Spatial computing has been a popular technical topic for some time. After more than a decade of research, commercial products practicing spatial computing are now finally coming to the market. As we transition from the pure digital objects on desktop and mobile screens into blending physical objects with them, many user interface, computing and software engineering paradigms must be reimagined. As opposed to the shift from desktop to mobile, the transition from the basic 2D screen regime to 3D Digital+ Physical world needs more fundamental rethinking including “object depth” as a significant parameter. This paper focused on how CAPTCHA will need to be reimagined in the new Spatial Computing world.