Northumbria Optical Coatings Ltd

Filter Sizes

Our lowest cost standard filter size is 25mmØ x 3.3–7.0mm thick, mounted in a polyamide holder, with 21mmØ clear aperture. The particular grade of material used for the holder has been chosen because it has a high maximum operating temperature and is stabilised against infra-red and ultra-violet radiation. (Note: Useful aperture for some blocking filters is different and the holders for these are made of black anodised aluminium).

Other standard sizes are 23mmØ x 1.0mm thick, 25mmØ x 1.0mm thick and 25.4mmØ x 1.0mm thick (all un-mounted).

We also hold tooling for other common sizes including 10mmØ, 12mmØ, 12.7mmØ, 15mmØ, 35mmØ, 50.8mmØ and 76.2mmØ

Custom Sizes

We can manufacture coatings from 2mm x 2mm square up to ~100mmØ, depending on coating type.

For custom sizes we manufacture on 25.4mmØ, 50.8mmØ or 76.2mmØ discs depending on filter type and quantity required and then cut as required, e.g. semi-circular, quadrants, squares, rectangles, hexagons or custom shapes.

Generally, where circular filters are required we tend to manufacture on pre-cut discs. This is due to the difficulty and time involved in cutting and edging into circles. If large volumes of circular filters <9mmØ are to be purchased, it is worth considering the possibilities of using cut hexagons as this can help reduce costs.

In addition, where specialist applications are required (e.g. operating at cryogenic temperatures) we can manufacture on custom shaped pre-cut substrates by using specialist tooling.

Filter Thickness

Our standard thickness for filters is 1.00mm ±0.1mm, but we have coated substrates as thin as 0.1mm and as thick as 10mm.

If filters are to be cut to smaller shapes and sizes it is recommended that you use 0.50mm, as this produces a cleaner cut edge and higher yield.


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Need a bespoke product?

We have a wide range of filters available for purchase through our online catalogue. If you canít find the product you need, please click here to contact us and discuss bespoke orders.

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