Lecture 5: Augmented & Virtual Reality

A set of vocabulary flashcards summarising the principal terms, technologies and interaction concepts covered in the Augmented & Virtual Reality lecture.

Virtual Reality (VR)

A fully computer-generated, immersive environment that replaces the real world and lets users look, move and interact inside the simulation.

Augmented Reality (AR)

Technology that superimposes digital content onto the live physical world, in real time, registered in 3-D and interactive.

Mixed Reality (MR)

Umbrella concept for experiences that blend real and virtual elements, covering both AR and Augmented Virtuality.

Reality-Virtuality Continuum

Milgram’s scale running from the real environment through AR and AV to a completely virtual environment.

Augmented Virtuality (AV)

Primarily virtual environments that incorporate live elements from the real world.

Head-Mounted Display (HMD)

Wearable device that positions small screens or optics in front of the eyes to present VR or AR imagery.

Sword of Damocles

Ivan Sutherland’s 1968 tethered HMD prototype, regarded as the first true head-mounted display.

Sensorama

Morton Heilig’s 1950s multi-sensory arcade cabinet that delivered early VR-like experiences with visuals, sound, vibration and scent.

LEEP Optics

Eric Howlett’s wide-angle stereoscopic lens system (≈90°–140° FOV) that influenced modern VR headsets.

CAVE (Cave Automatic Virtual Environment)

Room-sized VR system using stereo projection on 3–6 walls with head tracking to immerse users.

Google Cardboard

Low-cost smartphone viewer introduced in 2014 that popularised consumer VR.

Oculus Rift

Crowd-funded 2012 VR HMD that revived consumer interest; later acquired by Facebook.

VPL Research

First commercial VR company (mid-1980s) that sold HMDs, gloves and software.

KinectFusion

Microsoft algorithm that reconstructs and tracks 3-D environments in real time using depth cameras.

Microsoft HoloLens

Optical see-through AR headset that maps surroundings with KinectFusion-like tracking to anchor holograms.

ARCore

Google’s software platform (2017) for phone-based AR tracking and environmental understanding.

Pokemon GO Effect

2016 mass adoption of mobile AR through Niantic’s game, driving public awareness and downloads (>500 M).

Autonomy (AIP Cube)

Property of VR where users and virtual entities can act independently in response to events.

Interaction (AIP Cube)

Dimension describing the user’s ability to manipulate objects and environment within VR.

Presence (AIP Cube)

Feeling of ‘being there’ in a virtual space, fostered by realistic sensory input.

Interaction Gap (Hand-held AR)

Mismatch between 3-D virtual content and 2-D touchscreen input that complicates object manipulation.

Browsing Techniques (AR)

Simple AR interaction style where users inspect overlaid information mainly by changing viewpoint or tapping 2-D UI elements.

Ray Casting

Selection method that projects a virtual line from camera or pointer to choose 3-D objects via their 2-D screen positions.

SlidAR

Hand-held AR technique that lets users slide the phone to accurately position virtual objects in 3-D space.

HOMER-S

One-handed AR technique combining ray casting for selection with scaled hand movement for 3-D manipulation.

3-D Gestures

Mid-air hand or body motions used to select, move or control virtual elements directly in 3-D.

Midas-Touch Problem

Unintended activation of commands when every gesture is interpreted as input in AR/VR systems.

Transitional Interface

UI that lets users smoothly switch along the Reality-Virtuality Continuum, e.g., from map to AR to full VR.

AR Sandbox

Projective AR installation using depth sensing to overlay real-time topographic visuals onto reshaped sand for education.

Redirected Walking

VR locomotion technique that subtly manipulates visuals or body cues so users walk in circles while perceiving a larger virtual path.

Teleportation (VR Navigation)

Locomotion method where users point to a target location and instantly reappear there to reduce motion sickness.

Handle Bar Metaphor

Bimanual mid-air interaction technique that treats two tracked hands as endpoints of a virtual bar for object manipulation.

Tactile Augmented Reality

AR experiences that enhance or alter the sense of touch on real surfaces or objects.

Tacttoo

Thin, feel-through on-skin device that delivers high-resolution vibrotactile patterns for tactile AR and VR feedback.

Haptic Feedback

Artificial touch sensations (vibration, force, texture, temperature, weight) provided to increase realism in VR/AR.

Simulator Sickness

Discomfort (nausea, dizziness) arising from sensory conflicts in VR, a subset of motion sickness.

Affordance

Perceived action possibilities of an object; in VR, virtual objects suggest uses that may not match physical reality.

Constraint

Limitations that restrict how an object can be used; virtual and real constraints may conflict in VR experiences.