An Apple patent reveals how certain Watch Bands don't interfere with the Compass due to a 'Distortion Shield' & more
In 2019 Apple Watch users began complaining about the compass on their Apple Watch not functioning properly. Apple responded by posting a warning about certain watch bands affecting the Apple Watch magnetometer as presented in-part below. Apple's support page also provided a walkthrough the Apple Watch settings to reset the compass.
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Yesterday the US Patent & Trademark Office published a patent application from Apple titled "In-Field Soft Magnetic Distortion Hardware Compensation." As Apple noted in their warning about certain bands affecting the magnetometer / compass, they also specifically noted that the compass wasn't affected by Sport Loop bands introduced in September 2019 or later, or any version of the Sport Band.
Apple's patent published yesterday explains some of the changes that were made to the magnetometer and construction of the Apple Watch, including a new 'distortion shield.' The magnetometer's new shield and other improvement could together work around "soft distortion" brought on by certain materials in certain watch bands. Apple's patent walks us through this matter. Below are just a few paragraphs in a sea of details.
In some examples, the device can detect the change in the component by detecting a change in the magnetic distortion associated with the component, such as through the magnetometer.
In some examples, the device can detect the change in the component through one or more sensors that can be configured to detect whether a component is attached to the device.
For example, a proximity sensor can detect when a component is near to, adjacent to, and/or attached to the device. In some examples, a removably attachable component can provide a signal to the device indicating that is has been attached thereto, and the device can detect the change in magnetism based at least partially on this indication.
For example, a band can include a contact portion that can come into electrical contact with one or more components of the device when the band is attached to the device, thereby providing an indication to the device and allowing for detection of the change in magnetism associated with the component.
In some examples, the component can wirelessly, or otherwise without contact, provide a signal to the device indicating proximity or attachment of the component. For example, a removably attachable component can include an RFID tag that can provide a radio frequency signal to the device indicating that the component has been attached thereto.
In some examples, detecting the change in magnetism can include prompting a user and receiving an input or response from the user based on the prompt indicating that a change in components and/or magnetism of the device has occurred.
For example, the device can prompt the user through a user interface to indicate whether there has been a change in a component of the device, such as the band.
In some examples, the user can indicate that a magnetism and/or a component of the device has changed without a prompt, such as by navigating to a menu of the device, thereby allowing the device to detect the change in magnetism associated with the change in component through the user's input.
Apple's patent FIG. 3 illustrates a view of the magnetometer #160 and its position in the internal volume of an Apple Watch; Apple's patent FIGS. 10A and 10B provide a larger view of the Apple Watch magnetometer, distortion shield and where the band attachment is in relation to the magnetometer.
Apple's patent FIGS. 8 and 9 show different process flow diagrams for a method of calibrating a magnetometer of an electronic device.
For finer details, review Apple's patent application number 20210072335. Considering that the patent was filed well after the issue arose in 2019 with certain watch bands, there's a chance that some of what Apple details in their partial solution (patent) are yet to be implemented in Apple Watch.
Considering that this is a patent application, the timing of any new feature coming to market is unknown at this time.