This morning Apple analyst Ming-Chi Kuo tweeted out a quick supply chain research note stating that that "IQE is set to replace Landmark as the exclusive supplier of epi-wafer for proximity sensors in the iPhone 15 series.

While all iPhone 15 models will adopt a similar Dynamic Island design as the iPhone 14 Pro, the difference lies in the placement of the proximity sensor. In the iPhone 14 Pro, the proximity sensor was located under the display (outside the dynamic island). Conversely, in the iPhone 15 series, the proximity sensor is situated within the dynamic island, with almost no change to the Dynamic Island area.

Due to this change, Finisar (acquired by Coherent/II-VI) will shift to offering 940nm wavelength proximity sensors (compared to 1380nm for the iPhone 14 Pro), and the upstream epi-wafer supplier will transition to IQE."

The main purpose of a proximity sensor is to measure how close the sensor device is to a particular target. In relation to the iPhone, this proximity sensor helps the iPhone screen switch off as soon as the user moves their phone closer to their ear.

As a side note, it should be noted that Apple has at least two proximity sensor patents (01 and 02) that relate to hand-tracking technology when in use with finger device accessories as noted in one patent figure below from a March 9, 2023 patent report.

Hand and eye tracking was presented in an Apple patent that we covered yesterday titled "Apple Reveals Next-Gen Eye and Hand-Tracking to assist users work in 3D Environments on Macs, XR Headset, an iPad & more." The patent listed "proximity sensors" as one of the key sensors that will allow for hand-tracking with iDevices, including iPhones.  

Whether this is something that could be introduced later this year and/or be a partial reason for Apple changing proximity sensor suppliers is not known at this time. Yet the switch to a new supplier may certainly point to a future development in-the-works.  

Lastly, Kuo noted that "Power Integrations is also the main winner of Apple's marked increase in shipment forecasts for 20W USB-C chargers, thanks to the transition to USB-C in the iPhone 15 series. Power Integrations exclusively supplies the main chip of 20W USB-C charger customized for Apple."