Hi, very similar to QR code, but I know that it doesn't read QR code (confirmed in developer labs). And I know it reads Vision Code. One example is if you order it with zeiss lens, it comes with a vision code, like in below: https://www.zeiss.com/vision-care/us/myzeiss-vision.html And this article explains a bit more about the vision code and where it is originated from: https://ar-code.com/blog/apple-vision-pro-codes-the-future-of-ar-and-qr-codes-on-visionos

Hi, sorry, but I don't seem to find anything related to vision code?

Yup, I think it is not directly related to my question, but thanks! And upon further testing, we figured out that the hand tracking actually does capture data from with facedown cameras.