and /or passed to a rendering engine. For example, the spatialization and/or rendering engine may receive sounds emanating from the virtual object 604a and the current position of the virtual object 604a. A spatialization and/or rendering engine may process the input and produce output, which may include spatialized sound, which may be configured to perceive sound as originating from the location of virtual object 604a. The spatialization and/or rendering engine may use any suitable technique to render the spatialized sound, including but not limited to head-related transfer functions and/or distance attenuation techniques.

In some embodiments, a spatialization and/or rendering engine may receive the data structure and render the delayed-tracking spatialized sound. For example, the delayed tracking data structure may include a data format along with parameters and/or metadata and/or delayed tracking parameters related to position relative to head pose. In some embodiments, an application running on the MR system may send one or more delay-tracking data structures to the spatialization and/or rendering engine to render the delay-tracking spatialized sound.

In some embodiments, the soundtrack may be processed into a delay-following data structure. For example, a 5.1 channel soundtrack may be split into six stems, and each stem may be assigned to one or more virtual objects (eg, virtual objects 604a and 604b). Each stem/virtual object may be placed in a pre-configured orientation for 5.1 channel surround sound (e.g., the center speaker stem is positioned directly in front of the user's face at approximately 20 feet in front of the user). may be placed in). In some embodiments, the delay-following data structure may then be used by the spatialization and/or rendering engine to render the delay-following spatialized sound.

In some embodiments, the delayed-following spatialized sound may be rendered for more than one user. For example, a set of virtual objects configured to surround a first user may be perceptible to a second user. A second user may observe the virtual object/sound source following the first user in a delayed manner. In some embodiments, a set of virtual objects/sound sources may be configured to surround more than one user. For example, the center point may be calculated as the center point between the first user's head and the second user's head. The vectors may be computed as the mean vector between the vectors representing the directions facing each user. One or more virtual objects/sound sources may be placed relative to dynamically calculated center points and/or vectors.

Although two virtual objects are shown in FIGS. 6A-6C, it is contemplated that any number of virtual objects and/or sound sources may be used. In some embodiments, each virtual object and/or sound source may have its own distinct parameters. Center points/objects and vectors are used to position the position virtual object, but any suitable coordinate system (eg, Cartesian, spherical, etc.) may also be used.

Systems, methods, and computer-readable media are disclosed. According to some embodiments, the system includes a wearable head device having a speaker and one or more sensors, and a user's head at a first time based on the one or more sensors. determining a first position; determining a second position of the user's head at a second time after the first time based on one or more sensors; determining an audio signal based on a difference between the position of and a second position; and presenting the audio signal to a user via a speaker. , one or more processors, wherein determining the audio signal includes determining an origin of the audio signal within the virtual environment, and presenting the audio signal to the user comprises: Presenting the audio signal as it occurs, wherein determining the origin of the audio signal includes applying an offset to the position of the user's head. In some examples, determining the origin of the audio signal further includes determining the origin of the audio signal based on a rate of change of the position of the user's head. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the rate of change exceeds the threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that there is no origin. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the magnitude of the offset is below a threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that is not below the threshold. In some examples, determining the audio signal further includes determining a velocity within the virtual environment, and presenting the audio signal to the user further determines whether the origin moves at the determined velocity. including presenting an audio signal. In some examples, determining the velocity includes determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. In some examples, the offset is determined based on the first position of the user's head.

According to some embodiments, a method of presenting audio to a user of a wearable head device includes: based on one or more sensors of the wearable head device, a first audio signal of the user's head at a first time; determining a second position of the user's head at a second time after the first time based on one or more sensors; determining the audio signal based on the difference between the position and the second location; and presenting the audio signal to the user via a speaker of the wearable head device. includes determining an origin of the audio signal within the virtual environment; presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin; Determining the origin includes applying an offset to the position of the user's head. In some examples, determining the origin of the audio signal further includes determining the origin of the audio signal based on a rate of change of the position of the user's head. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the rate of change exceeds the threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that there is no origin. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the magnitude of the offset is below a threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that is not below the threshold. In some examples, determining the audio signal further includes determining a velocity within the virtual environment, and presenting the audio signal to the user further determines whether the origin moves at the determined velocity. including presenting an audio signal. In some examples, determining the velocity includes determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. In some examples, the offset is determined based on the first position of the user's head.

According to some embodiments, a non-transitory computer-readable medium presents audio to a user of a wearable head device to the one or more processors when executed by the one or more processors. storing instructions that cause a method to be performed, the method determining a first position of the user's head at a first time based on one or more sensors of the wearable head device; determining a second position of the user's head at a second time after the first time based on one or more sensors; and between the first position and the second position; and presenting the audio signal to the user via a speaker of the wearable head device, wherein determining the audio signal is based on the difference between the audio signal in the virtual environment presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin; determining the origin of the audio signal includes determining the offset to the position of the user's head. In some examples, determining the origin of the audio signal further includes determining the origin of the audio signal based on a rate of change of the position of the user's head. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the rate of change exceeds the threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that there is no origin. In some embodiments, determining the origin of the audio signal further comprises determining that the origin comprises the first origin according to determining that the magnitude of the offset is below a threshold; determining that the origin comprises a second origin that is different from the first origin, according to the determination that is not below the threshold. In some examples, determining the audio signal further includes determining a velocity within the virtual environment, and presenting the audio signal to the user further determines whether the origin moves at the determined velocity. including presenting an audio signal. In some examples, determining the velocity includes determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. In some examples, the offset is determined based on the first position of the user's head.

Although the disclosed embodiments have been fully described with reference to the accompanying drawings, it should be noted that various changes and modifications will become apparent to those skilled in the art. For example, elements of one or more implementations may be combined, deleted, modified, or supplemented to form further implementations. Such changes and modifications are to be understood as included within the scope of the disclosed embodiments as defined by the appended claims.

Claims (20)

a system,
a wearable head device having a speaker and one or more sensors;
one or more processors,
determining a first position of the user's head at a first time based on the one or more sensors;
determining a second position of the user's head at a second time after the first time based on the one or more sensors;
determining an audio signal based on the difference between the first position and the second position;
presenting the audio signal to the user via the speaker; and one or more processors configured to perform a method comprising:
determining the audio signal includes determining an origin of the audio signal within a virtual environment;
presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin;
The system, wherein determining the origin of the audio signal includes applying an offset to a position of the user's head. 2. The system of claim 1, wherein determining the origin of the audio signal further comprises determining the origin of the audio signal based on a rate of change of the user's head position. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the rate of change exceeds a threshold;
3. The system of claim 2, comprising determining that the origin comprises a second origin different from the first origin, following a determination that the rate of change does not exceed the threshold. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the magnitude of the offset is below a threshold;
determining that the origin comprises a second origin that is different from the first origin, following a determination that the magnitude of the offset does not fall below the threshold. determining the audio signal further includes determining velocity within the virtual environment;
presenting the audio signal to the user further comprises presenting the audio signal as if the starting point were moving at the determined velocity;
The system of claim 1. 6. Determining the velocity comprises determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. The system described in . 2. The system of claim 1, wherein the offset is determined based on a first position of the user's head. A method of presenting audio to a user of a wearable head device, comprising:
determining a first position of the user's head at a first time based on one or more sensors of the wearable head device;
determining a second position of the user's head at a second time after the first time based on the one or more sensors;
determining an audio signal based on the difference between the first position and the second position;
presenting the audio signal to the user via a speaker of the wearable head device;
determining the audio signal includes determining an origin of the audio signal within a virtual environment;
presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin;
A method, wherein determining the origin of the audio signal includes applying an offset to a position of the user's head. 9. The method of claim 8, wherein determining the origin of the audio signal further comprises determining the origin of the audio signal based on a rate of change of the user's head position. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the rate of change exceeds a threshold;
10. The method of claim 9, comprising determining that the origin comprises a second origin different from the first origin, following a determination that the rate of change does not exceed the threshold. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the magnitude of the offset is below a threshold;
9. The method of claim 8, comprising determining that the origin comprises a second origin that is different from the first origin, following a determination that the magnitude of the offset does not fall below the threshold. determining the audio signal further includes determining velocity within the virtual environment;
presenting the audio signal to the user further comprises presenting the audio signal as if the starting point were moving at the determined velocity;
9. The method of claim 8. 13. Determining the velocity comprises determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. The method described in . 9. The method of claim 8, wherein the offset is determined based on a first position of the user's head. A non-transitory computer-readable medium, said non-transitory computer-readable medium storing instructions which, when executed by one or more processors, cause said one or more to implement a method of presenting audio to a user of a wearable head device, the method comprising:
determining a first position of the user's head at a first time based on one or more sensors of the wearable head device;
determining a second position of the user's head at a second time after the first time based on the one or more sensors;
determining an audio signal based on the difference between the first position and the second position;
presenting the audio signal to the user via a speaker of the wearable head device;
determining the audio signal includes determining an origin of the audio signal within a virtual environment;
presenting the audio signal to the user includes presenting the audio signal as if it originated from the determined origin;
determining the origin of the audio signal includes applying an offset to a position of the user's head;
non-transitory computer-readable medium; 16. The non-transient computer readable of claim 15, wherein determining the origin of the audio signal further comprises determining the origin of the audio signal based on a rate of change of the user's head position. medium. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the rate of change exceeds a threshold;
determining that the origin comprises a second origin that is different from the first origin, following a determination that the rate of change does not exceed the threshold. readable medium. Determining the origin of the audio signal further comprises:
Determining that the origin comprises a first origin according to determining that the magnitude of the offset is below a threshold;
16. The non-transitory method of claim 15, comprising determining that the origin comprises a second origin different from the first origin, following a determination that the magnitude of the offset does not fall below the threshold. sexual computer readable medium. determining the audio signal further includes determining velocity within the virtual environment;
presenting the audio signal to the user further comprises presenting the audio signal as if the starting point were moving at the determined velocity;
16. The non-transitory computer-readable medium of claim 15. 20. Determining the velocity comprises determining the velocity based on a difference between a first position of the user's head and a second position of the user's head. 3. The non-transitory computer-readable medium as described in .

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