Today the U.S. Patent and Trademark Office officially granted Apple a patent that relates to tracking devices worn by a user, and, more particularly, to wrist tracking devices for detection by Apple's future head-mountable devices.

A head-mountable device can be worn by a user to display visual information within the field of view of the user. The head-mountable device can be used as a virtual reality (VR) system, an augmented reality (AR) system, and/or a mixed reality (MR) system. A user may observe outputs provided by the head-mountable device, such as visual information provided on a display. The display can optionally allow a user to observe an environment outside of the head-mountable device. Other outputs provided by the head-mountable device can include audio output and/or haptic feedback. A user may further interact with the head-mountable device by providing inputs for processing by one or more components of the head-mountable device. For example, the user can provide tactile inputs, voice commands, and other inputs while the device is mounted to the user's head.

Head-mountable devices, such as head-mountable displays, headsets, visors, smartglasses, head-up display, etc., can perform a range of functions that are managed by the components (e.g., sensors, circuitry, and other hardware) included with the wearable device.

Head-mountable devices can be equipped with a wide range of outward and inward facing sensors. These sensors can recognize and track objects, surfaces, and user gestures such as hand and body movements. The functionality of such sensors can be limited by factors such as component cost, device size, device weight, heat generation, available computing power, and/or occlusion due to the device being in a specific location relative to other objects or users.

Head-mountable devices can collect data from and/or relating to a device and make certain determinations that aid the process of displaying a representation (e.g., virtual rendering) to the user. For example, an object can be provided with indicators that allow a head-mountable device to determine both an identity and a characteristic (e.g., position, orientation, distance, etc.) of the object.

By further example, the user's hands, arms, or other limbs can be recognizable by a head-mountable device by being attached to one or more tracking devices in a manner that maintains a fixed relative position and orientation between the user's hands and the corresponding tracking devices.

The head-mountable device can determine both an identity and a characteristic (e.g., position, orientation, distance, etc.) of the tracking devices, and therefor the hands. The information regarding the tracking devices and/or the hands can be used to produce a virtual representation of the hands or otherwise be used to receive and interpret gestures as user input.

Rather than requiring a head-mountable device to directly identify and analyze each hand independently, analysis of a tracking device worn by the user can provide sufficient constraints to determine characteristics of the hands, without requiring that the hands be independently analyzed. With such analysis, the speed and accuracy of object recognition, hand and body tracking, surface mapping, and/or digital reconstruction can be improved. The devices that facilitate such tracking can be worn in a variety or arrangements depending on whether the tracking is to be performed. As such, they can be compactly stored in a manner that allows them to be readily accessible for deployment.

Apple's patent FIG. 1 below illustrates a view of a head-mountable device and tracking devices on a user's wrists; FIG. 2 illustrates a perspective view of a watch and a wrist tracking device; FIG. 3 illustrates a top view of the watch and the wrist tracking device of FIG. 2 on wrists of a user.

Apple's patent FIG. 4 below illustrates a perspective view of a watch, a switchable tracking device, and a wrist tracking device; FIG. 5 illustrates a top view of the watch of FIG. 4 on a wrist of a user and the switchable tracking device and the wrist tracking device of FIG. 4 on another wrist of the user; FIG. 6 illustrates a top view of the watch and the switchable tracking device of FIG. 4 on a wrist of a user and the wrist tracking device of FIG. 4 on another wrist of the user; FIG. 7 illustrates a perspective view of a watch and a switchable tracking device.

The switchable tracking device indicators #450 can include features that are detectable by a head-mountable device or another external device. The switchable tracking device indicators can be used to identify the switchable tracking device #400 to a head-mountable device.

As shown in FIG. 4, the switchable tracking device indicators can be provided at different regions of the switchable tracking device. The switchable tracking device indicators can include one or more emitters that can produce an output, such as light, sound, electromagnetic radiation, and the like.

In some embodiments, the switchable tracking device indicators can include light emitters that emit light that is optically detectable by an external device. While one type of indicator is illustrated, it will be recognized that one or more of various kinds of indicators can be employed.

For example, indicators can include emitters, patterns, symbols, text (alpha and/or numeric), images, barcodes (e.g., Universal Product Code), QR codes, and the like. Such indicators may be formed as patterns of contrasting dark (e.g., black) and light (e.g., white) portions.

By further example, the switchable tracking device indicators can include ultraviolet-reflective ink and/or infrared-reflective ink. As such, the switchable tracking device indicators can provide identification capabilities without being noticeable by a user.

Apple's patent FIG. 10 below illustrates a block diagram of a system including a head-mountable device, a watch, a switchable tracking device, and a wrist tracking device.

Additionally, or alternatively, the head-mountable device can include one or more sensors #140. Such sensors can include an environmental sensor that detects one or more conditions in an environment of the head-mountable device. For example, an environmental sensor can include an imaging device, a thermal sensor, a proximity sensor, a motion sensor, a humidity sensor, a chemical sensor, a light sensor, and/or a UV sensor. An environmental sensor can be configured to sense substantially any type of characteristic such as, but not limited to, images, pressure, light, touch, force, temperature, position, motion, and so on.

For example, the environmental sensor may be a photodetector, a temperature sensor, a light or optical sensor, an atmospheric pressure sensor, a humidity sensor, a magnet, a gyroscope, an accelerometer, a chemical sensor, an ozone sensor, a particulate count sensor, and so on. The sensor can be used to sense ambient conditions in a neighboring environment.

For more details, review Apple's granted patent 11,175,734.