Nano-patterned Anti- reflective films
All transparent media reflect some of the light incident on their surfaces. The reflection is caused by the abrupt change in the refractive index at the interface between two media. With the help of microstructured surfaces (see illustrations below), the reflection can be reduced considerably. Surface structures which are smaller than the wavelengths of light cannot be resolved by the incident light - the structures lead to a continuous transition in the refractive index at the interface and reduce the reflectance of a glass pane from about 8 % to less than 1 %.
In architectural glazing or solar collectors, reflection-reducing surface structures can be applied in order to increase solar gains. The approach can also be used to suppress disturbing visible reflections
With the aim of developing a favourably priced production process for large-area anti-reflective surfaces, three Fraunhofer Institutes have combined to form a consortium with complementary areas of competence including:
Within the joint project, diverse technological approaches to obtain structured surfaces are being followed. This means that solutions to reduce reflection can be individually optimised.
Contact persons in each Institute
Institute for Solar Energy Systems ISE