Ultra-hard optical diamond coatings

Challenge 

Transparent coatings with scratch protection often determine the usability and service life of optical components. In many sectors, these are combined with AR layers. Existing solutions are reaching their limits, they are susceptible to wear and tear and clouding due to abrasion. The aim of the project is the development of ultra-hard optical diamond coatings for use in AR systems.

Solution 

Multilayer systems consisting of a diamond layer and low- or medium-refractive-index layers are to be designed and researched in order to develop ultra-hard optical diamond coatings for AR applications. The novel aspect of the coating system to be investigated here is the deposition of very thin and extremely smooth diamond coatings with the lowest possible absorption coefficients. The coating processes (HFCVD at the Fraunhofer IST, PECVD at research partner Uni Hasselt) must also be developed in such a way that very uniform layers with high layer growth rates are possible. 

Added value 

Transparent, ultra-hard diamond coatings in AR coating systems should lead to abrasion-resistant surfaces. By the end of the project, findings on the wear resistance of the coating systems on different substrates should be available, demonstrating customer benefits with regard to the unsurpassed hardness of diamond and thus high mechanical load capacity also for optical applications.