1.3 · AR & VR

Goal: distinguish AR from VR; cite uses and limitations.

Definitions

Term	Definition
AR (Augmented Reality)	Overlays digital content on the real world
VR (Virtual Reality)	Completely replaces the real world with a digital one
MR (Mixed Reality)	Digital content interacts with the real environment

Pure real     <---->     Pure virtual
   ▲                          ▲
   │                          │
   ▼ AR              MR       │
                              │
                              ▼ VR

AR examples

• Pokémon GO — creatures overlaid on phone camera view.
• Snapchat / IG filters — facial masks and effects.
• AR navigation — Google Maps "Live View" arrows.
• IKEA Place — preview furniture in your room.
• AR makeup try-on in cosmetic stores.

VR examples

• Gaming — Oculus Quest, PlayStation VR.
• Training — pilot simulators, surgery simulators.
• Virtual museums and concerts.
• Real-estate viewing without travelling.
• Therapy for phobias and PTSD.

Hardware

Device	Used in
Smartphone with camera	AR
AR glasses (Microsoft HoloLens, Magic Leap, Meta Ray-Ban)	AR / MR
VR headset (Meta Quest, PlayStation VR, Apple Vision Pro)	VR / MR
Haptic gloves, treadmills	Advanced VR

Benefits

• Engagement — immersive experiences.
• Safety — train in dangerous scenarios without risk.
• Cost savings — fewer physical prototypes / venues.
• Accessibility — bring distant places (museums, classrooms) to anyone.

Risks

• Motion sickness with VR.
• Privacy — AR glasses can quietly record bystanders.
• Isolation — heavy VR users may withdraw from real social life.
• Cost — high-end equipment still expensive.

Hong Kong context

• HK Maritime Museum has VR experiences.
• HK polytechnics use VR for nursing training.
• Several local startups develop AR retail solutions.

Exam-style question

Q (4 marks): Distinguish AR and VR. Give one educational application of each.

Sample answer:

• AR overlays digital content on the real world (the user still sees their surroundings); VR replaces the real world entirely with a computer-generated environment using a headset.
• AR in education: anatomy app that overlays a 3D heart onto a textbook page when the camera is pointed at it.
• VR in education: virtual tour of the Great Wall of China for history students who cannot travel there.

Key takeaways

• AR = overlay; VR = replace.
• Many real applications: gaming, training, retail, education.
• Watch for privacy and health side-effects.

Chapter wrap-up

You now know AI/data science, 3D printing, AR/VR — the three families the syllabus highlights.

➡️ Next chapter: 2 · Health & Ethical Issues