Science · Interactive demo
Why is the background blurry?
Close the aperture and watch the background sharpen. Follow the light inside the lens to see why each far light lands as a disc.
Created by ExplainerTools.
What you’ll explore
This interactive demo gives you a visual way into science. The key ideas include optics, photography, cameras, aperture.
Continue learning
- Why do propellers look bent on camera? by ExplainerTools
- What makes a photo sharp? by ExplainerTools Originals
- Cameras and Lenses by Bartosz Ciechanowski
- The Plane of Focus by Ryan Sael
- Lights and Shadows by Bartosz Ciechanowski
- How the Rainbow Got Its Colors by Kevin Ngo
See how the world works.
Explore interactive ideas in space, science, math, and more. Try a demo, read an interactive article, watch a short video, and follow what makes you curious.
New Originals
Change one thing and see why.
Three new models, each with a 30-second film. Watch the question, then play with the answer.
Follow your curiosity
A collection of small doors into big ideas.
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Opening the collection…
Make something click.
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