This application provides example multi-focal-plane image generation apparatuses, example head-up display apparatuses, example methods, and example devices. One example apparatus includes a pattern generation device and a focal length adjuster. The pattern generation device is configured to generate a light beam that carries image information, and irradiate the light beam to a surface of the focal length adjuster. The focal length adjuster is configured to perform focal length adjustment on the light beam that is irradiated to the surface of the focal length adjuster to generate a plurality of focal planes of the multi-focal-plane image generation apparatus.