Colour passthrough is the headline feature of the Quest 3 and 3S — here's what mixed reality really means.
What is passthrough?
Passthrough uses the headset's outward-facing cameras to show you the real world inside the headset. Older Quests did this in grainy black and white; the Quest 3 and 3S do it in full colour, so you can see your room, your hands, your coffee and your phone without taking the headset off.
Passthrough vs full VR
In full VR you're transported somewhere else entirely. In mixed reality (MR), digital objects are layered on top of your real surroundings. The Quest 3's depth sensor lets apps understand where your walls, floor and furniture are, so virtual objects can sit on your real table or robots can crawl out of your real wall.
What you can do with it
Pin virtual monitors above your desk for work, follow a fitness class while still seeing your room, play board games on your coffee table, or let kids battle aliens that smash through the living room. Because you can see your space, MR is also far more comfortable for longer sessions.
The limits
Passthrough still isn't as crisp as your naked eyes, fine text far away can look soft, and very dark or very bright rooms reduce quality. But it's a genuine leap, and it's the direction the whole industry — including Apple — is heading.