Virtual reality headset

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A Meta Quest 3 virtual reality headset and its controllers Meta Quest 3 display unit.jpg
A Meta Quest 3 virtual reality headset and its controllers

A virtual reality headset (or VR headset) is a head-mounted device that uses 3D near-eye displays and positional tracking to provide a virtual reality environment for the user. VR headsets are widely used with VR video games, but they are also used in other applications, including simulators and trainers. VR headsets typically include a stereoscopic display (providing separate images for each eye), stereo sound, and sensors like accelerometers and gyroscopes for tracking the pose of the user's head to match the orientation of the virtual camera with the user's eye positions in the real world. [1] Augmented reality (AR) headsets are VR headsets that enable the user to see and interact with the outside world. Examples of AR headsets include the Apple Vision Pro and Meta Quest 3.

Contents

VR headsets typically use at least one MEMS IMU for three degrees of freedom (3DOF) motion tracking, and optionally more tracking technology for six degrees of freedom (6DOF) motion tracking. 6DOF devices typically use a sensor fusion algorithm to merge the data from the IMU and any other tracking sources, typically either one or more external sensors, or "inside-out" tracking using outward facing cameras embedded in the headset. The sensor fusion algorithms that are used are often variants of a Kalman filter. VR headsets can support motion controllers, which similarly combine inputs from accelerometers and gyroscopes with the headset's motion tracking system.

Most headsets are reliant on a personal computer to operate. Some "standalone" headsets are based on a mobile operating system and smartphone-like hardware, allowing VR apps to run directly on the device, while also allowing VR applications to be streamed from a PC over a USB or Wi-Fi connection. Virtual reality headsets and viewers have also been designed for smartphones, where the device's screen is viewed through lenses acting as a stereoscope, rather than using dedicated internal displays.

History

VPL Research was a company that made early VR headsets in the 1980s. [2]

The PSVR headset for the PlayStation 4 video game console, released in 2016 Sony-PlayStation-4-PSVR-Headset-Mk1-FL.jpg
The PSVR headset for the PlayStation 4 video game console, released in 2016

The Sega VR was announced in 1991 and seen in early 1993 at the Winter CES. It was never released for consoles, [3] but was utilized for the Sega VR-1 motion simulator arcade attraction in 1994. [4] [5] Another early VR headset, the Forte VFX1, was announced at CES in 1994. The VFX-1 has stereoscopic displays, 3-axis head-tracking, and stereo headphones. [6]

Sony released the Glasstron in 1997, which has an optional positional sensor, allowing the wearer to view the surroundings, with the perspective moving as the user's head moves, giving a deep sense of immersion. These VR headsets gave MechWarrior 2 players a new visual perspective of seeing the battlefield from inside the cockpit of their craft. However, these early headsets failed commercially due to their limited technology, [7] [8] and they were described by John Carmack as like "looking through toilet paper tubes". [9]

In 2012, a crowdfunding campaign began for a VR headset known as Oculus Rift; the project was led by several prominent video game developers, including John Carmack [7] who later became the company's CTO. [10] In March 2014, the project's parent company Oculus VR was acquired by Facebook for $2 billion. [11] The final consumer-oriented release of Oculus Rift began shipping on 28 March 2016. [12]

In March 2014, Sony demonstrated a prototype headset for PlayStation 4, [13] which was later named PlayStation VR. [14] In 2014, Valve demonstrated some headset prototypes, [15] which led to a partnership with HTC to produce the Vive, which focuses on "room-scale" VR environments that users can naturally navigate within and interact with. The headset uses Valve's "SteamVR" software platform. [16] The Vive was released in April 2016 [17] and PlayStation VR in October 2016. [18]

Google released a series of specifications and associated DIY kits for virtual reality viewers known as Google Cardboard; these viewers are capable of being constructed using low-cost materials (and a smartphone with a gyroscope), such as cardboard (hence the naming). Samsung Electronics partnered with Oculus VR to co-develop the Samsung Gear VR (which is only compatible with some Samsung Galaxy devices). LG Electronics developed a headset with dedicated displays for its LG G5 smartphone known as LG 360 VR. [19] [20] [21] [22] In March 2017, Microsoft launched a platform for VR and mixed reality headsets running on Windows 10 known as Windows Mixed Reality, with VR headsets from multiple partners including PC makers Acer, Dell, HP Inc., and Lenovo. [23]

In 2018, Oculus released the Oculus Go, a standalone headset running capable of running VR apps on embedded mobile computing hardware, thus not needing a PC or an inserted smartphone to operate. [24] In June 2019, Valve released their own in-house SteamVR headset, the Valve Index. [25] In an October 2019 report, Sony, Facebook (Oculus), and HTC were identified by Trend Force as the three largest manufacturers of VR hardware. [26] 2019 saw Facebook release the first-generation Oculus Quest, a successor to the Oculus Go concept which supports motion controllers and positional tracking with 6DOF. [27] [28]

Technology

Resolution and display quality

There are different optics and visual qualities that affect how an individual perceives the image quality and how they experience the virtual world. The image clarity depends on the display resolution, optic quality, refresh rate, and field of view. [29]

Because virtual reality headsets stretch a single display across a wide field of view (up to 110° for some devices according to manufacturers), the magnification factor makes flaws in display technology much more apparent. One issue is the so-called screen-door effect, where the gaps between rows and columns of pixels become visible, kind of like looking through a screen door. [30] This was especially noticeable in earlier prototypes and development kits, [8] which had lower resolutions than the retail versions.

Optics

An image displayed by a VR headset, showing compensation for lens distortion and chromatic aberration Sample screen capture of Oculus rift development kit 2 screen buffer.jpg
An image displayed by a VR headset, showing compensation for lens distortion and chromatic aberration

The lenses of the headset are responsible for mapping the up-close display to a wide field of view, [31] [32] while also providing a more comfortable distant point of focus. One challenge with this is providing consistency of focus: because eyes are free to turn within the headset, it is important to avoid having to refocus to prevent eye strain.

Fresnel lenses are commonly used in virtual reality headsets due to their compactness and lightweight structure. [33] [34] The lenses do not use multiple pieces of material in their lenses like other lenses, but the lens will be broken down into sections, allowing the individual to have a wider range of view. The issue seen with the lens consists of seeing the ridges of the lenses when the headset is not properly aligned on the head. [29] [34]

The lenses introduce distortion and chromatic aberration, which are typically corrected in software. [31] [34] The lenses can also be adjusted dynamically to account for a user's eyeglass prescription so that the user can use the headset without corrective eyeglasses. [35]

Latency requirements

Virtual reality headsets have significantly higher requirements for latency the time it takes from a change in input to have a visual effectthan ordinary video games. [36] If the system is too sluggish to react to head movement, then it can cause the user to experience virtual reality sickness, a kind of motion sickness. [37] According to a Valve engineer, the ideal latency would be 7-15 milliseconds. [38]

The graphics processing unit (GPU) also needs to be powerful enough to render the required amount of frames. Oculus cited the limited processing power of Xbox One and PlayStation 4 as the reason why they targeted the PC gaming market with their first devices. [39]

Foveated rendering is a new technique to reduce the rendering workload. It uses eye tracking hardware to determine at what point the user is looking and reduces rendering resolution farther from the user's gaze. This can be unnoticeable to the user because human peripheral vision is far less sensitive than the fovea. [40]

Uses in various fields

A U.S. soldier being prepared to use a ground combat training virtual reality headset at Fort Stewart in 2013 Virtual reality training 130416-A-BZ540-008.jpg
A U.S. soldier being prepared to use a ground combat training virtual reality headset at Fort Stewart in 2013

Medical training and diagnostics

Virtual reality headsets are being currently used as a means to train medical students for surgery. It allows them to perform essential procedures in a virtual, controlled environment. Students perform surgeries on virtual patients, which allows them to acquire the skills needed to perform surgeries on real patients.[ citation needed ] It also allows the students to revisit the surgeries from the perspective of the lead surgeon. [41]

Traditionally, students had to participate in surgeries and often they would miss essential parts. Now, with the use of VR headsets, students can watch surgical procedures from the perspective of the lead surgeon without missing essential parts. Students can also pause, rewind, and fast-forward surgeries. They also can perfect their techniques in a real headset, mounted in a risk-free environment. [42]

Besides training purposes, augmented reality headsets are also already being used for image-guided surgery.[ citation needed ]

VR headset mounted smartphones have been used to capture high-quality videos and images of the retina for documenting peripheral retinal lesions. [43]

Military training

Virtual reality headsets have been used by the United States Armed Forces. It is a particularly useful tool for training military personnel without putting them in harm's way. [44]

The virtual reality headset allows military personnel to interact with virtual reality people to make it feel real. They can talk to one another and do varying actions to make the virtual reality world feel like they are actually in the real world. There are also disadvantages and advantages when military personnel use the headset. The disadvantage is the headset is made for an indoor area, with a cool environment, and away from any heat, so when military personnel has just the headset on, no military equipment, it is not like their basic training. The advantages consist of repeating the situations multiple times and the cost of having the headset is less, due to no military equipment being needed. [45]

See also

Related Research Articles

<span class="mw-page-title-main">Virtual reality</span> Computer-simulated experience

Virtual reality (VR) is a simulated experience that employs 3D near-eye displays and pose tracking to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment, education and business. VR is one of the key technologies in the reality-virtuality continuum. As such, it is different from other digital visualization solutions, such as augmented virtuality and augmented reality.

<span class="mw-page-title-main">360-degree video</span> Visual arts technique

360-degree videos, also known as surround video, or immersive videos or spherical videos, are video recordings where a view in every direction is recorded at the same time, shot using an omnidirectional camera or a collection of cameras. The term 360x180 can be used to indicate 360° of azimuth and 180° from nadir to zenith. During playback on normal flat display the viewer has control of the viewing direction like a panorama. It can also be played on a display or projectors arranged in a sphere or some part of a sphere.

<span class="mw-page-title-main">Motion controller</span> Video game controller that tracks motions

In computing, a motion controller is a type of input device that uses accelerometers, gyroscopes, cameras, or other sensors to track motion.

<span class="mw-page-title-main">Oculus Rift</span> Virtual reality headsets by Oculus VR

Oculus Rift is a discontinued line of virtual reality headsets developed and manufactured by Oculus VR, a virtual reality company founded by Palmer Luckey that is widely credited with reviving the virtual reality industry. It was the first virtual reality headset to provide a realistic experience at an accessible price, utilizing novel technology to increase quality and reduce cost by orders of magnitude compared to earlier systems. The first headset in the line was the Oculus Rift DK1, released on March 28, 2013. The last was the Oculus Rift S, discontinued in April 2021.

<span class="mw-page-title-main">Reality Labs</span> Virtual and augmented reality products company

Reality Labs, formerly Oculus VR, is a business and research unit of Meta Platforms that produces virtual reality (VR) and augmented reality (AR) hardware and software, including virtual reality headsets such as the Quest, and online platforms such as Horizon Worlds. In June 2022, several artificial intelligence (AI) initiatives that were previously a part of Meta AI were transitioned to Reality Labs. This also includes Meta's fundamental AI Research laboratory FAIR which is now part of the Reality Labs - Research (RLR) division.

<span class="mw-page-title-main">Google Cardboard</span> Discontinued virtual reality platform

Google Cardboard is a discontinued virtual reality (VR) platform developed by Google. Named for its fold-out cardboard viewer into which a smartphone is inserted, the platform was intended as a low-cost system to encourage interest and development in VR applications. Users can either build their own viewer from simple, low-cost components using specifications published by Google, or purchase a pre-manufactured one. To use the platform, users run Cardboard-compatible mobile apps on their phone, place it into the back of the viewer, and view content through the lenses.

<span class="mw-page-title-main">Samsung Gear VR</span> Virtual reality headset by Samsung

The Samsung Gear VR is a virtual reality headset developed by Samsung Electronics, in collaboration with Oculus VR, and manufactured by Samsung. The headset was released on August 21, 2015.

<span class="mw-page-title-main">Windows Mixed Reality</span> Mixed reality platform

Windows Mixed Reality (WMR) is a discontinued platform by Microsoft which provides augmented reality and virtual reality experiences with compatible head-mounted displays.

<span class="mw-page-title-main">HTC Vive</span> Virtual reality headset

HTC Vive is a line of virtual and mixed reality headsets produced by HTC Corporation. The brand currently encompasses headsets designed for use with personal computers as well as standalone headsets such as the Vive Focus line, Vive Flow glasses, and the Vive Elite XR mixed reality headset.

Virtual Desktop is remote control software for Android-based virtual reality headsets. It allows users to control a PC over a wireless LAN from the headset, including the ability to stream VR games and software.

<span class="mw-page-title-main">Google Daydream</span> Discontinued virtual reality platform by Google

Daydream is a discontinued virtual reality (VR) platform which was developed by Google, primarily for use with a headset into which a smartphone is inserted. It is available for select phones running the Android mobile operating system that meet the platform's software and hardware requirements. Daydream was announced at the Google I/O developer conference in May 2016, and the first headset, the Daydream View, was released on November 10, 2016. To use the platform, users place their phone into the back of a headset, run Daydream-compatible mobile apps, and view content through the viewer's lenses.

<span class="mw-page-title-main">Virtual reality game</span> Video game played in virtual reality

A virtual reality game or VR game is a video game played on virtual reality (VR) hardware. Most VR games are based on player immersion, typically through a head-mounted display unit or headset with stereoscopic displays and one or more controllers.

<span class="mw-page-title-main">Oculus Go</span> Untethered virtual reality headset by Oculus VR

The Oculus Go is a discontinued, standalone virtual reality headset developed by Meta Reality Labs in partnership with Qualcomm and Xiaomi. It is in the first generation of Facebook Technologies' virtual reality headsets, and the company's first device in the category of standalone VR headsets, which was a new category at the time of the Go's release. The Oculus Go was unveiled on October 11, 2017 during the Oculus Connect developer conference, and released on May 1, 2018. Xiaomi launched their own version of the headset in China as the Mi VR Standalone on May 31, 2018.

<span class="mw-page-title-main">Oculus Quest</span> Virtual reality headset

The first-generation Oculus Quest is a discontinued virtual reality headset developed by Oculus, a brand of Facebook Inc., and released on May 21, 2019. Similar to its predecessor, Oculus Go, it is a standalone device, that can run games and software wirelessly under an Android-based operating system. It supports positional tracking with six degrees of freedom, using internal sensors and an array of cameras in the front of the headset rather than external sensors. The cameras are also used as part of the safety feature "Passthrough", which shows a view from the cameras when the user exits their designated boundary area known as "Guardian". A later software update added "Oculus Link", a feature that allows the Quest to be connected to a computer via USB, enabling use with Oculus Rift-compatible software and games.

<span class="mw-page-title-main">Oculus Rift CV1</span> Virtual reality headset by Oculus VR

Oculus Rift CV1, also known simply as Oculus Rift, is a virtual reality headset developed by Oculus VR, a subsidiary of Meta Platforms, known at the time as Facebook Inc. It was announced in January 2016, and released in March the same year. The device constituted the first commercial release in the Oculus Rift lineup.

<span class="mw-page-title-main">Quest 2</span> Virtual reality headset

Quest 2 is a standalone virtual reality headset developed by Reality Labs, a division of Meta Platforms. It was unveiled on September 16, 2020, and released on October 13, 2020 as the Oculus Quest 2. It was then rebranded as the Meta Quest 2 in 2022, as part of a company-wide phase-out of the Oculus brand following the rebranding of Facebook, Inc. as Meta.

<span class="mw-page-title-main">Vergence-accommodation conflict</span> Visual and perceptual phenomenon

Vergence-accommodation conflict (VAC), also known as accommodation-vergence conflict, is a visual phenomenon that occurs when the brain receives mismatching cues between vergence and accommodation of the eye. This commonly occurs in virtual reality devices, augmented reality devices, 3D movies, and other types of stereoscopic displays and autostereoscopic displays. The effect can be unpleasant and cause eye strain.

<span class="mw-page-title-main">Meta Quest Pro</span> Virtual reality headset

The Meta Quest Pro is a mixed reality (MR) headset developed by Reality Labs, a division of Meta Platforms.

Meta Horizon OS, previously known informally as Meta Quest Platform or Meta Quest OS, is an extended reality operating system for the Meta Quest line of devices released by Meta Platforms. Initially developed for the embedded operating system on the Oculus Rift and Oculus Rift S, the platform has been based on the Android operating system since the release of the Oculus Go in 2018. It first supported augmented reality via grayscale camera passthrough upon the release of the Oculus Quest in 2019, and has supported color passthrough since the release of the Meta Quest Pro in 2022.

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