Nerdpit Labs

Notebook / Entry 002

Backlighting the overhead, first pass

Planning a 5 V backlight bus for the overhead panel and what I learned about light bleed.

, 1 min read. Filed under lighting, overhead.

Diagram of four panel sections on a shared 5 V backlight bus
One shared 5 V bus, one dimmer, four panel sections.

Panel backlighting is the moment a pile of printed parts starts to look like a cockpit. It’s also where light leaks show up.

The plan

One 5 V bus runs the length of the overhead, with a single PWM dimmer so the whole panel can be turned down for night flying. Each section gets its own short LED strip behind the legend plate.

Light bleed

Bare PETG glows like a lampshade. Two fixes made the difference:

  1. A coat of black primer on the back of every legend plate.
  2. A 1 mm printed baffle around each LED so light only reaches the legend above it.

Wiring notes and the pinout are in the library.