When we talk about immersive reality, we often hear about Virtual Reality and Augmented Reality. If you are on this site, you probably already know the meaning of both terms: virtual reality is able to teleport you into a cybernetic world completely disconnected from the real one you are in (it is the video game technology, like Fallout 4 VR), while augmented reality shows virtual elements superimposed on the real world (do you remember Pokémon Go?). But what is Mixed Reality
There is a lot of confusion both about the definition to be given to these terms and about the applications that derive from them. We find different interpretations. Let us try to focus on the three that we believe to be the most widespread at the time of writing.
The first one, moreover the one I personally prefer, indicates that Mixed Reality is any technology that combines real elements with virtual elements. This classification follows the famous " Reality-Virtuality continuum " theorized at the same time by Milgram and Kishino, which shows that there is a spectrum of technologies that goes from pure real reality to pure virtual reality.
Simplified scheme of Reality - Virtuality Continuum, Milgram and Kishino in 1994 (credits Wikipedia)
According to this classification, everything that is a little more virtual than real reality or a little more real than virtual reality, can be called Mixed Reality. In other words, it is sufficient to contaminate the real reality or virtual reality to obtain a mixed reality: just as the name "mixed reality" indicates, the MR (as is often abbreviated) is a mixture of the real and the virtual. Nothing to complain.
Some examples can certainly help to better understand both the definition of Mixed Reality and the meanings that it manages to take in multiple circumstances. In fact, on the continuum of Milgram and Kishino we meet the following realities:
- Augmented reality: shows virtual elements superimposed on the real world, of digital layers able to add contextual information. The case of Pokemon Go represents its most famous consumer applications so far.
- Increased virtuality: when real elements are shown above a purely virtual world (the dual of what happens in augmented reality), virtuality is increased. It is the case of one's own hands (the real ones, not the hands of a digital avatar) within a virtual universe, able to interact with it;
- Videos in mixed reality: the most effective way to show the content of an application in virtual reality is to create a video in which you see the user immersed in a virtual application. The user's image is captured by the video stream (real) of a camera, while the virtual world is the one rendered by the computer. There is a co-presence of real reality and virtual reality. The more attentive reader will have noticed that we are talking about a case of increased virtuality;
- The modified reality: the user is shown the world around him, suitably modified with respect to what appears in reality. These changes can be of various kinds:
- Punctual: some objects are removed from the scene (eg a table that is in the middle of the room is deleted), others are added (eg a virtual guide is added), the characteristics of others are changed again (eg. a girl is shown blonde even though she actually has black hair);
- Global: reality is shown, but in a completely different way than it normally appears. For example in the Beat Reality disco application, the surrounding reality is shown as a set of pulsating edges to the rhythm of music: this means that you can still see the reality that we have around, but the way it will be seen will be different from the typical human vision.
These simple examples are enough to make us understand how the potential of mixed reality is boundless and above all applicable in many areas. Thanks to its ability to creatively modify reality, mixed reality is highly appreciated in the artistic field, but it is not disdained by education, industrial training, medical, rather than in many media and entertainment applications. For this reason, all the brands that produce viewers and devices, starting with Oculus, HTC, and Google, are investing huge amounts in this technology. It is a fact that all standalone displays currently or soon on the market will offer mixed reality features.
Besides the Virtuality Continuum of Milgram and Kishino there are other definitions of Mixed Reality. A second definition of mixed reality is actually very close to that, more canonical, of augmented reality, of which it would be a special case. A second definition would indeed like mixed reality as an augmented reality in which there are interactions between virtual elements and the surrounding environment. According to this point of view, augmented reality shows information or objects over the real world, without relating directly to the real world. This would rather happen in mixed reality. A practical demonstration of this concept is given by the technologies of Magic Leap
The Magic Leap demo effectively conceptualizes this alternative definition of mixed reality: imagine that you have an augmented reality glasses and then see a virtual basketball placed on a table. If, by touching this ball, it does not move, or simply moves on a horizontal plane (ie it is not able to understand what is happening in the surrounding environment), then such a ball is displayed in augmented reality. There is another possibility, when the same ball, once struck, arrives at the edge of the table and falls on the floor, starting to bounce on everything it encounters along its way. In this case, we are talking about mixed reality, as the virtual ball is interacting with the real environment, perceiving it and being able to adapt its behavior according to it.
In short, according to this definition, mixed reality is nothing more than an interactive augmented reality.
A third definition is the one used by Microsoft, which sells its virtual reality viewers as "Windows Mixed Reality headsets". The reason why the mixed reality nomenclature is used is even misleading, as these viewers are of pure virtual reality. In addition to these purely linked to aspects such as branding and marketing, Microsoft's immersive reality platform, based on Windows 10, will probably also include augmented reality applications, and in that case we would find that coherence with the definitions of reality that today it seems to be lacking in the ecosystem developed by the Redmond giant. Whether it is an advance on time or a name coined to differentiate one's offer from the more generic expression of virtual reality, we will find out by living in short.
Windows Mixed Reality viewers can count on a particularly large fleet, with manufacturers such as Samsung, HP, Lenovo, Dell, and Acer (Microsoft credits)
We reiterate, at the time of writing, as offered by Microsoft with Windows Mixed Reality has nothing to do with the theoretical definitions of mixed reality. So don't be misled: the viewers on the market with the Mixed Reality brand are simple virtual reality viewers. The situation is different for Microsoft Hololens, able to integrate real and virtual elements into the vision.
As you can see, there is a lot of confusion about the term "mixed reality" and the same experts in the field are still debating its meaning and often we are divided between the people who give it the meaning number one (virtuality continuum) and those that give it the number two (interactive augmented reality). Regarding the number three (Windows Mixed Reality), there is a general consensus that Microsoft has used a misleading name, at least for the moment.
We hope not to have further confused you with the ideas, but rather to have offered those useful ideas to make some clarity so that you can better interface with the magical world of mixed reality.