PATENT DOCUMENT

Publication Number: US-11810714-B2
Application Number: US-202117160430-A
Country: US
Kind Code: B2

Title: Headband for head-mounted device

Abstract:
A head-mounted device includes a device housing, a display device, an optical system, and a headband. The head-mounted device also includes a first headband connector that includes a headband-side connector portion that is connected to the headband at a first end of the headband and a device-side connector portion that is connected to the device housing. The first headband connector is movable between a disconnected position, in which the headband-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion. The first headband connector also includes paired magnetic components that are configured to attract the headband-side connector portion and the device-side connector portion to one another to urge the first headband connector to move to the connected position.

Claims:
What is claimed is: 
     
       1. A head-mounted device, comprising:
 a device housing; 
 a display device that is connected to the device housing to display content to a user as emitted light; 
 an optical system that is configured to direct the emitted light to eyes of the user; 
 a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head; and 
 a first headband connector that includes a headband-side connector portion that is connected to the headband at the first end of the headband and a device-side connector portion that is connected to the device housing, 
 wherein the first headband connector is movable between a disconnected position, in which the headband-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion, and 
 wherein the first headband connector includes paired magnetic components that are configured to attract the headband-side connector portion and the device-side connector portion to one another to urge the first headband connector to move to the connected position. 
 
     
     
       2. The head-mounted device of  claim 1 , wherein the paired magnetic components include a permanent magnet and a ferromagnetic structure. 
     
     
       3. The head-mounted device of  claim 1 , wherein the paired magnetic components include a first permanent magnet that is located on the headband-side connector portion and a second permanent magnet that is located on the device-side connector portion. 
     
     
       4. The head-mounted device of  claim 1 , wherein the first headband connector includes an electrical power connection. 
     
     
       5. The head-mounted device of  claim 1 , wherein the first headband connector includes a communications signal connection. 
     
     
       6. The head-mounted device of  claim 1 , further comprising:
 a second headband connector that includes a headband-side connector portion that is connected to the headband at the second end of the headband and a device-side connector portion that is connected to the device housing. 
 
     
     
       7. The head-mounted device of  claim 1 , further comprising:
 a second headband connector that is directly connected to the device housing and is non-releasable with respect to the device housing. 
 
     
     
       8. The head-mounted device of  claim 1 , further comprising:
 an additional headband connector that is located along the headband and is movable between a connected position and a disconnected position. 
 
     
     
       9. The head-mounted device of  claim 1 , wherein the paired magnetic components include an electromagnet that is operable to generate a magnetic attraction force and application of the magnetic attraction force ceases in response to determining that a current draw by the electromagnet is greater than a threshold value. 
     
     
       10. A head-mounted device, comprising:
 a device housing; 
 a display device that is connected to the device housing to display content to a user as emitted light; 
 an optical system that is configured to direct the emitted light to eyes of the user; 
 a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head; 
 a first headband connector that includes a headband-side connector portion that is connected to the headband at the first end of the headband and a device-side connector portion that is connected to the device housing, wherein the first headband connector includes an electromagnet, the first headband connector is movable between a disconnected position, in which the headband-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion; and 
 a release button that is operable to change operation of the electromagnet to cause the first headband connector to move from the connected position to the disconnected position. 
 
     
     
       11. The head-mounted device of  claim 10 , wherein the release button is located on the headband at a location that is spaced from the first headband connector. 
     
     
       12. The head-mounted device of  claim 10 , further comprising:
 a power source that is located on the headband and is operable to supply electrical power to the electromagnet. 
 
     
     
       13. The head-mounted device of  claim 10 , wherein the electromagnet is operable to apply a magnetic attraction force to maintain the first headband connector in the connected position. 
     
     
       14. The head-mounted device of  claim 13 , wherein the release button, when operated by the user, causes the electromagnet to cease application of the magnetic attraction force to cause the first headband connector to move from the connected position to the disconnected position. 
     
     
       15. The head-mounted device of  claim 10 , wherein the first headband connector includes paired magnetic components that are configured to maintain the first headband connector in the connected position when the electromagnet is not operated and the electromagnet is operable to apply a magnetic repulsion force to move the first headband connector from the connected position to the disconnected position when the electromagnet is operated. 
     
     
       16. The head-mounted device of  claim 15 , wherein the release button, when operated by the user, causes the electromagnet to apply the magnetic repulsion force to cause the first headband connector to move from the connected position to the disconnected position. 
     
     
       17. A head-mounted device, comprising:
 a device housing; 
 a display device that is connected to the device housing to display content to a user as emitted light; 
 an optical system that is configured to direct the emitted light to eyes of the user; 
 a headband that is configured to support the device housing with respect to the user&#39;s head; and 
 a headband adjustment device that is connected to the headband and includes adjuster portions, wherein the headband adjustment device is able to contract and expand a length of the headband by moving the adjuster portions with respect to one another. 
 
     
     
       18. The head-mounted device of  claim 17 , wherein the adjuster portions are connected to one another by connecting structures that allow adjacent ones of the adjuster portions to move toward each other and away from each other. 
     
     
       19. The head-mounted device of  claim 17 , wherein the headband adjustment device includes biasing structures that urge adjacent ones of the adjuster portions to move at least one of toward each other or away from each other. 
     
     
       20. The head-mounted device of  claim 17 , wherein a first pair of adjuster portions are related to one another by an electromagnetic device that is controllable to cause the first pair of adjuster portions to move at least one of toward each other or away from each other. 
     
     
       21. The head-mounted device of  claim 17 , further comprising:
 a sensor that outputs a signal that represents a magnitude of motion, wherein a magnitude of tension applied to the headband by the headband adjustment device is controlled according to the signal. 
 
     
     
       22. A head-mounted device, comprising:
 a device housing; 
 a display device that is connected to the device housing to display content to a user as emitted light; 
 an optical system that is configured to direct the emitted light to eyes of the user; 
 a headband that is configured to support the device housing with respect to the user&#39;s head; 
 an accessory component; and 
 an accessory adjustment device that is connected to the headband, supports the accessory component with respect to the headband, and includes a first end portion that is connected to the headband, a second end portion that is connected to the headband, an adjuster portion, and an electromagnetic device, wherein the electromagnetic device is operable to move the adjuster portion between the first end portion and the second end portion to change a location of the accessory component with respect to the headband. 
 
     
     
       23. The head-mounted device of  claim 22 , wherein the adjuster portion is connected to the first end portion and the second end portion by connecting structures that allow the adjuster portion to move between the first end portion and the second end portion. 
     
     
       24. The head-mounted device of  claim 22 , wherein the accessory component is a loudspeaker. 
     
     
       25. A wearable electronic device, comprising:
 a device housing; 
 a support that has a first end and a second end and is configured to secure the device housing with respect to a user; and 
 a first support connector that includes a support-side connector portion that is connected to the support at the first end of the support and a device-side connector portion that is connected to the device housing, 
 wherein the first support connector is movable between a disconnected position, in which the support-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the support-side connector portion is connected to the device-side connector portion, and 
 wherein the first support connector includes paired magnetic components that are configured to attract the support-side connector portion and the device-side connector portion to one another to urge the first support connector to move to the connected position. 
 
     
     
       26. The wearable electronic device of  claim 25 , wherein the paired magnetic components include a permanent magnet and a ferromagnetic structure. 
     
     
       27. The wearable electronic device of  claim 25 , wherein the paired magnetic components include a first permanent magnet that is located on the headband-side connector portion and a second permanent magnet that is located on the device-side connector portion. 
     
     
       28. The wearable electronic device of  claim 25 , wherein the paired magnetic components include an electromagnet. 
     
     
       29. The wearable electronic device of  claim 28 , wherein the electromagnet is operable to generate a magnetic attraction force to maintain the first support connector in the connected position, and application of the magnetic attraction force ceases in response to operation of a release button. 
     
     
       30. The wearable electronic device of  claim 28 , wherein the electromagnet is operable to generate a repulsion force in response to operation of a release button to cause the first support connector to move from the connected position to the disconnected position. 
     
     
       31. The wearable electronic device of  claim 28 , wherein the electromagnet is operable to generate a magnetic attraction force and application of the magnetic attraction force ceases in response to determining that a current draw by the electromagnet is greater than a threshold value. 
     
     
       32. The wearable electronic device of  claim 25 , wherein the first support connector includes an electrical power connection. 
     
     
       33. The wearable electronic device of  claim 25 , wherein the first support connector includes a communications signal connection.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/994,414, filed on Mar. 25, 2020, the content of which is hereby incorporated by reference in its entirety for all purposes. 
    
    
     FIELD 
     The present disclosure relates generally to the field of head-mounted devices. 
     BACKGROUND 
     Head-mounted devices that display computer-generated reality content may include a housing and a structure that allows the housing to be held in place near the eyes of the user. One example of such a structure is a headband. 
     SUMMARY 
     One aspect of the disclosure is a head-mounted device that includes a device housing, a display device that is connected to the device housing to display content to a user as emitted light, an optical system that is configured to direct the emitted light to a user&#39;s eyes, and a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head. The head-mounted device also includes a first headband connector that includes a headband-side connector portion that is connected to the headband at a first end of the headband and a device-side connector portion that is connected to the device housing. The first headband connector is movable between a disconnected position, in which the headband-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion. The first headband connector also includes paired magnetic components that are configured to attract the headband-side connector portion and the device-side connector portion to one another to urge the first headband connector to move to the connected position. 
     In some implementations, the paired magnetic components include a permanent magnet and a ferromagnetic structure. In some implementations, the paired magnetic components include a first permanent magnet that is located on the headband-side connector portion and a second permanent magnet that is located on the device-side connector portion. 
     In some implementations, the first headband connector includes an electrical power connection. In some implementations, the first headband connector includes a communications signal connection. 
     In some implementations, the head-mounted device also includes a second headband connector that includes a headband-side connector portion that is connected to the headband at a second end of the headband and a device-side connector portion that is connected to the device housing. In some implementations, the head-mounted device also a second headband connector that is directly connected to the device housing and is non-releasable with respect to the device housing. 
     In some implementations, the head-mounted device also includes an additional headband connector that is located along the headband and is movable between a connected position and a disconnected position. 
     In some implementations of the head-mounted device, the paired magnetic components include an electromagnet that is operable to generate a magnetic attraction force and application of the magnetic attraction force ceases in response to determining that a current draw by the electromagnet is greater than a threshold value. 
     Another aspect of the disclosure is a head-mounted device that includes a device housing, a display device that is connected to the device housing to display content to a user as emitted light, an optical system that is configured to direct the emitted light to a user&#39;s eyes, and a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head. The head-mounted device also includes a first headband connector that includes a headband-side connector portion that is connected to the headband at a first end of the headband and a device-side connector portion that is connected to the device housing. The first headband connector includes an electromagnet. The first headband connector is movable between a disconnected position, in which the headband-side connector portion is disconnected from the device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion. The head-mounted device also includes a release button that is operable to change operation of the electromagnet to cause the first headband connector to move from the connected position to the disconnected position. 
     In some implementations, the release button is located on the headband at a location that is spaced from the first headband connector. 
     In some implementations, the head-mounted device also includes a power source that is located on the headband and is operable to supply electrical power to the electromagnet. 
     In some implementations, the electromagnet is operable to apply a magnetic attraction force to maintain the first headband connector in the connected position. 
     In some implementations, the release button, when operated by the user, causes the electromagnet to cease application of the magnetic attraction force to cause the first headband connector to move from the connected position to the disconnected position. 
     In some implementations, the first headband connector includes paired magnetic components that are configured to maintain the first headband connector in the connected position when the electromagnet is not operated and the electromagnet is operable to apply a magnetic repulsion force to move the first headband connector from the connected position to the disconnected position when the electromagnet is operated. 
     In some implementations, the release button, when operated by the user, causes the electromagnet to apply the magnetic repulsion force to cause the first headband connector to move from the connected position to the disconnected position. 
     Another aspect of the disclosure is a head-mounted device that includes a device housing, a display device that is connected to the device housing to display content to a user as emitted light, an optical system that is configured to direct the emitted light to a user&#39;s eyes, and a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head. The head-mounted device also includes a headband adjustment device that is connected to the headband and includes adjuster portions, wherein the headband adjustment device is able to contract and expand a length of the headband by moving the adjuster portions with respect to one another. 
     In some implementations, the adjuster portions are connected to one another by connecting structures that allow adjacent ones of the adjuster portions to move toward each other and away from each other. 
     In some implementations, the headband adjustment device includes biasing structures that urge adjacent ones of the adjuster portions to move at least one of toward each other or away from each other. 
     In some implementations, a first pair of adjuster portions are related to one another by an electromagnetic device that is controllable to cause the first pair of adjuster portions to move at least one of toward each other or away from each other. 
     In some implementations, the head-mounted device include a sensor that outputs a signal that represents a magnitude of motion, wherein a magnitude of tension applied to the headband by the headband adjustment device is controlled according to the signal. 
     Another aspect of the disclosure is a head-mounted device that includes a device housing, a display device that is connected to the device housing to display content to a user as emitted light, an optical system that is configured to direct the emitted light to a user&#39;s eyes, a headband that has a first end and a second end and is configured to support the device housing with respect to the user&#39;s head, an accessory component, and an accessory adjustment device. The accessory adjustment device is connected to the headband, supports the accessory component with respect to the headband, and includes a first end portion that is connected to the headband, a second end portion that is connected to the headband, an adjuster portion, and an electromagnetic device, wherein the electromagnetic device is operable to move the adjuster portion between the first end portion and the second end portion to change a location of the accessory component with respect to the headband. 
     In some implementations, the adjuster portion is connected to the first end portion and the second end portion by connecting structures that allow the adjuster portion to move between the first end portion and the second end portion. 
     In some implementations, the accessory component is a loudspeaker. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a block diagram that shows an example of a hardware configuration for a head-mounted device. 
         FIG.  2    is a top view illustration that shows the head-mounted device with a headband in a disconnected position with respect to a device housing. 
         FIG.  3    is a top view illustration that shows the head-mounted device with the headband in a connected position with respect to the device housing. 
         FIG.  4    is a cross-section illustration that shows a first headband connector in the disconnected position. 
         FIG.  5    is a cross-section illustration that shows the first headband connector in the connected position. 
         FIG.  6    is an illustration that shows a headband-side structural connector and a housing-side structural connector according to an example. 
         FIG.  7    is an illustration that shows a headband-side structural connector and a housing-side structural connector according to an example. 
         FIG.  8    is an illustration that shows a headband-side structural connector and a housing-side structural connector according to an example. 
         FIG.  9    is an illustration that shows a headband-side structural connector and a housing-side structural connector according to an example. 
         FIG.  10    is a block diagram that shows an example of a hardware configuration for a head-mounted device. 
         FIG.  11    is a top view illustration that shows the head-mounted device with a headband adjustment device in an expanded position. 
         FIG.  12    is a top view illustration that shows the head-mounted device with the headband adjustment device in a contracted position. 
         FIG.  13    is a side view detail that shows the headband and the headband adjustment device in the expanded position. 
         FIG.  14    is a side view detail that shows the headband and the headband adjustment device in the contracted position. 
         FIG.  15    is a block diagram that shows an example of a hardware configuration for a head-mounted device. 
         FIG.  16    is a top view illustration that shows the head-mounted device and the accessory adjustment device. 
         FIG.  17    is a side view detail that shows the headband and the accessory adjustment device in a first position. 
         FIG.  18    is a side view detail that shows the headband and the accessory adjustment device in a second position. 
         FIG.  19    is a top view illustration that shows a head-mounted device including a headband with multiple headband connectors in a connected position. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosure herein relates to head-mounted devices that are used to show computer-generated reality (CGR) content to users. 
     In some of the implementations that are described herein, a head-mounted device includes a headband connector is movable between a connected positioned and a disconnected position to detach either one end of the headband or both ends of the headband from a device housing of the head-mounted device. This arrangement makes it easier and more convenient for the user to put the device on their head and to remove it. Specific implementations that are described herein also improve packaging in the connector area. Specific implementations also include connectors that use magnets and/or electromagnets to make use easier and more convenient. 
     Some of the implementations that are described herein include a headband adjustment structure that is able to adjust tightness of the headband using electromagnetic adjustment devices. Some of the implementations that are described herein include a headband adjustment structure that is able to adjust the position of an accessory component relative to the headband using electromagnetic adjustment devices. As examples, the accessory component may be a loudspeaker or a health-monitoring device. 
       FIG.  1    is a block diagram that shows an example of a hardware configuration for a head-mounted device  100 . The head-mounted device  100  is intended to be worn on the head of a user and includes components that are configured to display content to the user. Components that are included in the head-mounted device  100  may be configured to track motion of parts of the user&#39;s body, such as the user&#39;s head and hands. Motion tracking information that is obtained by components of the head-mounted device can be utilized as inputs that control aspects of the generation and display of the content to the user, so that the content displayed to the user can be part of a CGR experience in which the user is able to view and interact with virtual environments and virtual objects. As will be explained further herein, CGR experiences include display of computer-generated content independent of the surrounding physical environment (e.g., virtual reality), and display of computer generated content that is overlaid relative to the surrounding physical environment (e.g., augmented reality). 
     In the illustrated example, the head-mounted device  100  includes a device housing  102 , a facial interface  104 , a headband  106 , a processor  108 , a memory  110 , a storage device  112 , a communications device  114 , sensors  116 , a power source  118 , a display device  120 , an optical system  122 , a first headband connector  124 , and a second headband connector  125 . 
     In some implementations of the head-mounted device  100 , some or all of these components may be included in a separate device that is removable. For example, any or all of the processor  108 , the memory  110 , and/or the storage device  112 , the communications device  114 , the sensors  116 , the power source  118 , and the display device  120  may be incorporated in a device such as a smart phone that is connected (e.g., by docking) to the other portions of the head-mounted device  100 . 
     In some implementations of the head-mounted device  100 , the processor  108 , the memory  110 , and/or the storage device  112  are omitted, and the corresponding functions are performed by an external device that communicates with the head-mounted device  100 . In such an implementation, the head-mounted device  100  may include components that support a data transfer connection with the external device using a wired connection or a wireless connection that is established using the communications device  114 . 
     The device housing  102  is a structure that supports various other components that are included in the head-mounted device. The device housing  102  may have a size and shape that corresponds generally to the width of an average person&#39;s head. The device housing  102  may have a height that corresponds generally to the distance between an average person&#39;s forehead and cheek bones such that it extends above and below the average person&#39;s orbital cavities. In one implementation, the device housing  102  may be a frame that other components of the head-mounted device are connected to. In some implementations, the device housing  102  may be an enclosed structure such that certain components of the head-mounted device  100  are contained within the device housing  102  and thereby protected from damage. In some implementations, the device housing  102  may be an eyeglasses style frame. 
     The facial interface  104  is connected to the device housing  102  and is located at areas around a periphery of the device housing  102  where contact with the user&#39;s face is likely. The facial interface  104  functions to conform to portions of the user&#39;s face to allow the headband  106  to be tensioned to an extent that will restrain motion of the device housing  102  with respect to the user&#39;s head. The facial interface  104  may also function to reduce the amount of light from the physical environment around the user that reaches the user&#39;s eyes. The facial interface  104  may contact areas of the user&#39;s face, such as the user&#39;s forehead, temples, and cheeks. The facial interface  104  may be formed from a compressible material, such as open-cell foam or closed cell foam. In some implementations, the facial interface  104  is omitted from the head-mounted device  100 , such as when the head-mounted device  100  is implemented using an eyeglasses-type configuration. 
     The headband  106  is connected to the device housing  102 . The headband  106  is a component or collection of components that function to secure the device housing  102  in place with respect to the user&#39;s head so that the device housing  102  is restrained from moving with respect to the user&#39;s head and maintains a comfortable position during use. The headband  106  can be implemented using rigid structures, elastic flexible straps, or inelastic flexible straps. 
     The processor  108  is a device that is operable to execute computer program instructions and is operable to perform operations that are described by the computer program instructions. The processor  108  may be implemented using one or more conventional devices and/or more or more special-purpose devices. As examples, the processor  108  may be implemented using one or more central processing units, one or more graphics processing units, one or more application specific integrated circuits, and/or one or more field programmable gate arrays. The processor  108  may be provided with computer-executable instructions that cause the processor  108  to perform specific functions. The memory  110  may be one or more volatile, high-speed, short-term information storage devices such as random-access memory modules. 
     The storage device  112  is intended to allow for long term storage of computer program instructions and other data. Examples of suitable devices for use as the storage device  112  include non-volatile information storage devices of various types, such as a flash memory module, a hard drive, or a solid-state drive. 
     The communications device  114  supports wired or wireless communications with other devices. Any suitable wired or wireless communications protocol may be used. 
     The sensors  116  are components that are incorporated in the head-mounted device  100  to generate sensor output signals to are used as inputs by the processor  108  for use in generating CGR content and controlling tension, as will be described herein. The sensors  116  include components that facilitate motion tracking (e.g., head tracking and optionally handheld controller tracking in six degrees of freedom). The sensors  116  may also include additional sensors that are used by the device to generate and/or enhance the user&#39;s experience in any way. The sensors  116  may include conventional components such as cameras, infrared cameras, infrared emitters, depth cameras, structured-light sensing devices, accelerometers, gyroscopes, and magnetometers. The sensors  116  may also include biometric sensors that are operable to physical or physiological features of a person, for example, for use in user identification and authorization. Biometric sensors may include fingerprint scanners, retinal scanners, and face scanners (e.g., two-dimensional and three-dimensional scanning components operable to obtain image and/or three-dimensional surface representations). Other types of devices can be incorporated in the sensors  116 . The information that is generated by the sensors  116  is provided to other components of the head-mounted device  100 , such as the processor  108 , as inputs. 
     The power source  118  supplies electrical power to components of the head-mounted device  100 . The power source  118  may supported by the device housing  102 , may be supported by the headband  106 , or may be electrically connected to electrical components of the head-mounted device  100  without a supporting physical connected to structural components of the head-mounted device  100 . In some implementations, the power source  118  is a wired connection to electrical power. In some implementations, the power source  118  may include a battery of any suitable type, such as a rechargeable battery. In implementations that include a battery, the head-mounted device  100  may include components that facilitate wired or wireless recharging. 
     The display device  120  is connected to the device housing  102  and functions to display content to the user in the form of emitted light that is output by the display device  120  and is directed toward the user&#39;s eyes by the optical system  122 . The display device  120  is a light-emitting display device, such as a video display of any suitable type, that is able to output images in response to a signal that is received from the processor  108 . The display device  120  may be of the type that selectively illuminates individual display elements according to a color and intensity in accordance with pixel values from an image. As examples, the display device may be implemented using a liquid-crystal display (LCD) device, a light-emitting diode (LED) display device, a liquid crystal on silicon (LCoS) display device, an organic light-emitting diode (OLED) display device, or any other suitable type of display device. The display device  120  may include multiple individual display devices (e.g., two display screens or other display devices arranged side-by-side in correspondence to the user&#39;s left eye and the user&#39;s right eye). 
     The optical system  122  is associated with the display device  120  and is optically coupled to the display device  120 . The optical system is connected to the device housing  102  such that portions of the optical system  122  (e.g., lenses) are positioned adjacent to the user&#39;s eyes. The optical system  122  directs the emitted light from the display device  120  to the user&#39;s eyes. In some implementations, the optical system  122  may be configured isolate the emitted light from environment light (e.g., as in a virtual reality type system), so that a scene perceived by the user is defined only by the emitted light and not by the environment light. In some implementations, the optical system  122  may be configured to combine the emitted light with environmental light so that the scene perceived by the user is defined by the emitted light and the environment light. In some implementations, the optical system  122  may combine the emitted light and the environment light so that a spatial correspondence is established between the emitted light and the environmental light to define the scene that is perceived by the user (e.g., as in an augmented reality type system). The optical system  122  may include lenses, reflectors, polarizers, filters, optical combiners, and/or other optical components. 
     The first headband connector  124  and the second headband connector  125  are releasable connecting devices that connect the headband  106  to the device housing  102  and allow the headband  106  to be partly or fully disconnected from the device housing  102 . Partial disconnection means that a first end of the headband  106  is disconnected from the device housing  102  while a second end remains connected. Full disconnection means both first and second ends of the headband  106  are releasably connected to the device housing  102  and the first headband connector  124  includes releasable connections at both ends that allow the headband  106  to be completely detached from the device housing  102  and subsequently reattached. 
       FIG.  2    is a top view illustration that shows the head-mounted device  100  with the headband  106  in a disconnected position with respect to the device housing  102 .  FIG.  3    is a top view illustration that shows the head-mounted device  100  with the headband  106  in a connected position with respect to the device housing  102 . 
     The headband  106  is connected to the device housing  102  by a first headband connector  124  and a second headband connector  125 , which are implementations of the first headband connector  124 . The first headband connector  124  connects a first end  232  of the headband  106  to a first lateral side  234  of the device housing  102 . The second headband connector  125  connects a second end  233  of the headband  106  to a second lateral side  235  of the device housing  102 . The first headband connector  124  and the second headband connector  125  allow the headband  106  to be moved between the disconnected position and the connected position. In the disconnected position ( FIG.  2   ), both of the first end  232  of the headband  106  and the second end  233  of the headband  106  are disconnected from the device housing  102 , such that the headband  106  is separable from the device housing  102 . In the connected position ( FIG.  3   ), both of the first end  232  of the headband  106  and the second end  233  of the headband  106  are connected to the device housing  102 . 
     In the illustrated implementation, the first headband connector  124  and the second headband connector  125  define releasable connections at each of the first end  232  and the second end  233  of the headband  106 . In an alternative implementation, the first headband connector  124  defines a releasable connection at the first end  232  of the headband  106 , but the second headband connector  125  is omitted. Instead, the second end  233  of the headband  106  is directly connected to the device housing  102  by a non-releasable connection (i.e., the second end  233  of the headband  106  is releasable with respect to the device housing  102 . The non-releasable connection of the second end  233  of headband  106  to the device housing  102  may be implemented using any structure that does not allow the second end  233  of the headband  106  to be readily detached from the device housing  102 . As examples, the non-releasable connection may be a fastener, a bracket, a pivot joint, or other structure. 
       FIG.  4    is a cross-section illustration that shows the first headband connector  124  in the disconnected position.  FIG.  5    is a cross-section illustration that shows the first headband connector  124  in the connected position. The second headband connector  125  may be configured in the same manner as the first headband connector  124 , and the description of the first headband connector is applicable to the second headband connector  125 . 
     The first headband connector  124  includes a headband-side connector portion  436  and a housing-side connector portion  438 . The headband-side connector portion  436  includes components that can be attached to and released from components that are included in the housing-side connector portion  438  in order to define detachable electrical and structural (e.g., supporting) connections between the headband  106  and the device housing  102 . The headband-side connector portion  436  and the housing-side connector portion  438  cooperate to define the connected position and the disconnected position for the headband  106  by defining corresponding connected and disconnected positions for the first headband connector  124 . In the illustrated example, the first headband connector  124  is in the connected position when the headband-side connector portion  436  is connected to the housing-side connector portion  438 , and with the first headband connector  124  is in the disconnected position when the headband-side connector portion  436  is disconnected from the housing-side connector portion  438 . 
     In the illustrated example, the headband-side connector portion  436  includes a headband-side power connector  440 , and the housing-side connector portion  438  includes a housing-side power connector  441 . The headband-side power connector  440  and the housing-side power connector  441  define an electrical power connection for the first headband connector  124 . The headband-side power connector  440  and the housing-side power connector  441  are connected when headband-side connector portion  436  is connected to the housing-side connector portion  438 . The headband-side power connector  440  and the housing-side power connector  441  are disconnected when headband-side connector portion  436  is disconnected from the housing-side connector portion  438 . 
     The headband  106  may include a headband-side power cable  446  that is connected to the headband-side power connector  440  and is connected to power-consuming or power supplying components that are connected to the headband  106 . The device housing  102  may include a housing-side power cable  447  that is connected to the housing-side power connector  441  and is connected to power-consuming or power supplying components that are connected to the device housing  102 . 
     When connected, the headband-side power connector  440  and the housing-side power connector  441  allow an electrical power supply connection to be established between the headband  106  and the device housing  102 . This allows, for example, supply of electrical power to components that are located in the device housing  102  from a battery that is connected to the headband  106 , or supply or electrical power to components that are connected to the headband  106  from a battery that is located in the device housing  102 . 
     In the illustrated example, the headband-side connector portion  436  includes a headband-side signal connector  442 , and the housing-side connector portion  438  includes a housing-side signal connector  443 . The headband-side signal connector  442  and the housing-side signal connector  443  define a communications signal connection for the first headband connector  124 . The headband-side signal connector  442  and the housing-side signal connector  443  are connected when the headband-side connector portion  436  is connected to the housing-side connector portion  438 . The headband-side signal connector  442  and the housing-side signal connector  443  are disconnected when the headband-side connector portion  436  is disconnected from the housing-side connector portion  438 . 
     The headband  106  may include a headband-side signal cable  448  that is connected to the headband-side signal connector  442  and is connected to electrical components that are connected to the headband  106  and which send and/or receive signals and/or data, such as sensor output signals or command values. The device housing  102  may include a housing-side signal cable  449  that is connected to the housing-side signal connector  443  and is connected to electrical components that are connected to the device housing  102  and which send and or receive signals and or data such as sensor output signals or command values. 
     When connected, the headband-side signal connector  442  and the housing-side signal connector  443  allow a signal transmission connection to be established between the headband  106  and the device housing  102 . This allows, for example, sensor output signals from sensors that are located on the headband  106  to be transmitted to components that are located in the device housing  102 , or for command values from components that are located in the device housing  102  to be transmitted to components that are located on the headband  106 . An example, the signal transmission connection can allow an audio signal to be transmitted from components that are located in the device housing  102  to a loudspeaker that is located on the headband  106 . 
     In the illustrated example, the headband-side connector portion  436  includes a headband-side structural connector  444  according to a first example, and the housing-side connector portion  438  includes a housing-side structural connector  445  according to a first example. The headband-side structural connector  444  and the housing-side structural connector  445  define a releasable structural connection between the headband-side connector portion  436  and the housing-side connector portion  438  of the first headband connector  124 . The releasable structural connection, when connected, is configured to resist separation of the headband-side connector portion  436  from the housing-side connector portion  438 . The releasable structural connection also allows for load transfer between the headband  106  and the device housing  102  in order to support the head-mounted device  100  in a fixed position with respect to the head of the user. The releasable structural connection is also configured to support torque loads and shear loads across the first headband connector  124  by resisting relative motion of the headband-side connector portion  436  and the housing-side connector portion  438  of the first headband connector  124 . 
     As examples, the headband-side structural connector  444  and the housing-side structural connector  445  may be implemented using magnetic components, electromagnets, and/or mechanical connecting devices. Magnetic components include permanent magnets and ferromagnetic structures. Magnetic components are arranged in pairs that generate at least one of an attractive force or a repulsive force between them. A pair of magnetic components includes at least one permanent magnet, which is paired with a ferromagnetic structure or another permanent magnet. Electromagnets are arranged in a pair with a permanent magnet, a ferromagnetic structure, or another electromagnet. 
     Multiple types of components may be included in each of the headband-side structural connector  444  and the housing-side structural connector  445 . In a first implementation, the headband-side structural connector  444  is a magnet and the housing-side structural connector  445  is a ferromagnetic structure. A ferromagnetic structure is defined herein as a structure that reacts to a magnet, such as a permanent magnet or a structure formed from iron or another material that is attracted to magnets. In a second implementation, the headband-side structural connector  444  is a first magnet and the housing-side structural connector  445  is a second magnet. In third implementation, the headband-side structural connector  444  is an electromagnet and the housing-side structural connector  445  is a ferromagnetic structure. 
     Thus, in one implementation of the first headband connector  124 , the first headband connector  124  is movable between a disconnected position, in which a headband-side connector portion is disconnected from a device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion. In this implementation, the first headband connector  124  includes magnetic components that are configured to attract the headband-side connector portion and the device-side connector portion to one another to urge the first headband connector  124  to move to the connected position. 
       FIG.  6    is an illustration that shows a headband-side structural connector  644  and a housing-side structural connector  645  according to an example. The headband-side structural connector  644  and the housing-side structural connector  645  may be incorporated in the first headband connector  124  or the second headband connector  125  in place of the headband-side structural connector  444  and the housing-side structural connector  445 . 
     The headband-side structural connector  644  and the housing-side structural connector  645  facilitate movement between connected and disconnected positions. The headband-side structural connector  644  includes an array of magnetic components that is defined by magnetic components  646   a ,  646   b , and  646   c . The housing-side structural connector  645  includes an array of magnetic components that is defined by magnetic components  647   a ,  647   b , and  647   c.    
     Pairs of magnetic components from the headband-side structural connector  644  and the housing-side structural connector  645  are attracted to one another. Magnetic attraction of the pairs of magnetic components urges the headband-side structural connector  644  and the housing-side structural connector  645  toward the connected position and also resists disconnection of the headband-side structural connector  644  and the housing-side structural connector  645  by movement from the connected position to the disconnected position. 
     As an example, the pairs of magnetic components may include a first pair of magnetic components  646   a ,  647   a , a second pair of magnetic components  646   b ,  647   b , and a third pair of magnetic components  646   c ,  647   c . As one example, each pair of magnetic components may include a permanent magnet and a ferromagnetic structure (e.g., iron or a permanent magnet) that are arranged so that the permanent magnet is attracted to the ferromagnetic structure. As another example, each pair of magnetic components may include a first magnet and a second magnet that are oriented with opposite poles facing one another (e.g., a south pole facing a north pole) such that the magnets from the pair are attracted to one another. 
     To move from the disconnected position to the connected position, the user places the headband-side structural connector  644  near the housing-side structural connector  645  such that magnetic attraction between the pairs of magnetic components causes connection of the headband-side structural connector  644  and the housing-side structural connector  645 . To move from the connected position to the disconnected position, the user applies sufficient force to the headband to overcome the magnetic attraction force between the pairs of magnetic components of the headband-side structural connector  644  and the housing-side structural connector  645 . 
     Thus, in one implementation of the first headband connector  124 , the first headband connector  124  is movable between a disconnected position, in which a headband-side connector portion is disconnected from a device-side connector portion, and a connected position, in which the headband-side connector portion is connected to the device-side connector portion. In this implementation, the first headband connector  124  includes paired magnetic components, such as the first pair of magnetic components  646   a ,  647   a , the second pair of magnetic components  646   b ,  647   b , and the third pair of magnetic components  646   c ,  647   c , that are arranged on the headband-side connector portion and the device-side connector portion. The paired magnetic components are configured to attract the headband-side connector portion and the device-side connector portion to one another to urge the first headband connector  124  to move to the connected position. 
       FIG.  7    is an illustration that shows a headband-side structural connector  744  and a housing-side structural connector  745  according to an example. The headband-side structural connector  744  and the housing-side structural connector  745  may be incorporated in the first headband connector  124  or the second headband connector  125  in place of the headband-side structural connector  444  and the housing-side structural connector  445 . 
     The headband-side structural connector  744  and the housing-side structural connector  745  facilitate movement between connected and disconnected positions. The headband-side structural connector  744  includes an electromagnet  748 . The housing-side structural connector  745  includes a magnetic component  747 , such as a ferromagnetic structure. 
     The electromagnet  748  of the headband-side structural connector  744  is operable to apply a magnetic attraction force to the magnetic component  747  of the housing-side structural connector  745  when an electric current is applied to the electromagnet  748  to maintain the headband-side structural connector  744  and a housing-side structural connector  745  in the connected position. To apply electric current to the electromagnet  748 , a power source  750  and a release button  752  are electrically connected to the electromagnet  748 . As an example, the power source  750  may be a battery that is located on the headband of the device. The release button  752  may be a physical switch or a touch sensitive area that is located on the headband at a location that is spaced from the headband connector to reduce the number of components that need to be located in the area of the headband connector. 
     The power source  750  applies an electric current to the electromagnet  748  to attract the magnetic component  747  at to the electromagnet  748 . When the headband-side structural connector  744  is moved near the housing-side structural connector  745 , the magnetic attraction force that is applied to the magnetic component  747  by the electromagnet  748  causes the headband-side structural connector  744  and the housing-side structural connector  745  to move to the connected position. 
     The release button  752  is operable to change operation of the electromagnet to cause the headband connector to move from the connected position to the disconnected position. For example, the release button  752  may be operated by the user to interrupt supply of the electric current to the electromagnet  748  by the power source  750 . Upon operation of the release button  752  by the user, the electromagnet  748  no longer generates a magnetic attraction force that is sufficient to maintain connection of the headband-side structural connector  744  to the housing-side structural connector  745 . As a result, the headband-side structural connector  744  and the housing-side structural connector  745  move to the disconnected position upon operation of the release button  752 . 
     Thus, the electromagnet  748  is operable to apply a magnetic attraction force to maintain a headband connector (e.g., the first headband connector  124  of the second headband connector  125 ) in the connected position, and the release button  752 , when operated by the user, causes the electromagnet  748  to cease application of the magnetic attraction to cause the headband connector to move from the connected position to the disconnected position. As examples, the electromagnet  748  may cease application of the magnetic attraction when electrical power is no longer supplied to the electromagnet  748  from the power source  750 , or the electromagnet  748  may cease application of the magnetic attraction when a polarity of the electrical power that is supplied to the electromagnet  748  from the power source  750  is reversed so that the electromagnet  748  generates a repulsive force instead of an attractive force. 
     In some implementations, operation of the electromagnet  748  may be controlled in part by a sensing arrangement that detects proximity of the headband-side structural connector  744  to the housing-side structural connector  745 . As one example, a mechanical switch may be associated with the headband-side structural connector  744  to detect proximity of the housing-side structural connector  745 . As another example, a non-contact sensor may be associated with the headband-side structural connector  744  to detect proximity of the housing-side structural connector  745 . Examples of non-contact sensors include photosensors and reed switches (e.g., to detect proximity of a magnet associated with the housing-side structural connector  745 ). In these implementations, the electromagnet  748  is only operated (e.g., by supply of electric current to it) when proximity of the housing-side structural connector  745  is detected, but the release button  752  continues to function as previously described, by interrupting supply of electric current to the electromagnet  748  when operated. 
     In some implementations, operation of the electromagnet  748  may be controlled in part by a sensing arrangement that detects a force applied to the headband based on current draw by the electromagnet  748 . Current draw by the electromagnet  748  can be measured to detect a user intention to move from the connected position to the disconnected position because the current draw of the electromagnet  748  will increase in response to an applied force. It can be determined that the user intends to release the headband connector when the current draw of the electromagnet  748  exceeds a threshold value. Thus, the electromagnet  748  may release in response to detecting current draw above a threshold in response to an applied force. As one example, the electromagnet may cease application of the magnetic attraction to release the electromagnet  748  when the current draw exceeds a threshold in response to an applied force. As another example, the electromagnet  748  may reverse a polarity of the electrical power that is supplied to the electromagnet  748  from the power source  750  is reversed so that the electromagnet  748  generates a repulsive force instead of an attractive force when the current draw of the electromagnet  748 . 
     In some implementations, the magnitude of the attraction force applied by the electromagnet  748  is controlled based on one or more factors. As one example, motion of the head mounted device (e.g., the head-mounted device  100 ) is measured using sensors that are located in the device housing or on the headband. The motion of the device that is measured by the sensors may include a velocity value and/or an acceleration value. As an example, the sensors can be accelerometers or other sensors that measure motion of the device. The magnitude of the attraction force can be varied based on motion of the device, for example, by increasing the magnitude of the attraction force applied by the electromagnet  748  when an amount of sensed motion is above a threshold value, and by decreasing the magnitude of the attraction force that is applied by the electromagnet  748  when an amount of sensed motion is below a threshold value. As another example, information that describes a user preference can be used to set the magnitude of the attraction force that is applied by the electromagnet  748 . As another example, the user may be prompted to select the magnitude of the attraction force that is applied by the electromagnet  748 . 
     As another example, information that is associated with an application can be used to set the magnitude of the attraction force applied by the electromagnet  748 . For example, a value that describes the magnitude of attraction force to be applied by the electromagnet  748  can be supplied by the application and used to control the electromagnet  748 . As another example, a category value that corresponds to the magnitude of attraction force to be applied by the electromagnet  748  can be supplied by the application and used to control the electromagnet  748 . As examples, category values can correspond to a high-motion category for which a high attraction force is to be applied by the electromagnet  748  and a low motion category for which a relatively lower attraction force is to be applied by the electromagnet  748 . 
     As another example, the forced applied by the electromagnet  748  may be controlled based on the likelihood that the headband will be snagged, for example, based on the environment where the device is being used. By reducing the holding force applied by the electromagnet  748 , the headband can be released easily if snagged. As another example a tension sensor can detect that force above a threshold value has been applied to the headband, and the electromagnet  748  can be controlled to release the headband. As another example, by measuring tension applied to the band when the electromagnet  748  releases, the device can determine that the electromagnet  748  is dirty, and alert the user. 
       FIG.  8    is an illustration that shows a headband-side structural connector  844  and a housing-side structural connector  845  according to an example. The headband-side structural connector  844  and the housing-side structural connector  845  may be incorporated in the first headband connector  124  or the second headband connector  125  in place of the headband-side structural connector  444  and the housing-side structural connector  445 . 
     The headband-side structural connector  844  and the housing-side structural connector  845  facilitate movement between connected and disconnected positions. The headband-side structural connector  844  includes an electromagnet  848  and a magnetic component  846 . The housing-side structural connector  845  includes a first magnetic component  847   a  and a second magnetic component  847   b.    
     The magnetic component  846  of the headband-side structural connector  844  and the second magnetic component  847   b  of the housing-side structural connector  845  are operable to generate a magnetic attraction force when the headband-side structural connector  844  is in proximity of the housing-side structural connector  845 . The magnetic attraction force between the headband-side structural connector  844  and the housing-side structural connector  845  is operable to move the headband-side structural connector  844  and the housing-side structural connector  845  to the connected position, and retain them in the connected position until released. 
     The electromagnet  848  is connected to a power source  850  and a release button  852 . The electromagnet  848  is operable to generate a magnetic repulsion force that repels the first magnetic component  847   a  when an electric current is applied to the electromagnet  848 . The release button  852  is operable to change operation of the electromagnet  848  to cause the headband connector to move from the connected position to the disconnected position. For example, the electric current may be applied to the electromagnet  848  from the power source  850  in response to operation of the release button  852 , which causes disconnection of the headband-side structural connector  844  from the housing-side structural connector  845  by application of a repulsive force that is generated by the release button  852 . The electromagnet  848  is otherwise similar to the electromagnet  748  and the description of the electromagnet  748  is applicable to the electromagnet  848  except as noted above. 
     For example, a headband connector may include paired magnetic components that are configured to maintain the headband connector in the connected position when the electromagnet  848  is not operated. The electromagnet  848  is operable to apply a magnetic repulsion force to move the headband connector from the connected position to the disconnected position when the electromagnet  848  is operated. Thus, when the release button  852  is operated by the user, this causes the electromagnet  848  to apply the magnetic repulsion force (e.g., by supply of electrical power from the power source  850  to the electromagnet  848  (to cause the headband connector to move from the connected position to the disconnected position. 
       FIG.  9    is an illustration that shows a headband-side structural connector  944  and a housing-side structural connector  945  according to an example. The headband-side structural connector  944  and the housing-side structural connector  945  may be incorporated in the first headband connector  124  or the second headband connector  125  in place of the headband-side structural connector  444  and the housing-side structural connector  445 . 
     The headband-side structural connector  944  and the housing-side structural connector  945  facilitate movement between connected and disconnected positions. The headband-side structural connector  944  includes an electromagnet  948  and a first mechanical connector part  956 . The housing-side structural connector  945  includes a magnetic component  947  and a second mechanical connector part  958 . 
     The first mechanical connector part  956  and the second mechanical connector part  958  are engageable with one another two define a mechanical connection between the headband-side structural connector  944  and the housing-side structural connector  945 . As examples, the first mechanical connector part  956  and the second mechanical connector part  958  may include a latching mechanism, a friction fit mechanism, or another type of mechanical connection mechanism. The first mechanical connector part  956  and the second mechanical connector part  958  define the connected position upon engagement with one another. The first mechanical connector part  956  and the second mechanical connector part  958  are configured to release from one another in response to an applied force that moves the first mechanical connector part  956  away from the second mechanical connector part  958 . Thus, disconnection may occur in response to application of a separating force in excess of a threshold value that exceeds a holding force between the first mechanical connector part  956  and the second mechanical connector part  958 . 
     The electromagnet  948  is connected to a power source  950  and a release button  952 . The electromagnet  948  is operable to generate a magnetic repulsion force that repels the magnetic component  947  when an electric current is applied to the electromagnet  948 . The electric current is applied to the electromagnet  948  from the power source  950  in response to operation of the release button  952 , which causes disconnection of the headband-side structural connector  944  from the housing-side structural connector  945 . The electromagnet  948  is otherwise similar to the electromagnet  748  and the description of the electromagnet  748  is applicable to the electromagnet  948  except as noted above. 
       FIG.  10    is a block diagram that shows an example of a hardware configuration for a head-mounted device  1000 . The head-mounted device  1000  is intended to be worn on the head of a user and includes components that are configured to display content to the user. Components that are included in the head-mounted device  1000  may be configured to track motion of parts of the user&#39;s body, such as the user&#39;s head and hands. Motion tracking information that is obtained by components of the head-mounted device can be utilized as inputs that control aspects of the generation and display of the content to the user, so that the content displayed to the user can be part of a CGR experience in which the user is able to view and interact with virtual environments and virtual objects. As will be explained further herein, CGR experiences include display of computer-generated content independent of the surrounding physical environment (e.g., virtual reality), and display of computer generated content that is overlaid relative to the surrounding physical environment (e.g., augmented reality). 
     The head-mounted device  1000  includes components that are similar to those found in the head-mounted device  100 , Except as otherwise described herein. In the illustrated example, the head-mounted device  1000  includes a device housing  1002 , a facial interface  1004 , a headband  1006 , a processor  1008 , a memory  1010 , a storage device  1012 , a communications device  1014 , sensors  1016 , a power source  1018 , a display device  1020 , an optical system  1022 , which may be implemented in accordance with the description of like-named components from the head-mounted device  100 , and the description of those components is hereby incorporated by reference in the description of the head-mounted device  1000 . The head-mounted device  1000  also includes a headband adjustment device  1026 . 
     In some implementations of the head-mounted device  1000 , some or all of these components may be included in a separate device that is removable. For example, any or all of the processor  1008 , the memory  1010 , and/or the storage device  1012 , the communications device  1014 , the sensors  1016 , the power source  1018 , and the display device  1020  may be incorporated in a device such as a smart phone that is connected (e.g., by docking) to the other portions of the head-mounted device  1000 . 
     In some implementations of the head-mounted device  1000 , the processor  1008 , the memory  1010 , and/or the storage device  1012  are omitted, and the corresponding functions are performed by an external device that communicates with the head-mounted device  1000 . In such an implementation, the head-mounted device  1000  may include components that support a data transfer connection with the external device using a wired connection or a wireless connection that is established using the communications device  1014 . 
       FIG.  11    is a top view illustration that shows the head-mounted device  1000  with the headband adjustment device  1026  in an expanded position.  FIG.  12    is a top view illustration that shows the head-mounted device  1000  with the headband adjustment device  1026  in a contracted position. In the illustrated example, two of the headband adjustment devices are connected to the headband  1006 . The number of the headband adjustment devices may be varied. 
     The headband adjustment device  1026  is located on the headband  1006  and is operable to expand and contract a length of the headband  1006 . By changing the length of the headband  1006 , the fit of the headband  1006  relative to the user&#39;s head may be adjusted, and the amount of force applied to the user&#39;s head by the headband  1006  may be adjusted. The headband  1006  may be formed from a flexible and elastic material. This allows the headband  1006  to be expanded and contracted by expansion and contraction of the headband adjustment device  1026 . 
     The headband adjustment device  1026  may be configured to expand and contract in response to commands (e.g., using buttons, a user interface, verbal commands, etc.) from the user. Commands from the user may be received and processed by components of the head-mounted device  1000 , such as the processor  1008 , and relayed to the headband adjustment device  1026  in the form of control signals, such as a variable voltage that controls whether the headband adjustment device expands, contracts, or remains in its current position. 
     The headband adjustment device  1026  may be configured to expand and retract in response to signals from the sensors  1016 . As one example, the headband adjustment device  1026  may be configured to expand or contract the length of the headband  1006  in response to signals from a tension sensor that detects an amount of tension placed on the headband  1006 . As another example, the headband adjustment device  1026  may be configured to expand or contract the length of the headband  1006  in response to signals from a motion sensor that detects a magnitude of movement (e.g., velocity and/or acceleration) experienced by the head-mounted device  1000 . As another example, the headband adjustment device  1026  may be configured to expand or contract the length of the headband  1006  in response to determining a magnitude of movement (e.g., velocity and/or acceleration) experienced by the head-mounted device  1000  based on images (e.g., video frames) obtained by cameras that are included in the head-mounted device  1000 . Thus, signals from the sensors  1016  (and/or other components such as the optical system  1022 ) may be used as feedback signals to continuously control adjustment of the headband  1006  using the headband adjustment device  1026 . 
     For example, the head-mounted device  1000  may control the headband adjustment device  1026  to automatically tighten in response to a high amount of detected motion or increase of detected motion of the head-mounted device  1000  (e.g., a magnitude of motion above a threshold) and automatically loosen in response to a low amount of detected motion or a decrease in detected motion of the head-mounted device  1000 . Thus, for example, the head-mounted device  1000  may include a sensor (e.g., sensors  1016 ) that outputs a signal that represents a magnitude of motion, wherein a magnitude of tension applied to the headband  1006  by the headband adjustment device  1026  is controlled according to the signal. 
       FIG.  13    is a side view detail that shows the headband  1006  and the headband adjustment device  1026  in the expanded position.  FIG.  14    is a side view detail that shows the headband  1006  and the headband adjustment device  1026  in the contracted position. The headband adjustment device  1026  includes adjuster portions  1360  (e.g., two or more of the adjuster portions). In the illustrated example, the headband adjustment device  1026  includes nine of the adjuster portions  1360 , but the number of the adjuster portions  1360  may be varied. The adjuster portions  1360  are rigid or semi rigid structures that are able to move toward each other to contract the length of the headband  1006  and away from each other to expand the length of the headband  1006 . Thus, the headband adjustment device  1026  is connected to the headband  1006  and is able to contract and expand a length of the headband  1006  by moving the adjuster portions  1360  with respect to one another. 
     In the illustrated example, the adjuster portions  1360  are upright, narrow structures that each extend in a generally upward/downward direction relative to the headband  1006 , and are spaced from each other along a length direction of the headband  1006  in the expanded position. At least two of the adjuster portions  1360  are directly connected to the headband  1006  and are movable with respect to each other to expand and contract the length of the headband  1006 . In some implementations, all of the adjuster portions  1360  are directly connected to the headband  1006  and are movable with respect to each other to expand and contract the length of the headband  1006 . 
     The adjuster portions  1360  may be connected to one another by connecting structures  1362  that allow the adjuster portions  1360  to move toward each other and away from each other. As an example, the connecting structures  1362  may be structures such as rods or cables that the adjuster portions are connected to by fixed connections and/or sliding connections. Biasing structures  1364  such as springs may be placed between adjacent pairs of the adjuster portions  1360  to urge the adjacent pairs of the adjuster portions  1360  away from each other (e.g., using compression springs) or to urge the adjacent pairs of adjuster portions  1360  toward each other (e.g., using tension springs). 
     Adjacent ones of the adjuster portions  1360  are related to each other by an electromagnetic device that includes an electromagnet  1366   a  and a magnetic component  1366   b . The magnetic component  1366   b  may be a ferromagnetic structure that may be attracted to and/or repelled by the electromagnet  1366   a.    
     In some implementations, the electromagnetic devices are configured such that a repulsive force generated by one of the electromagnets  1366   a  relative to a respective one of the magnetic components  1366   b  is used to move adjacent pairs of the adjuster portions  1360  away from each other to expand the headband  1006  (e.g., against a spring force applied by tension springs included in the biasing structures  1364 ) as shown in  FIG.  13   . 
     In some implementations, the electromagnetic devices are configured such that an attractive force generated by one of the electromagnets  1366   a  relative to a respective one of the magnetic components  1366   b  is used to move adjacent pairs of the adjuster portions  1360  toward each other to contract the headband  1006  (e.g., against a spring force applied by compression springs included in the biasing structures  1364 ) as shown in  FIG.  14   . 
     In some implementations, adjacent ones of the adjuster portions  1360  may be held against one another (e.g., in engagement with one another) using pairs of permanent magnets and ferromagnetic structures that attract adjacent pairs of the adjuster portions  1360  to each other until repelled by a repulsive force generated by one of the electromagnets  1366   a  relative to a respective one of the magnetic components  1366   b.    
     By movement of the adjuster portions  1360  toward each other, the length of the headband  1006  is decreased. By movement of the adjuster portions  1360  away from each other, the length of the headband  1006  is increased. In implementations where the headband  1006  is formed from a flexible elastic material, increasing the length of the headband  1006  can include stretching the elastic material to make it longer, and decreasing the length of the headband  1006  can include relaxing a degree to which the elastic material is stretched to make it shorter. The headband  1006  may also decrease in length by folding and increase in length by unfolding. in some implementations, the headband  1006  is discontinuous, and is connected to a first end of the headband adjustment device  1026  and to a second end of the headband adjustment device  1026 . In such an implementation, the headband adjustment device  1026  defines part of the length of the headband  1006 , and increases and decreases in length of the headband adjustment device  1026  by relative movement of the adjuster portions  1360  cause the length of the headband  1006  to increase and decrease in length. 
     In the illustrated example, the headband adjustment device  1026  is shown in a fully expanded position and in a fully contracted position. It should be understood, that the degree by which the headband  1006  is lengthened or shortened can be controlled by controlling movement of adjacent pairs of the adjuster portions  1360  independently of each other. Thus, by moving one pair of the adjuster portions  1360  together, the headband  1006  is shortened by a first amount, and by moving two pairs of the adjuster portions together, the headband  1006  is shortened by a second amount that is larger than the first amount. This allows for shortening and lengthening of the headband  1006  between a minimum length and a maximum length. 
       FIG.  15    is a block diagram that shows an example of a hardware configuration for a head-mounted device  1500 . The head-mounted device  1500  is intended to be worn on the head of a user and includes components that are configured to display content to the user. Components that are included in the head-mounted device  1500  may be configured to track motion of parts of the user&#39;s body, such as the user&#39;s head and hands. Motion tracking information that is obtained by components of the head-mounted device can be utilized as inputs that control aspects of the generation and display of the content to the user, so that the content displayed to the user can be part of a CGR experience in which the user is able to view and interact with virtual environments and virtual objects. As will be explained further herein, CGR experiences include display of computer-generated content independent of the surrounding physical environment (e.g., virtual reality), and display of computer generated content that is overlaid relative to the surrounding physical environment (e.g., augmented reality). 
     The head-mounted device  1500  includes components that are similar to those found in the head-mounted device  100 , Except as otherwise described herein. In the illustrated example, the head-mounted device  1500  includes a device housing  1502 , a facial interface  1504 , a headband  1506 , a processor  1508 , a memory  1510 , a storage device  1512 , a communications device  1514 , sensors  1516 , a power source  1518 , a display device  1520 , an optical system  1522 , which may be implemented in accordance with the description of like-named components from the head-mounted device  100 , and the description of those components is hereby incorporated by reference in the description of the head-mounted device  1500 . 
     The head-mounted device  1500  also includes an accessory adjustment device  1528  and an accessory component  1529 .  FIG.  16    is a top view illustration that shows the head-mounted device  1500  and the accessory adjustment device  1528 . The accessory adjustment device  1528  is connected to the headband  1506  and functions to adjust the position of the accessory component  1529  relative to the headband  1506 , for example, by moving the accessory component forward and rearward along the length direction of the headband  1506 . As one example, the accessory component  1529  may be a loudspeaker, and the accessory adjustment device  1528  may connect the loudspeaker to the headband  1506  and allow adjustment of the position of the loudspeaker relative to the headband  1506 . This would allow the accessory adjustment device  1528  to, for example, align the loudspeaker or other accessory component  1529  relative to the user&#39;s ear or other feature. As another example, the accessory component  1529  may be a health-monitoring device. 
     In some implementations of the head-mounted device  1500 , some or all of these components may be included in a separate device that is removable. For example, any or all of the processor  1508 , the memory  1510 , and/or the storage device  1512 , the communications device  1514 , the sensors  1516 , the power source  1518 , and the display device  1520  may be incorporated in a device such as a smart phone that is connected (e.g., by docking) to the other portions of the head-mounted device  1500 . 
     In some implementations of the head-mounted device  1500 , the processor  1508 , the memory  1510 , and/or the storage device  1512  are omitted, and the corresponding functions are performed by an external device that communicates with the head-mounted device  1500 . In such an implementation, the head-mounted device  1500  may include components that support a data transfer connection with the external device using a wired connection or a wireless connection that is established using the communications device  1514 . 
       FIG.  17    is a side view detail that shows the headband  1506  and the accessory adjustment device  1528  in a first position.  FIG.  18    is a side view detail that shows the headband  1506  and the accessory adjustment device  1528  in a second position. 
     The accessory adjustment device  1528  includes a first end portion  1760   a , a second end portion  1760   b , and an adjuster portion  1760   c . In alternative implementations, the accessory adjustment device  1528  may include two or more of the adjuster portions. The adjuster portion  1760   c  supports the accessory component  1529  with respect to the headband  1506  and is configured to move between the first end portion  1760   a  and the second end portion  1760   b , which changes the location of the adjuster portion  1760   c  along the length direction of the headband  1506  and also changes the position of the accessory component  1529  along the length direction of the headband  1506 . 
     The first end portion  1760   a  and the second end portion  1760   b  are rigid or semi rigid structures that are connected to the headband  1506  in a fixed manner such that they are not able to move with respect to the headband  1506 . The adjuster portion  1760   c  may be a rigid or semi rigid structure that is connected to first end portion  1760   a  and the second end portion  1760   b  such that it is able to move with respect to the first end portion  1760   a , the second end portion  1760   b  and the headband  1506 . As an example, the adjuster portion  1760   c  may move to positions including and between a first position, in which the adjuster portion  1760   c  is adjacent to and/or engaged with the first end portion  1760   a , and a second position, in which the adjuster portion  1760   c  is adjacent to and/or engaged with the second end portion  1760   b . Movement of the adjuster portion  1760   c  with respect to the first end portion  1760   a  and the second end portion  1760   b  also moves the adjuster portion  1760   c  with respect to the headband  1506  and with respect to the head of a user when the user is wearing the head-mounted device  1500 . 
     The adjuster portion  1760   c  is connected to the first end portion  1760   a  and the second end portion  1760   b  to allow the adjuster portion  1760   c  to move toward and away from each of the first end portion  1760   a  and the second end portion  1760   b . As an example, the connecting structures  1762  may be structures such as rods or cables that the adjuster portions are connected to by fixed connections and/or sliding connections. Biasing structures  1764  such as compression springs or tension springs may be placed between the adjuster portion  1760   c  and each of the first end portion  1760   a  and the second end portion  1760   b  to urge the adjuster portion  1760   c  to a neutral position (e.g., centered between the first end portion  1760   a  and the second end portion  1760   b ). In implementations in which there are multiple adjuster portions, the biasing structures  1764  may also be located between adjacent pairs of the adjuster portions. 
     The adjuster portion  1760   c  is related to the first end portion  1760   a  and the second end portion  1760   b  by electromagnetic devices that that each include an electromagnet  1766   a  and a magnetic component  1766   b . The magnetic component  1766   b  may be a ferromagnetic structure that may be attracted to and/or repelled by the electromagnet  1766   a.    
     In some implementations, the electromagnetic devices are configured such that a repulsive force generated by one of the electromagnets  1766   a  relative to a respective one of the magnetic components  1766   b  is used to move the adjuster portion  1760   c  away from one of the first end portion  1760   a  or the second end portion  1760   b  and toward the other of the first end portion  1760   a  and the second end portion  1760   b . In some implementations, the electromagnetic devices are configured such that an attractive force generated by one of the electromagnets  1766   a  relative to a respective one of the magnetic components  1766   b  is used to move the adjuster portion  1760   c  toward one of the first end portion  1760   a  or the second end portion  1760   b  and away from the other of the first end portion  1760   a  and the second end portion  1760   b.    
     In the illustrated example, the adjuster portion of the headband adjustment device  1526  is initially in a neutral position by virtue of biasing forces applied by the biasing structures  1764  ( FIG.  17   ). An attractive force is then applied between the first end portion  1760   a  and the adjustment portion  1760   c  using one of the electromagnetic devices to move the adjustment portion  1760   c  toward the first end portion  1760   a  ( FIG.  18   ). As an example, the adjustment portion  1760   c  may be moved so that it is adjacent to and/or in engagement with the first end portion  1760   a  when an attractive force is applied between the first end portion  1760   a  and the adjustment portion  1760   c  using one of the electromagnetic devices. Likewise, the adjustment portion  1760   c  may be moved toward the second end portion  1760   b  so that it is adjacent to and/or in engagement with the second end portion  1760   b  when an attractive force is applied between the second end portion  1760   b  and the adjustment portion  1760   c  using one of the electromagnetic devices. 
       FIG.  19    is a top view illustration that shows a head-mounted device  1900  that includes a device housing  1902  and a headband  1906  with multiple headband connectors  1924   a ,  1924   b ,  1924   c , which are shown in a connected position. The head-mounted device  1900  is similar to the head-mounted device  100  except as otherwise noted, and may include any or all of the components described in connection with the head-mounted device  100 . In addition, the headband connectors  1924   a ,  1924   b ,  1924   c  may be added to any other of the head-mounted devices that are described herein. 
     The headband connectors  1924   a ,  1924   b , and  1924   c  are each similar to the first headband connector  124  and the second headband connector  125  and can be implemented using the previously described structures to allow each of the headband connectors  1924   a ,  1924   b ,  1924   c  to be moved between connected and disconnected positions. As an example, each of the headband connectors  1924   a ,  1924   b ,  1924   c  may include paired magnetic components that allow first and second parts of each of the headband connectors  1924   a ,  1924   b ,  1924   c  to connect and disconnect. Example of paired magnetic components include paired magnets, a magnet paired with a ferromagnetic part, and an electromagnetic paired with a ferromagnetic part. Thus, the headband connectors  1924   a ,  1924   b ,  1924   c  may each include a first magnetic component on a first part of the headband connector and a second magnetic component on a second part of the headband connector. 
     Each of the headband connectors  1924   a ,  1924   b ,  1924   c  is connected to a respective portion of the headband  1906 , to allow, for example, first and second portions of the headband  1906  to be connected and disconnected with respect to each other. 
     The locations of the headband connectors  1924   a ,  1924   b ,  1924   c  that are shown in  FIG.  9    are example. Headband connectors of the type shown and described with respect to the headband connectors  1924   a ,  1924   b ,  1924   c  can be provided on the headband  1906  in any number and at any location. 
     In the illustrated example, the headband connector  1924   a  is positioned on a first lateral side of the headband  1906 , the headband connector  1924   b  is positioned on a right lateral side of the headband  1906 , and the headband connector  1924   c  is positioned at the rear of the headband  1906 , approximately in alignment with a lateral midline of the device housing  1902 . In one implementation, the headband connectors  1924   a ,  1924   b ,  1924   c  are all included in the head-mounted device  1900  to allow multiple options for connection and disconnection of the headband  1906 . In another example, the headband connectors  1924   a , 1924   b  on the lateral sides are included and the headband connector  1924   c  on the rear of the headband  1906  is omitted. In another example, the headband connectors  1924   a , 1924   b  on the lateral sides are omitted and the headband connector  1924   c  allows connection and disconnection of the headband  1906  at the rear of the headband  1906 . 
     In one implementation, one or more of the headband connectors  1924   a ,  1924   b ,  1924   c  is added to the headband  106  of the head-mounted device  100  such that it includes an additional headband connector that is located at an intermediate location along the headband  106 . 
     A physical environment refers to a physical world that people can sense and/or interact with without aid of electronic systems. Physical environments, such as a physical park, include physical articles, such as physical trees, physical buildings, and physical people. People can directly sense and/or interact with the physical environment, such as through sight, touch, hearing, taste, and smell. 
     In contrast, a computer-generated reality (CGR) environment refers to a wholly or partially simulated environment that people sense and/or interact with via an electronic system. In CGR, a subset of a person&#39;s physical motions, or representations thereof, are tracked, and, in response, one or more characteristics of one or more virtual objects simulated in the CGR environment are adjusted in a manner that comports with at least one law of physics. For example, a CGR system may detect a person&#39;s head turning and, in response, adjust graphical content and an acoustic field presented to the person in a manner similar to how such views and sounds would change in a physical environment. In some situations (e.g., for accessibility reasons), adjustments to characteristic(s) of virtual object(s) in a CGR environment may be made in response to representations of physical motions (e.g., vocal commands). 
     A person may sense and/or interact with a CGR object using any one of their senses, including sight, sound, touch, taste, and smell. For example, a person may sense and/or interact with audio objects that create three-dimensional or spatial audio environment that provides the perception of point audio sources in three-dimensional space. In another example, audio objects may enable audio transparency, which selectively incorporates ambient sounds from the physical environment with or without computer-generated audio. In some CGR environments, a person may sense and/or interact only with audio objects. 
     Examples of CGR include virtual reality and mixed reality. 
     A virtual reality (VR) environment refers to a simulated environment that is designed to be based entirely on computer-generated sensory inputs for one or more senses. A VR environment comprises a plurality of virtual objects with which a person may sense and/or interact. For example, computer-generated imagery of trees, buildings, and avatars representing people are examples of virtual objects. A person may sense and/or interact with virtual objects in the VR environment through a simulation of the person&#39;s presence within the computer-generated environment, and/or through a simulation of a subset of the person&#39;s physical movements within the computer-generated environment. 
     In contrast to a VR environment, which is designed to be based entirely on computer-generated sensory inputs, a mixed reality (MR) environment refers to a simulated environment that is designed to incorporate sensory inputs from the physical environment, or a representation thereof, in addition to including computer-generated sensory inputs (e.g., virtual objects). On a virtuality continuum, a mixed reality environment is anywhere between, but not including, a wholly physical environment at one end and virtual reality environment at the other end. 
     In some MR environments, computer-generated sensory inputs may respond to changes in sensory inputs from the physical environment. Also, some electronic systems for presenting an MR environment may track location and/or orientation with respect to the physical environment to enable virtual objects to interact with real objects (that is, physical articles from the physical environment or representations thereof). For example, a system may account for movements so that a virtual tree appears stationery with respect to the physical ground. 
     Examples of mixed realities include augmented reality and augmented virtuality. 
     An augmented reality (AR) environment refers to a simulated environment in which one or more virtual objects are superimposed over a physical environment, or a representation thereof. For example, an electronic system for presenting an AR environment may have a transparent or translucent display through which a person may directly view the physical environment. The system may be configured to present virtual objects on the transparent or translucent display, so that a person, using the system, perceives the virtual objects superimposed over the physical environment. Alternatively, a system may have an opaque display and one or more imaging sensors that capture images or video of the physical environment, which are representations of the physical environment. The system composites the images or video with virtual objects, and presents the composition on the opaque display. A person, using the system, indirectly views the physical environment by way of the images or video of the physical environment, and perceives the virtual objects superimposed over the physical environment. As used herein, a video of the physical environment shown on an opaque display is called “pass-through video,” meaning a system uses one or more image sensor(s) to capture images of the physical environment, and uses those images in presenting the AR environment on the opaque display. Further alternatively, a system may have a projection system that projects virtual objects into the physical environment, for example, as a hologram or on a physical surface, so that a person, using the system, perceives the virtual objects superimposed over the physical environment. 
     An augmented reality environment also refers to a simulated environment in which a representation of a physical environment is transformed by computer-generated sensory information. For example, in providing pass-through video, a system may transform one or more sensor images to impose a select perspective (e.g., viewpoint) different than the perspective captured by the imaging sensors. As another example, a representation of a physical environment may be transformed by graphically modifying (e.g., enlarging) portions thereof, such that the modified portion may be representative but not photorealistic versions of the originally captured images. As a further example, a representation of a physical environment may be transformed by graphically eliminating or obfuscating portions thereof. 
     An augmented virtuality (AV) environment refers to a simulated environment in which a virtual or computer-generated environment incorporates one or more sensory inputs from the physical environment. The sensory inputs may be representations of one or more characteristics of the physical environment. For example, an AV park may have virtual trees and virtual buildings, but people with faces photorealistically reproduced from images taken of physical people. As another example, a virtual object may adopt a shape or color of a physical article imaged by one or more imaging sensors. As a further example, a virtual object may adopt shadows consistent with the position of the sun in the physical environment. 
     There are many different types of electronic systems that enable a person to sense and/or interact with various CGR environments. Examples include head-mounted systems, projection-based systems, heads-up displays (HUDs), vehicle windshields having integrated display capability, windows having integrated display capability, displays formed as lenses designed to be placed on a person&#39;s eyes (e.g., similar to contact lenses), headphones/earphones, speaker arrays, input systems (e.g., wearable or handheld controllers with or without haptic feedback), smartphones, tablets, and desktop/laptop computers. A head-mounted system may have one or more speaker(s) and an integrated opaque display. Alternatively, a head-mounted system may be configured to accept an external opaque display (e.g., a smartphone). The head-mounted system may incorporate one or more imaging sensors to capture images or video of the physical environment, and/or one or more microphones to capture audio of the physical environment. Rather than an opaque display, a head-mounted system may have a transparent or translucent display. The transparent or translucent display may have a medium through which light representative of images is directed to a person&#39;s eyes. The display may utilize digital light projection, OLEDs, LEDs, uLEDs, liquid crystal on silicon, laser scanning light source, or any combination of these technologies. The medium may be an optical waveguide, a hologram medium, an optical combiner, an optical reflector, or any combination thereof. In one embodiment, the transparent or translucent display may be configured to become opaque selectively. Projection-based systems may employ retinal projection technology that projects graphical images onto a person&#39;s retina. Projection systems also may be configured to project virtual objects into the physical environment, for example, as a hologram or on a physical surface. 
     As described above, one aspect of the present technology is the gathering and use of data available from various sources for use during operation of a head-mounted device. As an example, such data may identify the user and include user-specific settings or preferences. The present disclosure contemplates that in some instances, this gathered data may include personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, twitter ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, or any other identifying or personal information. 
     The present disclosure recognizes that the use of such personal information data, in the present technology, can be used to the benefit of users. For example, a user profile may be established that stores information that allows the head-mounted device to be actively adjusted for a user. Accordingly, use of such personal information data enhances the user&#39;s experience. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users, and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the US, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA); whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, in the case of storing a user profile to adjustment of a head-mounted device, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In another example, users can select not to provide data regarding usage of specific applications. In yet another example, users can select to limit the length of time that application usage data is maintained or entirely prohibit the development of an application usage profile. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an app that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing such personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. For example, adjustment parameters may be determined each time the head-mounted device is used, such as by sensing forces applied to parts of the head-mounted device when it is worn by the user, and without subsequently storing the information or associating with the particular user.

Metadata:
Filing Date: 20210128
Publication Date: 20231107
Grant Date: 20231107
Priority Date: 20200325
Inventors: KASAR, DARSHAN R.
MENDEZ, JAVIER
SOLDNER, NICHOLAS C.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01F7/064", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16M13/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F7/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F7/20", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/163", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B7/002", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01F7/064", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0176", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16M13/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/163", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F7/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F7/20", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 74853715