What this application demands
Stage and architectural lighting puts optics in an environment that is optically simple and thermally brutal. A dichroic colour plate sits a short distance from a discharge lamp or a high-power LED array, absorbs a small fraction of an intense beam, and is expected to keep its colour for thousands of hours. The engineering problem is nearly all thermal.
Colour consistency is the second requirement. A fixture that uses several colour plates has to produce the same colour from one fixture to the next and from one production batch to the next, which means the coating's spectral transmission has to be reproduced accurately rather than approximately.
Specifications we recommend
| Component | Typical specification | Why |
|---|---|---|
| Dichroic colour plates | Hard-coated transmission filters matched to the colour card | Stable colour with minimal absorption, so less heat is trapped in the glass |
| GOBO and pattern plates | Heat-resistant substrate, coated or etched to the pattern | Survives the focal-plane heat load of a projection fixture |
| Cold mirrors | Reflects visible light while transmitting infrared | Removes heat from the beam instead of absorbing it |
| Heat-control filters | IR-absorbing or IR-reflecting designs sized to the fixture | Protects shutters, gobos and downstream optics |
Failure modes we design against
Thermal cracking is the classic failure and it usually begins at an edge chip or a mounting stress point. Edge quality and mounting design matter as much as the material's thermal shock resistance. Colour drift over service life is the second issue: a coating that absorbs rather than reflects the rejected band heats up and shifts its own spectrum, so designs that minimise absorption are inherently more stable.
Frequently asked questions
Can you match an existing colour plate?
Yes. Send the sample or its measured transmission curve and we will match the spectral performance, including the colour-card reference if you use one.
What substrate do you recommend for GOBOs?
It depends on the fixture's focal-plane temperature. Send the lamp type and the distance from the gate and we will recommend a substrate and coating combination.