Why do we have two eyes? Each eye sees the world from a slightly different place, and your brain uses the difference to see depth. Test your depth power!
🎈 Balloon levels
This is a game, not an eye test. Only an eye doctor can check how well your eyes work together.
Do you have 3D glasses? Red-green, red-blue and red-cyan glasses all work.
You can change this any time from the menu.
3D GLASSES
Your glasses
Check the 3D
How deep?
Less depth is easier on the eyes. More depth pops out more.
1. Hide the green bar
Put the glasses on and cover the eye behind the green lens, so you look only through the red lens. Slide left until the green bar disappears.
2. Hide the red bar
Now cover the eye behind the red lens, so you look only through the green lens. Slide left until the red bar disappears.
3D mode is just a fun way to play. If your eyes feel tired, take a break or play without glasses.
HOW TO PLAY
Nearest balloon: all the balloons look the same size, so size can't help you! Tap the one that is closest to you.
With 3D glasses, your two eyes see two different pictures, just like in real life, so near balloons pop out of the screen.
Without glasses, hold 👀 Move your head: the view sways side to side. Near things move more than far things, just like when you look out of a car window.
Depth match: slide the pin nearer or farther until it is at the same depth as the ring, then press CHECK.
Try 🙈 Close one eye to feel how much harder it is with one eye.
WHY TWO EYES?
Try this: hold a finger up and look at it with one eye, then the other. It jumps! Your eyes are about 6 cm apart, so each one sees a slightly different picture.
Your brain joins the two pictures into one, and uses the difference to feel how far away things are. This is called stereo vision. It helps you catch a ball, pour a drink and thread a needle.
Try touching two pencil tips together with one eye closed. Tricky! Now with both eyes open.
Your brain has other depth clues too: things far away look smaller, near things cover far things, and when you move your head, near things move more. That is why people with one eye can still judge distance pretty well.
3D glasses give each eye its own picture: the red lens lets one picture through and the other lens the second picture.
Lazy eye (amblyopia): if one eye doesn’t see clearly when a child is young, the brain may learn to ignore it. Eye checks find it early, and glasses, eye drops or an eye patch help the weaker eye catch up. It works best when children are young, so kids should have their eyes checked.