Virtual Reality Devices

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Several models of virtual reality devices as of 2015

List of virtual reality devices:

Virtual reality (VR) devices are a type of wearable devices that are worn on the head and display information directly into the user's eyes through one or more electronic displays present in the device. Together with smart glasses and smart contact lenses, they create the head mounted displays category. The virtual reality feeling is achieved by splitting the image, or using two displays, of the displayed information in such a way that a stereoscopic view is created. This creates the feeling of depth in what the user sees and strengthens the immersion of the virtual reality. Additionally, other means of increasing the immersion are often present. These can include sensors to register the position and tilt of the device, which can then be carried over to the virtual reality, headphones to play sound and/or music, or eye- and hands-tracking technologies.

Unlike smart glasses, virtual reality devices are fully enclosed and, with the exception of some hybrid devices, they are not see-through and thus do not combine the actual and virtual realities together. The reality is not altered, but it is completely blocked out instead.

Historical overview

The first experiments with devices that we could call virtual reality devices began in the first half of the 20th century. American film-maker and inventor Morton L. Heilig, in pursuing his goal of constructing an ultimate-experience theatre, constructed a multimedia device that he called the Sensorama.[1] It was a mechanical device capable of displaying a stereoscopic 3D image, playing stereo sound, and tilting the user sitting in front of it depending on what was happening on the screen. It was also equipped with an aroma dispenser to convey smells of the environment being displayed. Unfortunately, Heilig did not manage to secure funding for his project and the Sensorama remained a prototype only.

The Sword of Damocles device with its mechanical head tracking sensors in place.

While certainly a device capable of virtual reality, the Sensorama was purely mechanical in nature. A true virtual-reality machine, one that displays a computer-generated environment, was called The Sword of Damocles.[2] The name was fitting, because the device was quite bulky and had to be attached to a mechanical arm on the ceiling. It was constructed by computer scientist and computer graphics pioneer Ivan E. Sutherland and his student Bob Sproull in 1968. At that time, they both worked at the Massachusetts Institute of Technology (MIT), and their experiments with a head mounted display are believed to be the first of their kind. The displayed graphics comprised simple wire-frame rooms and offered mechanical head tracking.

In July 1963, Hugo Gernsback invented the first wearable virtual reality display. The glasses served as a small television, while each eye had its separate screen. Therefore, it delivered stereoscopic images as 3D glasses. He called his invention 'teleyeglasses'.[3]

Hugo Gernsback wearing his teleyeglasses

MIT continued leading the VR research and in 1977 introduced multimedia system Aspen Movie Map funded by the Advanced Research Projects Agency (ARPA). Essentially an interactive video recorded with four car-mounted cameras, the resulting virtual environment of the city of Aspen in Colorado could be navigated in a way similar to Google Street View today. The user could choose an arbitrary path through the virtual city, and because Aspen was filmed twice, in early fall and winter, the viewer was able to change the season on demand.

The term 'virtual reality' become widespread starting in the 1980s with the computer scientist Jaron Zepel Lanier Lanierthe and the creation of the VPL Research, company which was among the first to develop and also sell virtual reality products. Among the products, the most notable are the Data Glove, a gestural interface device worn on one's hand that would translate the movements of the hand and individual fingers into the virtual environment. The company's second notable product was the EyePhone, a head mounted display capable of head-tracking.

In 1990 and onward, virtual reality advanced faster together with computer technology. The previously expensive and complicated technical solutions became cheaper and more feasible due to the evolution in computer graphics and performance. VR was no longer confined to military or enterprise applications, but began expanding into the entertainment industry as well. In 1991, Sega Holdings announced Sega VR, a rather unsuccessful head-tracking VR device for arcades. Sega cancelled the development of the home version and discontinued the arcade models, saying that the virtual reality was too real and that users could injure themselves. Due to the graphical limitations, this was highly unlikely, and the real reason for the withdrawal was most likely the possibility of headaches and motion sickness induced in users.[4] A similar device, the Virtual Boy by Nintendo, entered the market in 1995. It was marketed as the first portable video console capable of virtual reality. Nintendo anticipated a great demand for the devices, but Virtual Boy was a failure. The marketing campaign was poorly handled, and reviews criticised the discomfort that the device caused (bad ergonomics, headaches, motion sickness) and wondered about its longevity. The device lacked any head-tracking features, which resulted in poor immersion and only a passive 3D experience. The device did not sell very well and was quietly discontinued in 1996.

The development of VR continued, but only within enterprise applications. In 2014, Palmer Luckey introduced the Oculus Rift VR headset. The entrance of Oculus Rift, and other devices that followed, marked a new era in the evolution of virtual reality. The now affordable hardware allows for great performance and thus immersion, while the resulting device is still inexpensive enough that a general consumer can afford to buy it. Seeing the success of Oculus, other companies quickly followed with their own solutions.

At Consumer Electronics Show (CES) in January 2016, Oculus and HTC unveiled consumer-ready versions of their VR headsets Oculus Rift and HTC Vive, and both companies also announced their release dates. The same month, Google's parent corporation Alphabet established a virtual reality computing division.[5]

Summary of technical aspects

A virtual reality device is a type of a head mounted display that is fully enclosed and only displays a computer-generated image. This is achieved by a LED display or similar technology. The device is able to display stereoscopic images and thus achieving the illusion of depth. This is managed by using either two separate displays, one for each eye, or by splitting the image in two. Because of this, the image has to be essentially generated twice. With the additional need for high resolution, this is a significant performance requirement and also the reason that affordable consumer applications were not available until 2015.

The display is combined with optics that help the eyes to focus on a display that is very close and would otherwise be blurry when looked at from such a short distance. Optical techniques also help with the narrow field of view, which has to be considerably large to not cause discomfort to the user (humans have a field of view up to 180 degrees) and to enhance the immersion factor.

With the exception of smartphone holders, VR devices have to be connected to a computer, because the hardware required to create a VR image of suitable quality is still too bulky to fit into a head-mounted unit. The device is connected to the computer either via cabling or wirelessly.

Other features include some form of gaze and position tracking. Some headsets also feature headphones.



The 'gamification' of the education process is already taking place in the form of computers being introduced into schools. This can be further expanded with the introduction of VR devices, which could act as a potent way to familiarize students with topic more intimately and interactively. For example, the teacher and the students could undertake a virtual voyage inside the human body during a biology class, or they could travel through time during a history class. In these and similar instances, the immersion that VR devices produce could help students to better remember the material they are being taught. These applications are still in an experimental stage, but we may see a rise in VR being used in schools with more affordable devices coming to the market.[6]


Similarly, VR devices can be used to train professionals, much like pilots already use a simulated environment to learn how to control an airplane. Virtual reality can be employed in any situation where the real-world training would be too risky or expensive. A simulated environment offers both total control and shorter time between training sessions. These advantages allow VR to be successfully deployed in the military[7], to train doctors in complicated surgeries[8], or to train fire engine drivers[9].

Enhancement or treatment

As mentioned in the Use section, virtual reality has great potential for therapeutic applications. VR may allow physicians and researchers precise control of the 3D stimulus and give them the ability to completely record patients' behaviour. Virtual reality devices can be used not only in the assessment phase of a psychological examination, but also during rehabilitation. Thanks to their great immersive factor, they can provide naturalistic settings and combine restorative and functional approaches together while eliminating their weaknesses. The restorative approach relies heavily on memorisation and attention; it trains the patient how to think, whereas the functional approach tries to engage the patient in an activity and teach the patient how to do. These two approaches can be effectively combined into one using virtual reality. This will also eliminate the dull memorisation aspect of the restorative approach and the rigidity and artificiality of the functional approach.[10]

Another case in which virtual reality could be very beneficial is pain management. Immersive virtual environments can be a good distraction for a patient undergoing painful medical procedures. These benefits already have been demonstrated experimentally.[11]


William Ford, USC Institute for Creative Technologies' first virtual human and one of the personas of the SimCoach project

Applications in therapy closely resemble those in the medical field. But as opposed to training doctors for their duties, virtual therapy is aimed at patients. Virtual reality can enhance the traditional interviews that happen in the assessment phase of therapy, to help patients with anxiety to actually undertake the interview. Instead of a real therapist, the patient can talk to a virtual avatar in a controlled and comfortable virtual environment, which could also be done from the patient's home. This may be the way for hesitant patients to overcome their resistance to seek care.[12]

The ability to absolutely control the virtual environment, thus giving therapists an affordable and effective way to create scenarios tailored to individual patients, is used in subsequent therapy as well. Applications already exist to treat veterans suffering from PTSD[12], various phobias[13], or to rehabilitate sex offenders,[14] strengthen stress resilience in patients with anxiety, or to help those who suffered from traumatic brain injuries to regain their cognitive functions.


Entertainment is perhaps the biggest potential field for virtual reality applications. But it is only now, when these devices are becoming affordable enough to be deployed in the consumer sector, that we will see a rise in entertainment applications. The new generation of VR headset, which began with the success of Oculus Rift, is already being experimented with by video game developers. Some developer studios are focused solely on VR.[15]

Other applications

Virtual reality can be used in a number of other applications. Urban planners may want to use VR to showcase their work, offering virtual tours through buildings and cities that exist only as plans.[16] Archaeologists could use virtual reality to show how an archaeological site looked in the past. Finally, artists could find a whole new dimension to express themselves in virtual reality. Other forms of artistic or scientific visualisations are also very likely to be used.

A scene from Waves of Grace, a short film by, showing the life in Ebola -stricken Liberia

Virtual reality can be a tremendous tool for those who wish to aim at a user's empathy. It is already used by nonprofit organisations for their promotions. For example, the Clinton Global Initiative[17] released a VR video starring former U.S. President Bill Clinton about its work in East Africa.[18] The immense effect that virtual reality can have on human empathy is utilized by other institutions also. The United Nations created several short VR stories such as the film Waves of Grace, about Liberia recovering from the Ebola epidemic.[19] Data on charitable giving show donations by one in six people who watched such films, which is double the usual rate.[20] These can be used to greatly influence the opinions and decision of those who may otherwise not be able to get the first-hand experience of these often remote events.[21][22] The Virtual Human Interaction Lab at Stanford University is researching the effect that virtual reality can have on empathy and how it can change a viewer's opinion on environmental, societal, or economical issues.

The enhancement that VR provides could also be used for improvement of animal's lives. A company called 'Second Livestock' has suggested that VR devices could deliver virtual reality to chickens and let the feel them are in a free range.[23]

Relevant issues


The immersive virtual environment may become almost indistinguishable from reality. This is beneficial if virtual reality is used for training purposes, because the experience during the training will be so close to a real experience. Soldiers may train during virtual combat without actually having their lives in danger. But immersive combat scenarios, similarly to real combat, may lead to desensitisation. Soldiers experiencing particularly visceral virtual training will be less affected by violence. While this may be desirable for military purposes, the goal of the training is to make the soldiers resilient to violent situations, and the same may happen to non-military users as well. Truly immersive and lifelike combat training simulations probably would not be available to civilians, but virtual reality games that come close to these simulations could be immersive enough to have such effects.

This negative effect applies to empathy-influencing films. As Samantha Storr,[24] the executive producer at, points out, viewers who are immersed in VR are in comparison to traditional TV viewers more vulnerable to positive as well as negative influences. Those who would wish to force their agendas now have an effective tool to do so.[22]

Violence in VR

Virtual reality provides an immersive experience, which could be harmful in the case when violence appears in it. The violence in video games and the moral responsibility of their creators have been intensively discussed in recent years.[25] It is deemed that VR, which makes experiences more intense and which could even mediate an embodiment with a VR avatar, could increase the negative impact of the violence.[26] There is, however, no conclusive claim, as to whether the violence in video games affects human behaviour. Certain studies have even suggested that it could lessen the violence in society.[27]


The advantages of virtual reality are that it will be able to faithfully simulate anything and make the simulation believable. This shortens the gap between what is virtual and what is real, and users may decide that the controlled and likeable simulation they are experiencing in virtual reality is more attractive than actual reality. They will want to spend more time inside the virtual reality, becoming addicted to it. They will seek out any means to either be inside the simulated reality or to get the means to do so, maybe even turning to criminal acts. This will have adverse effects on their own real life as well as on the lives of others.

Avoiding human-human interaction

This issue goes hand in hand with the one mentioned above. The great immersive factor of virtual reality, especially when advanced and inclusive of more natural methods of input, e.g., voice commands, gestures, and gaze, may eventually lead to bonding between the user and the virtual environment and virtual, non-human avatars inside the environment. Bonding by itself is not a problem—this is the reason that virtual environments and by extension virtual reality become more popular—but problems arise when a user is so involved in the environment and the avatars, that he or she would rather spend time with the avatars than with humans, probably even avoiding real human interaction altogether. The advancements in perceptual user interfaces[28] and relevant technologies, such as artificial intelligence, computer graphics, binaural audio, haptic feedback, etc. will only deepen the bond some users may develop with virtual environments.

Of course, several questions arise. Is it feasible to talk about avoiding human interaction at all? Surely there are examples of avoiding social interaction due to the abuse of the virtual; the Japanese phenomenon of hikikomori is one such example. But on the other hand, there are online communities that are very involved but their users don't neglect their real-life interactions and function. A similar point can be raised with regard to the television. While it certainly created so-called 'couch-potatoes', it did not make viewers to adopt this lifestyle en masse. That is not to say that Internet or TV or any other addiction is not a genuine problem, but we cannot say with certainty that interactions inside a sufficiently advanced environment will result in the majority of people totally neglecting their real lives.

Health risks


Virtual reality may have the ability to be almost totally faithful in the future, but the current state of the technology, while still having an advanced immersion factor, still doesn't completely detach the user from actual reality. This conflict between perceptions and senses causes negative effects such as eyestrain, headache, pallor, sweating, dryness of mouth, nausea, motion sickness, vertigo, disorientation, and ataxia, together known under the term cybersickness.[29][30] These effects can be mitigated by using more advanced virtual reality technology as well as by performing virtual tasks that do not differ significantly from what the user is doing in actual reality, e.g., the user is playing a virtual simulation of piloting a spaceship while sitting in his real chair; in this way the disconnection between realities is smaller and cybersickness will not be as severe.


Aftereffects describes the symptoms that occur after leaving the virtual reality. These could include disturbed locomotion, flashbacks, postural control and perceptual disturbances, and fatigue. These are hypothesised to be the results of the user adapting to different sensorimotor requirements of the virtual reality, and upon leaving it, the user has to re-adapt to the real world. These effects can be reduced by gradual exposure to the virtual reality.

Tetris syndrome

The symptoms of aftereffects are perhaps similar to those of Tetris syndrome. Tetris syndrome occurs when users, in this case most likely a avid players, perform a particular activity, i.e., playing a video game or spending such a large amount of time inside a virtual environment that they start to see patterns from the game or virtual reality in their thoughts, dreams, and when they close their eyes.[31]

Public and media impact

The media and subsequently the public impact of virtual reality devices is closely connected to its convoluted history. After attention to VR declined in the middle of the 1990s, the media shifted its focus to other things. It was in 2012–2013, when Oculus founder Palmer Luckey introduced his prototype of Oculus Rift and successfully funded its development through Kickstarter, that the media focused again on virtual reality technology. Facebook' purchase of Oculus[32] made even more clear that virtual reality devices are something the media should focus on in the upcoming years. Financial analyses predict that the virtual reality industry, especially the mobile sector, will be worth about $4.5 to $7 billion worldwide by the year 2020, and it will still continue to rise after that.[33][34]

The success of Oculus Rift has inspired numerous large and small companies and startups to develop their own virtual reality device, or at least develop relevant technologies or VR applications. The year 2015 was a year of great enthusiasm for virtual reality. Some even went so far as to call it the VR renaissance.[35] The attention was not limited to video games, the media also devoted time to report on professional applications of VR, such as ongoing research into possible educational,[36] medical,[37] or military[38] applications.

Of course, the interest in virtual reality did not escape the areas of popular culture and even politics. Many popular figures and celebrities tried to produce content for virtual reality. Popular television host Conan O'Brien has made some of his shows available for virtual reality devices.[39] Disney animator Glen Keane, who created characters like Alladin, appeared in a video showcasing the HTC Vive.[40] VR users can hang out with their favourite celebrities with My360, a Samsung Gear VR series[41] of free 3D videos available for virtual headsets and smartphones.[42] VR also made an appearance in the U.S. 2016 presidential election campaigns.[43] CNN and NextVR made the first democratic presidential debate in the U.S. available to Samsung Gear VR users as well as a regular TV audience. Wired reported that the experience was almost as if one were sitting in the actual audience, albeit they complained that everything looked too 'glossy and fake' and that the VR experience was the only thing a viewer could do with his or her phone or surroundings without taking the VR device off.[44]

Public policy

We have not recorded any public policy that focuses on virtual reality or virtual reality devices.

Related Technologies, Projects, or Scientific Research

Leap Motion has developed a technology that is supposed to track hands. They do not intend to build their own virtual reality devices, but they have offered their technology to other developers of VR headsets. The manufacturers claim that they would announce their product in the beginning of the year 2017.[45]

CamSoda introduced a smelling mask, which could be added to a VR headset and allow users to encounter different smells in virtual reality.[46]

The researchers from Hasso Plattner Institute in Potsdam are developing a device, which allows to feel the objects in VR as to be real.[47]

Reliefband Neurowave introduced at CES 2017 a handband that is supposed to reduce cybersickness. Its results have been proved clinically.[48]

The manufacturers of BrainStation suggest that their device could be used in VR.[49]


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