The history of immersive environments was strikingly presented in 2010 by van Krevelen and Poelman, as a continuation of the work of Tamura. Here we find the main prototypes as well as their technical progression articulated in terms of placement within the famous theoretical continuum “Reality / Virtuality”, as invented in the 1990s by Milgram and Kishino. But, if the philosophical speech involves the ontological status of the objects, the scientific basis that led to the technological achievements, exploits the resources of the philosophy of appearance, of perception and of the gnosic status of the percepts that different devices provide. Indeed, the method of 3D “look oriented” (see-through) refers to the long tradition of the philosophy of perception initiated by Brentano, Stumpf and Husserl, taken up by the psychologists of form and systematized in the cognitive approach used by cognitive scientists of the environment, such as Gibson, and of vision, such as Marr.