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Beam to Pixel

Every pixel on a CRT screen is visited by a single electron beam. Adjust the scan mode, persistence, and focus to watch a beam methodically trace an image — the same way analog video has worked since 1926.

Raster Scan

The beam sweeps every row, left to right, top to bottom — visiting every pixel whether it is lit or not. The Z-axis (beam intensity) is modulated to turn pixels on or off. All broadcast television used this approach.

Vector Drawing

The beam jumps directly to lit pixels, blanked during repositioning. Efficient for sparse images; limited by how many jumps per frame the deflection circuits can handle. Arcade vector displays like Asteroids used this method.

Phosphor Persistence

The phosphor coating does not extinguish instantly. It decays over milliseconds — creating the characteristic green afterglow. Higher persistence masks flicker but smears fast motion. Different phosphor compounds (P1, P31, P39) had different decay rates.