Neutral Density Filters
Neutral Density or check filters have many applications but are generally used in the attenuation of energy covering the NUV-VIS-NIR band. Because the attenuation is achieved by a combination of absorption and reflection, the filter can be used as beamsplitters in some applications.
TMF manufactures a range of ND filters covering ND 0.1. to ND 3. and can be optimised at any wavelength from 350 to 1100nm.
The relationship between neutral density ND and transmission T is ND = log 1/T
To achieve neutrality of attenuation with wavelength, nickel chrome alloy is used in their construction. This material is extremely durable when applied to quartz and glass, less so on plastic substrates.
TMF offer three configurations:
The required density applied uniformly to the entire surface.
This is a graded circular ‘spot’ being most dense at the centre and normally decaying to zero at the outside of the substrate.
ND Filters can be applied in discrete steps across the substrate
Please call or email us to discuss any variations in standard coatings that you may require.
Product Technical Details:
- Large Area Dielectric Beamsplitters
- Beamsplitter Coatings
- Anti-Reflection Coatings
- Metal Coatings
- RFI shielding, Anti-static and Heated Window Coatings
- Fibre Optic Coatings
- UV Mirror Coatings
- Neutral Density Filters
- Dielectric Mirrors
- Unbreakable Plastic Mirrors
- Front Surface Mirror
- Large Front Surface Mirrors
- Cleaning Front surface Mirrors
- Why use Front surface Mirrors?