Case Study: Mid IR ND Filter 52%, 32%, 10%, 1%
Data Table |
|
Specification |
Value |
Trans. 52% (OD 0.3) |
1600 – 5000 nm, T=52 +/- 4% |
Trans. 32% (OD 0.5) |
1600 – 5000 nm, T=32 +/- 3% |
Trans. 10% (OD 1) |
1600 – 5000 nm, T=10+/- 2% |
Trans. 1% (OD 2) |
1600 – 5000 nm, T=1+/- 0.3% |
Substrate |
Silicon |
Dimensions |
50 mm |
Thickness |
1.5 mm |
Scratch/Dig |
40/20 |
Quantity Per Year |
5 of each |

Case Study: Design and manufacture of custom Neutral Density Filters
Customer Challenge: We were approached to manufacture a range of 4 custom neutral density filters across the near and mid infrared range for a space application. As with most neutral density filters the challenge lay in developing a “flat” design that can be deposited accurately that would meet the +/- tolerance on this wide wavelength range.
Vortex’s Solution: We began this particularly tricky challenge at the design stage, by calculating accurate data for the selected coating materials. This is a key stage in the process since experienced based design simulation can save a lot of unnecessary coating runs. To save additional time we used an off the shelf Silicon substrate
Outcome: Vortex successfully delivered the range of custom neutral density filters, each meeting the required transmission levels of 52%, 32%, 10% and 1%. The customer was delighted with the results and the filters were delivered with full test reports on time and avoided any delay to the tight customer schedule, particularly import for space missions!
Our ability to develop small custom batches of ND filter to a tight unmoveable deadline, is made possible by utilising our range of coating machines and extensive understanding of the chosen coating materials. This makes Vortex an excellent choice for low and high volume highly specialised ND filters for custom applications.