Virtual reality

Virtual reality (VR) is a simulated experience that uses computer technology to create an immersive environment. It employs 3D head-mounted displays and pose tracking to give a user the feeling of being inside a virtual world. This technology allows a person to look around, move, and interact with digital items. VR is a key part of the reality-virtuality continuum. This continuum is a scale that connects the real world to purely digital spaces. It is distinct from augmented reality (AR), which blends digital content with a user's real surroundings.

To create this sense of presence, VR systems use specific mechanical and digital processes. A common method involves a head-mounted display (HMD). This device typically contains two small, high-resolution OLED or LCD monitors. These screens provide separate images to each eye, a process called stereoscopic graphics rendering. This technique creates the illusion of a three-dimensional world. The system also uses positional and rotational real-time head tracking. This allows the computer to follow the user's six degrees of movement.

Beyond just sight, VR can engage many senses to deepen immersion. Many systems incorporate binaural audio to provide realistic sound. Some systems also use haptic technology. Haptic technology provides sensory and force feedback, allowing users to feel digital objects. For physical movement, some setups use an omnidirectional treadmill. This device allows a user to perform locomotive motion in any direction. Other methods include projector-based VR, which uses multiple large screens in a room. This can be used for complex tasks like airplane simulation or robot navigation.

The history of VR involves many different visions of simulated reality. In the 1950s, Morton Heilig envisioned an "Experience Theatre." In 1962, he built the Sensorama, a mechanical device. It engaged sight, sound, smell, and touch through short films. In 1968, Harvard Professor Ivan Sutherland created The Sword of Damocles. This was the first head-mounted display system for immersive simulation. It was so heavy that it had to be suspended from the ceiling. The graphics were simple wire-frame model rooms.

As computing evolved, the field moved toward digital systems. In 1978, MIT created the Aspen Movie Map, a crude virtual tour. By 1985, Scott Fisher helped design the VIEW system for NASA. This installation used the LEEP optical system to create a convincing sense of depth. In the late 1980s, Jaron Lanier popularized the term "virtual reality." His company, VPL Research, developed early hardware like the DataGlove. Mattel even licensed this technology to create the Power Glove in 1989.

The 1990s brought more widespread commercial interest in the technology. In 1991, Virtuality launched the first mass-produced, networked, multiplayer VR entertainment system. These systems could cost up to $73,000 per multi-pod unit. They featured headsets and exoskeleton gloves for immersion. In 1990, researchers created the Cave automatic virtual environment (CAVE). This was a cubic immersive room using a multi-projected environment. It allowed people to see their own bodies in relation to others.

Today, VR has many important applications across different industries. It is widely used for entertainment and video games. However, it is also vital for education and professional training. Medical, safety, and military professionals use it to practice difficult tasks. For example, European Space Agency researchers use VR to train astronauts. They practice extinguishing fires inside a lunar habitat. NASA scientists have even used VR to "drive" Mars rovers from Earth. This helps overcome the substantial delays in communication between planets.