Apple has been granted a new patent for a temperature sensor suitable for the Apple Watch, just weeks before the company unveils the Apple Watch Series 8, which is said to have body temperature sensing capabilities. One more clue?

The newly granted patent, spotted by MyHealthyApple, has been filed with the United States Patent and Trademark Office and is entitled “Temperature gradient sensing in electronic devices”. While the wording of the patent suggests it can apply to any device, the only product depicted in the patent illustrations is clearly the Apple Watch, which could hint at what specific app Apple has in mind for it. this technology.

Apple’s patent refers to an electronic device housing that houses a temperature sensing system comprising a temperature sensor and a differential temperature probe. The system works by calculating the difference between the two ends of a probe. One end touches the surface to be measured, while the other is connected to a temperature sensor. The voltage difference between the two 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 probe may 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, internal or external, of the electronic device… In this construction, the temperature sensor can be configured to measuring 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. Clearly, it indicates that the sensor can be used to measure the “absolute temperature” of an external surface, such as the skin.

Most notably, Apple explicitly mentions how the location of the external probe can be located on a “surface such as the back crystal of a smartwatch” and says the system includes a “high-precision, high-performance absolute temperature sensor. exactness.” The patent describes several potential shapes and layouts for the temperature sensor, one of the most striking designs being a cross-shaped temperature probe.

According to analyst Ming-Chi Kuo, Apple originally intended to offer a body temperature feature with the Apple Watch 7 models, but the company scrapped its plans due to the algorithm that failed to meet the requirements during the Engineering Validation Testing (EVT) phase last year.

The problems Apple has encountered are believed to be that skin temperature varies rapidly depending on the environment, and since a smartwatch cannot monitor core body temperature using hardware, this feature is highly dependent on the environment. an algorithm that produces accurate results. This patent only covers the hardware configuration of a temperature sensing system, not the algorithm required to produce accurate results.

If patents don’t guarantee enforcement in the near future, then it’s hard to ignore the plethora of reports of the Apple Watch Series 8 offering a body temperature sensor. Besides Kuo, Bloomberg’s Mark Gurman says the body temperature sensor will help with fertility planning, giving women insight into their ovulation cycle. Apple has been emphasizing women’s health in recent years, so the expansion of features in this area seems to be in line with the company’s goals.

Additionally, the body temperature sensor could be used to improve pattern detection when tracking sleep. Apple has leveraged sleep blood oxygen detection capabilities from Apple Watch Series 6 and significantly beefed up Apple Watch sleep tracking in watchOS 9, which means further improvements in this area aided by the material this year seem very plausible.

Apple is also reportedly planning to enable the body temperature sensor to detect when a user has a fever, but it seems unlikely that this feature will be available when the Apple Watch Series 8 launches. In any case, we can expect three new models, including a “rugged” version that would offer a new design (but at a higher price). An Apple Watch 8 Pro…