Whereas barcodes are scanned using a narrow beam laser, QR codes were designed to be scanned using image sensors. This means that any camera with the appropriate software can become a QR scanner.

For example, the illustration below was output with Stable Diffusion. Embedding 3 alignment markers transforms it into an image that can be read by a QR code reader.

An AI-generated image of an anime-style woman that also functions as a working QR code. If you have trouble reading it, try positioning your camera farther away from the image.