Custom Circular Windows

Circular optical windows are flat, parallel-sided optical components with a circular aperture. They are used to seal optical systems while maintaining optical transmission, or to protect optical components from environmental factors without introducing optical power. Windows are essential in applications requiring environmental sealing, vacuum chamber viewports, laser beam windows, and protective covers.

Unlike lenses or prisms, circular windows have zero optical power - both surfaces are flat and parallel. The primary function is to maintain optical transmission while providing physical protection or environmental isolation. Optional anti-reflective (AR) coatings can be applied to both entrance and exit faces to maximize transmission and minimize reflective losses.

If you need larger diameters, custom thicknesses, specialized materials, coatings, or specifications not available in the configurator, please contact us at [email protected] for a custom quote.

Note: It costs about as much to make one custom window as it does to make ten, hence the minimum order quantity is 10 pieces. Large price drops occur as volume increases to 100 units.