Frequently Asked Questions

Knight Optical offers an extensive custom optic service thanks to our many years of experience in the industry. We are able to supply ND filters cut to sizes and shapes to fit individual application and mount filters where applicable.

Knight Optical offers stock absorptive ND filters in 12.5mm and 25mm diameters, and 50x50mm squares manufactured from high quality glass.

Neutral density filters are used in applications such as spectroscopy, machine vision, ellipsometry and photography.

Each filter is available with blocking between 0.1 and 4.0 OD and are available to purchase direct from this page.

Glass Neutral Density filters attenuate light by absorption just like the gelatine neutral density filters.

You May Also Like