The Basics of Virtual Reality Technology

What do you think of when you hear the words virtual reality? Does it conjure images of Keanu Reeves stopping a hail of bullets in The Matrix? Or do you picture someone wearing a virtual reality (VR) headset exploring digitized real-life environments or imagined worlds?

Often when people think of virtual reality they think of the end results, the experience. There are, however, many important pieces of technology that help create an immersive experience, including sophisticated software and hardware.

Below is a primer on virtual reality technology.

The Software

Creating a virtual reality experience starts with the software. VR programs create telepresence—a simultaneous sense of immersion and interactivity with a virtual environment. Computer scientist Jonathan Steuer describes two components needed to achieve this—depth of information, and breadth of information.

Depth of information refers to the quality of data being transmitted to the user—-latency (the delay between user action and the resulting action in the virtual world), audio quality, the environment’s level of detail, etc.

Breadth of information is defined as the simultaneous presentation of sensory input. Essentially, providing multiple methods of sensory stimulation to the user at once creates a more complete feeling of immersion.

This feedback is primarily visual and auditory, but some systems also provide tactile feedback through data gloves. Simulations like Disney’s Soarin’ Over California even waft the scent of orange tree groves for the user.

That sensory feedback is processed through some or all of the following virtual reality technology.

The Headset

The virtual reality headset is the primary mode of user interaction with the virtual environment. Headsets like Oculus VR’s forthcoming Rift use OLED panels for each eye, each with a refresh rate of 90hz and low persistence (an image is only displayed for two milliseconds per frame). The combination of low persistence and refresh rate work to eliminate motion blur, enhancing immersion.

Many headsets include integrated headphones that transmit spatialized, binaural audio. The hardware also must perform a head tracking function; the Rift does this through an external infrared camera called “Constellation,” which tracks infrared LEDs on the headset’s surface. Most VR headsets currently in development (like Sony’s Morpheus prototype) feature 1080p resolution per eye, a 90-degree field of view, and head tracking sampling rates up to 1000hz.

Input Devices

The other key component to a VR system is the input device—the method by which the user interacts with the environment.

Users interact through either a gamepad (the Rift is paired with an Xbox One wireless controller), or a motion control device. Devices like data gloves track finger motion, with some being able to provide haptic feedback, recreating a sense of touch through pressure, texture, vibration, etc.

A blend of the two, Oculus plans to release a pair of controllers called Oculus Touch. The Touch is a set of handheld motion controllers that use buttons like a gamepad, but are also tracked in 3D space and appear to the user in the environment.

Other systems allow the user to literally walk through the environment, through the use of a multidirectional platform. Others even place the user in a real-world, room-sized cube (a cave automatic virtual environment, or CAVE), where the environment is projected on each wall, and the user’s motions are tracked by cameras and sensors.

Future Developments

Virtual reality’s arrival for the mainstream consumer is almost here—the Oculus Rift is scheduled for wide release in 2016, and a number of competitors are burning the midnight oil to get their products to market—Sony, HTC, and others are all putting final touches on their own VR systems.

As processing power increases and high resolution displays get better and better, it’s hard to tell what applications the industry will dream up. One thing is certain, however—our reality is changing.