Virtual reality (VR) is the use of computer technology to create a simulated environment. Unlike traditional user interfaces, VR places the user in an experience. Instead of watching on a screen, the user is immersed in the 3D world and able to interact with it. By simulating as many senses as possible, such as sight, hearing, touch and even smell, the computer becomes the gatekeeper to this artificial world.
Virtual reality and augmented reality are two sides of the same coin. You can think of augmented reality as virtual reality with one foot in the real world: Augmented reality simulates man-made objects in real environments; Virtual reality creates an artificial environment that can be inhabited.
In Augmented Reality, computers use sensors and algorithms to determine the camera's position and orientation. Augmented reality then renders 3D graphics as seen from the camera's point of view, superimposing computer-generated images on the user's view of the real world.
In virtual reality, computers use similar sensors and math. However, instead of locating a real camera in a physical environment, the user's eye position is located in a simulated environment. If the user's head moves, the image responds accordingly. Instead of combining virtual objects with real scenes, VR creates a compelling, interactive world for users.
The lenses in a virtual reality head-mounted display (HMD) can focus on the image produced by the display very close to the user's eyes. The lenses are positioned between the screen and the viewer's eyes to give the illusion that the images are at a comfortable distance. This is achieved through the lens in the VR headset, which helps reduce the minimum distance for clear vision.