Apple Apple Watch 'high precision' temperature sensor patent revealed

Most notably, Apple explicitly mentions the location of an external probe that could be located "on the back, such as the back crystal of a smartwatch" and says that the system includes a "high precision and high accuracy absolute temperature sensor". The patent outlines several potential shapes and arrangements of temperature sensors, with one notable design being a cross-shaped temperature probe.

According to analyst Ming-Chi Kuo, Apple originally intended to offer temperature measurement on the Apple Watch Series 7 device, but shelved the plan during the engineering verification testing (EVT) phase when the developed temperature algorithm failed to meet the requirements.

The problems Apple encountered with temperature measurement were allegedly related to the fact that skin temperature can change rapidly depending on the environment, and because the smartwatch cannot use hardware to monitor core body temperature, the feature relies heavily on algorithms that produce accurate results. The patent only covers the hardware setup of the temperature sensing system, not the algorithms required to produce accurate results.

While Apple's patent applications cannot be seen as concrete evidence of the company's exact plans, as many of its patents have never been used, they do show the direction of its research and development areas and sometimes reveal exactly what products are coming, such as the AirTag tracker.

There have been many previous revelations about the Apple Watch Series 8 offering a body temperature sensor. Reports suggest that while the device is unlikely to offer accurate temperature measurements, the sensor will be used to provide at least two new health monitoring features.

Mark Gurman of the Wall Street Journal and Bloomberg said that the temperature sensor would help with fertility planning by giving women an idea of their ovulation cycle. Apple has focused on women's health in recent years, so expanding functionality in this area seems to fit the company's goals.

In addition, the temperature sensor could be used to improve the detection of patterns when tracking sleep. Apple began utilising blood oxygen sensing during sleep with the Apple Watch Series 6 and significantly enhanced Apple Watch sleep tracking in watchOS 9, meaning that this year could see further improvements in this area with the help of hardware.

Apple also plans to allow temperature sensors to detect when a user has a fever, but it seems unlikely that this will be available with the launch of the Apple Watch Series 8. Gurman believes that further down the line, Apple Watch models will be able to detect if a user's body temperature is higher than normal, but it is still unlikely to show an accurate indication. However, it is still unlikely that an accurate measurement will be displayed.