It is generally believed that augmented reality includes the application of digital images to superimpose images from the real world to create the illusion that an object in the world does not really exist. In the vast majority of cases, this will involve some kind of display mechanism, which will be located between the user’s eyes and the real world, but in a special case, head display is not used at all. < p > < p > Apple ar efforts initially included a glasses or headless version that projected data onto real-world objects, including the concept that users wear the projector itself. In a patent granted to Apple by the U.S. patent and Trademark Office on Tuesday called & quot; a method and system for projecting digital information onto real objects in the real world & quot;, apple canceled the screen and instead applied digital images to real-world objects themselves. < / P > < p > although some patent descriptions seem quite simple, they use some form of projector to project images onto a physical surface. However, in order to map the digital image to the object correctly, the system also uses other sensors to detect the environment and objects. The system captures the image that it wants to map the projection to the real world object. The image data is combined with the information from the depth sensor to create the depth map of the object. This is used to calculate the spatial transformation between virtual data and real objects, which can then be used by applications to plan which pixels to project to where. < / P > < p > Apple has proposed a camera system with a depth sensor and a projector for real-world screenless ar. Apple didn’t mention what kind of depth sensor to use, but mentioned using infrared projectors and infrared cameras, which would be similar to the truedepth camera array feature in the modern iPhone. < / P > < p > depth mapping also includes estimating the 3D position of an object, as well as the application position of digital information on the object, and the relationship between the projector and the user. In this way, 3D effects can be generated on the superimposed images, which are best calculated based on the perceived viewing position of the user. By generating subsequent images and depth maps, the system will be able to counteract any vibration or movement of the projector, so that the illusion of projection remains unchanged under such changes. < / P > < p > although the idea of casting light on objects is not new and has been used for artistic and commercial purposes for many years, Apple’s patent mainly involves the need to calibrate the projection repeatedly to make it as accurate as possible. It is understood that this could include projecting data from the car onto a surface, such as a speedometer on the windshield, which ideally needs to be calibrated continuously to maintain user readability. Global Tech