'High-Accuracy' Apple Watch Temperature Sensor Revealed by Patent Filing Just Weeks Before Series 8 Unveiling

Apple has been granted a patent for a temperature sensor suitable for the Apple Watch, just weeks before the company is expected to unveil the Apple Watch Series 8 with body temperature sensing capabilities.

Apple Watch Body Temperature Finished
The newly granted patent, spotted by MyHealthyApple, was filed with the United States Patent and Trademark Office and is titled "Temperature gradient sensing in electronic devices." While the wording of the patent suggests that it can apply to any device, the only device depicted in the patent's illustrations is clearly the Apple Watch, potentially hinting what specific application Apple has in mind for the technology.

apple watch temperature sensor patent
Apple's patent protects an electronic device housing that encloses a temperature sensing system comprising a temperature sensor and a differential temperature probe. The system works by calculating the difference between two ends of a probe. One end touches the surface to be measured, while the other is connected to a temperature sensor. The difference in voltage across the different ends of the probe can then be correlated to a differential temperature measurement.

The temperature probe is configured to generate a voltage corresponding to a temperature gradient between a first end of the probe and a second end of the probe. The temperature sensor can be disposed within an electronic device housing. A first end of the probe can be coupled to the temperature sensor and a second end of the probe can be coupled to any suitable surface, whether internal or external, of the electronic device... In this construction, the temperature sensor can be configured to measure a temperature, at any given sampling time or sampling rate, of any surface or volume to which the sensing surface is exposed.

The patent goes on to explain in technical detail how the temperature sensing hardware works. Crucially, while the patent covers how a dedicated temperature sensor could be used inside a device to monitor the temperature of a component like the processor, it says that the sensor can be used to measure "absolute temperature" of an external surface, such as skin.

Most notably, Apple explicitly mentions how the location of the external probe may be located on a "back surface such as a back crystal of a smart watch" and says the system includes a "high-precision and high-accuracy absolute temperature sensor." The patent outlines several potential shapes and arrangements for the temperature sensor, with one of the more striking designs being a cross-shaped temperature probe.

apple watch temperature sensor patent 2
According to Apple analyst Ming-Chi Kuo, Apple originally intended to offer a body temperature measurement feature with the ‌Apple Watch Series 7‌ models, but the company shelved the plans when the body temperature algorithm it had developed failed to meet requirements before the device entered the engineering validation testing (EVT) phase last year.

The problems Apple has experienced relating to body temperature measurement purportedly relate to the fact that skin temperature quickly varies based on the environment, and since a smartwatch cannot monitor core body temperature using hardware, the feature is heavily dependent on an algorithm that produces accurate results. This patent only covers the hardware setup for a temperature sensing system, rather than the algorithm required to produce accurate results.

While Apple's patent filings cannot be taken as concrete evidence of the company's exact plans since many of its patents are never used, they do show its areas of research and development, and sometimes reveal impending products, such as the AirTag.

In this case, it is difficult to look past the plethora of reports about the Apple Watch Series 8 offering a body temperature sensor – something that has long been rumored by sources like Kuo. Reports indicate that while the device is unlikely to offer exact body temperature measurements, the sensor will be used to provide at least two new health monitoring features.

The Wall Street Journal and Bloomberg's Mark Gurman state that the body temperature sensor will aid fertility planning, giving women insights into their ovulation cycle. Apple has focused on women's health in recent years, so expanding features in this area seems to be in line with the company's objectives.

Moreover, the body temperature sensor could be used to improve the detection of patterns when tracking sleep. Apple leveraged blood oxygen sensing capabilities during sleep starting with the Apple Watch Series 6 and significantly bolstered the Apple Watch's sleep tracking in watchOS 9, meaning that further improvements in this area aided by hardware this year seem very plausible.

Apple is also said to have plans to enable the body temperature sensor to detect when a user has a fever, but it seems unlikely that this feature will be available upon the launch of the Apple Watch Series 8. Gurman believes that further in the future, Apple Watch models could determine if a user has a higher than normal body temperature, but it is still unlikely to show an exact measurement.

Related Roundup: Apple Watch Series 9
Tag: Patent
Buyer's Guide: Apple Watch (Neutral)

Top Rated Comments

polyphenol Avatar
21 months ago

A simple $7 thermometer from Walmart or Target placed under the tongue or armpit can provide better results.

It’s gimmicky at first but yes this new feature will eventually improve…albeit in the slow yearly Apple software improvement fashion.
The big thing is that a watch, being worn substantially all the time, will take repeated measurements, store them and allow for comprehensive analysis - taking into account the other measurements it can make. For example, temperature might right to "normal" when walking briskly, exercising, etc., but drop in the middle of the night while asleep. Put those pixels together and get a picture.

A $7 thermometer doesn't give you all that.
Score: 24 Votes (Like | Disagree)
BootsWalking Avatar
21 months ago
'High-Accuracy' Apple Watch Temperature Sensor Revealed by Patent Filing Just Weeks Before Series 8 Unveiling
...
Apple Watch models could determine if a user has a higher than normal body temperature, but it is still unlikely to show an exact measurement.

Huh?
Score: 13 Votes (Like | Disagree)
WWPD Avatar
21 months ago
This will be great for revealing who are vampires.
Score: 12 Votes (Like | Disagree)
Cromulent Avatar
21 months ago
I will get the Series 8 as my first ever Apple Watch, so this is rather exciting to see.
Score: 11 Votes (Like | Disagree)
polyphenol Avatar
21 months ago
Everyone seems to walk right past the issue of lower than "normal" temperature. Which can be every bit as important as higher than "normal" temperatures.

Especially obviously for those with thyroid issues. Hypothyroidism is well-known for resulting in low blood temperature and even just being slightly under-dosed can have an impact on temperature.

While not what we'd really like, a good temperature measurement which can detect lowered as well as raised temperatures would be a welcome addition.
Score: 10 Votes (Like | Disagree)
TheYayAreaLiving ?️ Avatar
21 months ago
Woo hoo! At least, we’re trying a new temperate sensor. I’ll take it. Apple should never release new Apple watches without adding any type of sensors in a year.

If we’re going to pay the premium price it has to offer premium features too. Software and hardware-wise.
Score: 10 Votes (Like | Disagree)

Popular Stories

reset password request iphone

Warning: Apple Users Targeted in Phishing Attack Involving Rapid Password Reset Requests

Tuesday March 26, 2024 4:34 pm PDT by
Phishing attacks taking advantage of Apple's password reset feature have become increasingly common, according to a report from KrebsOnSecurity. Multiple Apple users have been targeted in an attack that bombards them with an endless stream of notifications or multi-factor authentication (MFA) messages in an attempt to cause panic so they'll respond favorably to social engineering. An...
maxresdefault

Apple to Launch New iPad Pro and iPad Air Models in May

Thursday March 28, 2024 11:07 am PDT by
Apple will introduce new iPad Pro and iPad Air models in early May, according to Bloomberg's Mark Gurman. Gurman previously suggested the new iPads would come out in March, and then April, but the timeline has been pushed back once again. Subscribe to the MacRumors YouTube channel for more videos. Apple is working on updates to both the iPad Pro and iPad Air models. The iPad Pro models will...
Generic iOS 18 Feature Purple

iOS 18: What to Expect From 'Biggest' Update in iPhone's History

Wednesday March 27, 2024 11:10 am PDT by
At least some Apple software engineers continue to believe that iOS 18 will be the "biggest" update in the iPhone's history, according to Bloomberg's Mark Gurman. Below, we recap rumored features and changes for the iPhone. "The iOS 18 update is expected to be the most ambitious overhaul of the iPhone's software in its history, according to people working on the upgrade," wrote Gurman, in a r...
maxresdefault

Apple Announces WWDC 2024 Event for June 10 to 14

Tuesday March 26, 2024 10:02 am PDT by
Apple today announced that its 35th annual Worldwide Developers Conference is set to take place from Monday, June 10 to Friday, June 14. As with WWDC events since 2020, WWDC 2024 will be an online event that is open to all developers at no cost. Subscribe to the MacRumors YouTube channel for more videos. WWDC 2024 will include online sessions and labs so that developers can learn about new...
apple maps 3d feature

Apple Maps May Gain Custom Routes With iOS 18

Tuesday March 26, 2024 3:10 pm PDT by
Apple may be planning to add support for "custom routes" in Apple Maps in iOS 18, according to code reviewed by MacRumors. Apple Maps does not currently offer a way to input self-selected routes, with Maps users limited to Apple's pre-selected options, but that may change in iOS 18. Apple has pushed an iOS 18 file to its maps backend labeled "CustomRouteCreation." While not much is revealed...
General iOS 17 Feature Orange Purple

Apple Releases Revised Versions of iOS 17.4.1 and iPadOS 17.4.1 With Updated Build Number

Wednesday March 27, 2024 5:59 am PDT by
Apple on late Tuesday released revised versions of iOS 17.4.1 and iPadOS 17.4.1 with an updated build number of 21E237, according to MacRumors contributor Aaron Perris. The updates previously had a build number of 21E236. The revised updates are available for all iPhone and iPad models that are compatible with iOS 17 and iPadOS 17, but they can only be installed via the Finder app on macOS...
applephilschiller

Apple's Phil Schiller Works 80 Hours a Week Overseeing App Store

Wednesday March 27, 2024 2:03 pm PDT by
With the App Store and app ecosystem undergoing major changes in the European Union, The Wall Street Journal today shared a profile on App Store chief Phil Schiller, who is responsible for the App Store. Though Schiller transitioned from marketing chief to "Apple Fellow" in 2020 to take a step back from Apple and spend more time on personal projects and friends, he is reportedly working...