Tech WondersPlay

Images, Screens & GamesRaster Graphics

Jaggies

Blurring edge pixels slightly makes diagonal lines look smooth

Zoom into any slanted line on a screen and it turns into a staircase. So why does it look smooth from where you sit?

You'll find out

  • Why straight lines turn into steps
  • How a screen picks the squares to light
  • The trick that melts the steps away

Why it matters

Nearly every letter on your screen uses this trick, and so do the games you play.

About 3 min6 interactive slides · 5 questionsLesson 203 · Zone 23

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