AR, MR, XR or VR?
To understand what AR – Augmented Reality, MR – Mixed Reality , XR – Cross reality and VR – virtual reality actually are and the differences between them, its best to understand what each one does and where it came from, so, going furthest back, we begin with the advent of the first virtual reality systems.
Virtual Reality (VR) is an artificial environment which seeks to synthetically introduce stimuli to your senses. This means that one’s sight, sound, touch, smell and even taste can be artificially stimulated.
The Sensorama Machine, invented in 1957 then patented in 1962 was the first interactive film experience in which viewers were invited to watch a film which would use all of their senses. This multi-sensory experience was also the first ‘3D film’, designed for a single viewer and enabled the viewer to become immersed through multiple sense in the media. For example, he used an oscillating fan so that the viewer could feel the wind blowing on their face.
The first HMD that we would recognize was built by Ivan Sutherland in 1968 with the help of his students and was nicknamed the ‘Sword of Damocles’ as it was so heavy it had to be suspended from the ceiling by a metal pole.
By today’s standards, it seems rather primitive, only displaying wireframe models for graphics and no text at all.
The first modern style HMD was named “The Datavisor“ and was able to display graphics and text from computers of the day.
And it looked awesome. It literally looks like the images are being piped into your brain via the eyes. This has to go down as the most cyberpunk looking VR head-mounted display ever.
From this point in VR’s history, it is ‘just’ resolution and fidelity boosts to get to our modern consumer-based headsets. We can see many peripherals and equipment that was created in the 90’s that foreshadowed our systems today with life-size accessories and controller methods to further immerse the content consumer in the scene. Unfortunately, due to the primitive state of graphics at this point in time, the full benefit of such systems had yet to be realized:
Augmented reality (AR) is a technology that layers virtual enhancements atop our existing reality. AR is developed into apps and used on mobile devices to blend digital components. As technology gets better this will be integrated into contact lenses and glasses for consumers to consume and interact with.
NASA’s take on VR is surprisingly close to the systems we are using today.
NASA worked on the social aspects of vr, creating avatars and enabling communication within the virtual space. This is unsurprising as they were looking at the effect a VR system would have upon long-distance space travel. Whilst NASA concluded that these systems would be beneficial they stopped working on them due to their ability to cause nausea due to low refresh rates and technological ability at the time.
AR has always found a home in more industrial or businesslike settings with 1992 marking the birth of the term “augmented reality.” It first appeared in the work of Caudell and Mizell  at Boeing, who sought to assist workers in an airplane factory by displaying wire bundle assembly schematics in a see-through HMD.
Its engineers were trying to work with wire bundling and cable management around aircraft and would previously have to remember whole constructs such as this one shown below:
From the start, they knew they were onto something when a software engineer was now able to carry out the bundling and management with an early head-mounted, see-through device:
In 1993 a system called KARMA had been created, a system that incorporated knowledge-based AR. This system was capable of automatically inferring appropriate instruction sequences for repair and maintenance procedures. KARMA was the first knowledge-driven AR application. A user with an HMD could see instructions on printer maintenance:
What a customer would see:
What a repair technician would see:
From here, it is easy to see how we got to systems such as hololens and others that keep one rooted in the real world whilst being able to access virtual and simulated data.
Mixed reality (MR), also sometimes referred to as hybrid reality, is the merging of real and virtual worlds combining elements of both AR and VR to produce new environments and visualizations where physical and digital objects co-exist and interact in real time.
Mixed reality aims to keep one immersed in an environment where a prime focus is to keep you in a separate realm, so to speak, distinct from either the real world (where AR keeps you) or an or a virtual realm attempting to replicate the real in a simulation (as in VR). Mixed reality systems have only become available (and in any way useful) as AR and VR have hit maturation as its only with fully realized systemic kinks worked through that the technology industries and back garden shed type hardware hackers can get to the ‘usefulness’ of MR.
Finally, XR is a different animal once more! XR, or, Crossed Reality is when elements of the digital realm are injected back into the real world, crucially, _no extra viewing equipment is required at all by the content consumer_ it is a ‘passive’ experience. So, holographic displays are an example of cross-reality systems, as are volumetric displays. These are systems where one can be stood in a room and walk around and inspect a virtual, simulated thing from multiple angles and distances and not have to do _anything_ that someone wouldn’t have to do if the object was actually physically there.
For example, in the immersive media I enjoy creating, I make use of holographic display technology that i built to highlight/annotate or play with my surroundings such as these examples at Canary Wharf and on the Millenium Bridge in London looking towards St. Paul’s Cathedral:
This article is written by Dimona Dougherty. You can see more of Dimona’s immersive artwork and quick edits utilizing each of these technologies on veer @: https://veer.tv/vr/dimonauk/home