A light cover protects the light engine and defines what the fixture looks like. In most designs it also does the optical work, so the two roles have to be specified together.
Decide what the cover is for
Some covers are purely protective — a clear shield over a separately lensed engine. Most do both: they protect and they diffuse. Saying which role dominates prevents over-specifying optics or under-specifying protection.
Match the geometry to the housing
Snap-in, clip-on, lay-in and wrap-around details are all extruded. The fixing detail is part of the die, so it should be settled before tooling rather than adjusted afterwards.
Material and finish
Polycarbonate for impact and temperature; PMMA for clarity and UV stability. Clear, opal, frosted, embossed and prismatic finishes are all available, and opaque trims can be co-extruded into the same profile.
Specify the appearance when the light is off
Many fixtures are judged switched off. Colour, gloss level and how much of the interior is visible are worth stating explicitly in the specification.
Related products and applications
Need this profile made to your drawing?
We extrude PC and PMMA diffusers, covers and lenses from your drawing, sample or photometric target. Tooling is developed in-house.
Frequently asked questions
What is the difference between a cover and a diffuser?
A cover protects and finishes; a diffuser is chosen for its optical behaviour. Many covers do both.
Can a cover have an opaque section?
Yes, by two-colour co-extrusion.