Apple Apple Watch 'high precision' temperature sensor patent revealed

Apple has been granted a patent for a "high precision" temperature sensor for the Apple Watch. In a few weeks, Apple is expected to launch the new Apple Watch Series 8 with body temperature sensing.

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MyHealthyApple has discovered this newly granted Apple patent, filed with the US Patent and Trademark Office, titled "Temperature gradient sensing in electronic devices". It is entitled "Temperature gradient sensing in electronic devices".) While the wording of the patent suggests that it could be applied to any device, the only device depicted in the patent illustration is apparently the Apple Watch, which may hint at Apple's specific application of the technology.

Apple's patent protection shows an electronic device enclosure that contains a temperature sensing system comprising a temperature sensor and a temperature difference probe. The system works by calculating the difference between the two ends of the probe. One end touches the surface to be measured and the other end is connected to the temperature sensor. The voltage difference between the different ends of the probe can then be correlated with the temperature difference measurement.

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

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