Virtual reality

Virtual reality (VR) is a technology which allows a user to interact with a computer-simulated environment, be it a real or imagined one. Most current virtual reality environments are primarily visual experiences, displayed either on a computer screen or through special or stereoscopic displays, but some simulations include additional sensory information, such as sound through speakers or headphones. Some advanced, haptic systems now include tactile information, generally known as force feedback, in medical and gaming applications. Users can interact with a virtual environment or a virtual artifact (VA) either through the use of standard input devices such as a keyboard and mouse, or through multimodal devices such as a wired glove, the Polhemus boom arm, and omnidirectional treadmill. The simulated environment can be similar to the real world, for example, simulations for pilot or combat training, or it can differ significantly from reality, as in VR games. In practice, it is currently very difficult to create a high-fidelity virtual reality experience, due largely to technical limitations on processing power, image resolution and communication bandwidth. However, those limitations are expected to eventually be overcome as processor, imaging and data communication technologies become more powerful and cost-effective over time.
Virtual Reality is often used to describe a wide variety of applications, commonly associated with its immersive, highly visual, 3D environments. The development of CAD software, graphics hardware acceleration, head mounted displays, database gloves and miniaturization have helped popularize the notion. In the book The Metaphysics of Virtual Reality, Michael Heim identifies seven different concepts of Virtual Reality: simulation, interaction, artificiality, immersion, telepresence, full-body immersion, and network communication. The definition still has a certain futuristic romanticism attached. People often identify VR with Head Mounted Displays and Data Suits.

Future
It is unclear exactly where the future of virtual reality is heading. In the short run, the graphics displayed in the HMD will soon reach a point of near realism. The audio capabilities will move into a new realm of three dimensional sound. This refers to the addition of sound channels both above and below the individual or a Holophony approach.
Within existing technological limits, sight and sound are the two senses which best lend themselves to high quality simulation. There are however attempts being currently made to simulate smell. The purpose of current research is linked to a project aimed at treating Post Traumatic Stress Disorder (PTSD) in veterans by exposing them to combat simulations, complete with smells. Although it is often seen in the context of entertainment by popular culture, this illustrates the point that the future of VR is very much tied into therapeutic, training, and engineering demands. Given that fact, a full sensory immersion beyond basic tactile feedback, sight, sound, and smell is unlikely to be a goal in the industry. It is worth mentioning that simulating smells, while it can be done very realistically, requires costly research and development to make each odor, and the machine itself is expensive and specialized, using capsules tailor made for it. Thus far basic, and very strong smells such as burning rubber, cordite, gasoline fumes, and so-forth have been made. Not content to serve only its customers' eyes and ears, Japan's NTT Communications, of Tokyo, has just finished testing an Internet-connected odor-delivery system to be used by retailers and restaurants to attract customers. Whether NTT has sniffed out a new commercial opportunity or this attempt to engage our olfactory sense will fail the smell test is too early to judge. But as new trials and applications are tried out and more data gathered, Hamada says he is sure the technology “will take communications to a new level in content richness, compared to today’s communications, which only offers images and sounds.