Infrared Optical Filters
IR Interference Filters: 1.5 - 20 µm

Filter Sizes

Our standard size is nominally 25mm diameter x 3-7mm thick mounted in a polyamide holder with 21mm diameter clear aperture (Note: Useful aperture for some blocking filters is different and the holders for these are made of black anodized aluminum). The particular grade of material used for the holder has been chosen because it has a high maximum operating temperature and is stabilized against infra-red and ultra-violet radiation. Other common sizes are 23mm diameter x 1 mm thick, 25mm diameter x 1mm thick and 1 inch diameter x 1mm thick (all un-mounted).

Custom Sizes

From 2mm x 2mm square up to ~50mm diameter, depending on type of coating. For custom sizes we manufacture on 25.4mm discs and then cut as required. For example, semicircular, quadrants, squares, rectangles or custom shapes. However, in general, where circular filters are required we tend to manufacture on pre-cut discs. In addition where specialist applications are required (e.g. operating at cryogenic temperatures) we can manufacture on the custom shaped pre-cut substrates by using specialist tooling.

Northumbria Optical Coatings Ltd (NOC) was established in 1995, specializing in the design and manufacture of Infrared Optical Filters and Coatings, covering the spectral range 1.5µm – 20.0µm. Before 1995 NOC operated as a business unit for Rolls Royce International Research & Development based in Newcastle upon Tyne. NOC offers competitively priced standard and non-standard filters which are used in many applications including environmental monitoring, analysis and control of gaseous effluent, analysis of vehicle exhaust gases, ozone layer monitoring, night vision systems and space applications. Contact EOC for more information.