For at least five years, Apple has been researching how it can measure the health of an Apple Watch wearer non-invasively and conveniently, in research that could be applied to the Apple Vision Pro, too.
Apple's patent describes a band that could conduct, or assist, with ECG measurements, amongst other benefits
has been developing a new activity band for the Apple Watch, and optionally other devices, that would be made of stretchable fabric, and conduct health measurements including blood pressure. Back in 2019, it was granted a patent called "Fabric-based items with stretchable bands."
In November 2024, it was granted the same patent again. Apple applied for a patent on this version in 2022, but the filing also refers to a 2020 edition.
So this isn't some idle pet project of someone in the Apple Watch division at Apple Park, it is continued effort to explore a topic. It might not be the most productive exploration, though, as it's hard to even spot the differences between the different patents and patent applications.
Each of them describe methods in which circuitry may be utilized within such an item of wearable technology.
"The stretchable band may be formed from a ring-shaped strip of stretchable fabric having an opening configured to fit around a body part of a user," says the new version. "Circuitry may be coupled to strands of material in the stretchable band."
"The circuitry may include sensor circuitry for making measurements on the body part such as electrocardiogram measurements, blood pressure measurements, and respiration rate measurements," it continues. "A coil formed from conductive strands in the fabric-based item may be used by wireless power receiving circuitry in the fabric-based item to receive the wireless power."
While the most obvious use for such a band would be a future version of the Apple Watch, Apple has repeatedly been careful to specify broader applications. Since the first versions of this patent were filed, though, the Apple Vision Pro has been revealed and it's now easy to see the allusions to it.
"As examples," says the patent, "a wrist band with elastic fabric, a head band with elastic fabric, or other wearable item that includes elastic fabric (e.g., a hat, an undergarment worn on a user's torso or lower body, a shirt, pants, shorts (e.g., bicycle shorts, board shorts, or other snugly fitting clothing), yoga clothing or other athletic attire, an arm band, an elastic belt, a sock, a glove, etc."
Detail from Apple's patent showing a ring-shaped wearable band
Claims within the patent also specify certain materials, including nylon and spandex, plus whether the band may have electrodes for its electrocardiogram sensor.
Apple's patent also notes that there are issues around any wearable technology and its reliability in regular use.
"If care is not taken, fabric-based items such as these may not offer desired features," says. "For example, a fabric-based item with sensing circuitry may not be able to gather measurements accurately, may not be able to interact with external equipment effectively, or may be difficult for a user to keep clean."
Consequently, Apple's patent details how such a band could survive any necessary cleaning.
"The fabric-based item may be configured to sustain relatively high temperatures such as those associated with laundering of clothing," it says. "For example, the fabric-based item may have supercapacitors for energy storage and other electrical components that can be laundered in hot water and dried in a clothes dryer without damage."
Third-party firms have previously attempted to produce Apple Watch bands that provide extra battery power, until changes in Apple's design made that impossible.
The patent is credited to seven inventors. All seven also comprise the complete list of inventors on a 2020 patent to conceal batteries within an Apple Watch band.