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🔦 Light & Reflection Playground

Bounce a beam of light off mirrors to hit the target, and see the Law of Reflection in action. Want the full theory first? Read Light: Reflection, Refraction & Colour.

🔦 A beam of light is always trying to travel from the source to the target. Your job is to place mirrors in its path so it bends the right way and actually gets there.

How This Works
  1. Find the source and target. The 🔦 is where the beam starts (fixed, you can't move it). The 🎯 is where you're trying to send it (also fixed).
  2. Tap empty squares to add mirrors. Each tap cycles that square through three states: nothing → a ／ mirror → a ＼ mirror → nothing again. Tap as many times as you need to pick the one you want.
  3. Press "🔦 Fire Beam." A glowing line will animate out from the source, travelling in a straight line until it hits one of your mirrors — then it turns 90° and keeps going, exactly like a real mirror reflecting light.
  4. See what happens:
    • ✅ Beam reaches the 🎯 → it turns green and you're told how many bounces it took. You've solved the level.
    • ❌ Beam runs off the edge of the grid → you'll see a message saying it left the grid. Move or add mirrors and try again.
    • 🔁 Beam bounces forever between mirrors → you'll see a "trapped in a loop" message. Change your mirror layout.
  5. No luck? Tap "Clear Mirrors" to wipe the board and start that level over, or pick a different level from the buttons above the grid.
Tip: a ／ mirror bounces a beam moving right (→) so it starts moving up (↑). A ＼ mirror bounces a beam moving right (→) so it starts moving down (↓). Try placing just one mirror first and firing the beam to see exactly how it behaves before adding more.

Choose a level:

Mirrors placed: 0 Bounces: —
Place a mirror or two, then fire the beam to see where it goes.

Law of Reflection: when light hits a mirror, the angle it arrives at equals the angle it leaves at (angle of incidence = angle of reflection). That's the exact rule this puzzle runs on, simplified to 45° mirrors on a grid.