Neutral Density Filters

Neutral density filters manufactured from Schott® glass or Hoya® glass give a good range of ND filters from a solid glass available as an absorptive neutral density filter.

Absorptive Neutral Density Filters from Stock

Reflective Neutral Density Filters from Stock

There are many applications for neutral density filters being used as a good attenuator. They are useful for light control applications for measuring instruments and exposure control in imaging. They are often used in laser and photometer applications where excessive power can cause damage or inaccurate results for electronics they reduce the intensity of light.

Absorptive Neutral density filters made from the following glasses: Schott NG-1, NG-3, NG-4, NG-5, NG-9, NG-10, NG-11 and NG-12 also Hoya ND-70, ND-50, ND-40, ND-25, ND-13, ND-03 are all available covering the optical density range OD 0.10, OD 0.15, OD 0.20, OD 0.30, OD 0.40, OD 0.50, OD 0.60, OD 0.70, OD 0.80, OD 0.90, OD 1.0, OD 1.30, OD 1.60, OD 2.0, OD 2.30, OD 2.60, OD 3.0, OD 3.30, OD 3.60, OD 4.0, OD 4.30, OD 4.60, OD 5.0 with transmission 0.001% to 79%.

Custom neutral density filters are manufactured to specific optical densities and transmission. These are controlled by the thickness of the glass by polishing the filter to a required transmission or density at specific wavelengths. These filters are calibrated to traceable NPL standards with a full spectral trace and spot reading on request. Each filter can also be labelled with the density or assembled into mounts.

UV Inconel coated neutral density filters on fused quartz or glass depending on the wavelength range are available in all densities.

Didymium filters Schott BG-20 , Hoya V-10, V-30 and Holmium filters Hoya HY-1 are multi-band calibration filters are used for checking the wavelength calibration and often used in addition to the ND filter sets.