Carautonomy — car parts and warning lights explained
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Windscreens

What is a Head-Up Display Windscreen?

Specially layered glass that displays a sharp, ghost-free projected image for HUD cars.

Wedge interlayeraligns reflectionsHUD projector6767⚠ ghosted image (wrong glass)67MPH↑ 400m✓ correct HUD glassHUD glass uses a wedge interlayer so the projected image stays sharp, not doubled

Simplified animation — not to scale.

In plain English

Cars with a head-up display project information (speed, sat-nav, alerts) onto the windscreen so you can read it without looking down. A HUD windscreen uses a special wedge-shaped interlayer that lines up the reflection from the inner and outer glass into a single clear image.

A simple analogy

"Like cinema 3D glasses — only the right lens lines the two images up into one sharp picture."

How it works

Fit the wrong (non-HUD) glass and the projection looks doubled, ghosted or out of focus. The replacement glass must be the correct HUD spec for that exact model.

Signs of trouble

  • Doubled or ghosted HUD image
  • Numbers and arrows look blurry or smeared
  • HUD appears tilted or in the wrong position
  • HUD fine in dry weather, unreadable when wet
Rough UK cost

£700–£1,600

Parts: £600–£1,400
Labour: £100–£200

Always get a written quote. Prices vary by car, region, and parts brand.

Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.

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