Ultra-Hard-Coated filters

Already in 2005, DELTA successfully managed to produce optical filters with the Ultra-Hard-Coating technology. DELTA has then lead the way towards an ever increasing complexity and performance of optical filters.

Environmental test performed on an UHC filter.

What is an Ultra-Hard-Coated filter?

Ultra-Hard-Coated (UHC) filters are produced with an advanced plasma process that enables a much higher packing density than traditional hard coatings.

The coating is deposited on one single substrate and hence does not make use of glue. The resulting filter is exceptionally robust and can stand intense light and humidity without losing its performance.

The graph to the right shows the extreme stability and robustness of the Ultra-Hard-Coated filter. After having undergone an environmental test, the spectrum of our UHC filter is not altered.

SEM picture of the surface of an UHC filter

The SEM (Scanning Electron Microscope) picture taken at a x32000 magnification shows the perfect surface and density of the UHC surface that makes DELTA's Ultra-Hard-Coated filters the best and robust filters you can find on the market.

The smooth surface feature boost the following advantages:
- reduced stray
- no voids: shift-free coating

What are the advantages of Ultra-Hard-Coated filters?

• Best spectral stability (no spectral drift)
• Increased lifetime
• Excellent adhesion of the coating on the substrate
• Possibility of depositing very thick layers and increased complex functions
• Optimal mechanical stability
• Minimal water uptake