Anti-Reflection Coating for Curved and Rough Surfaces

Reduces Optical Reflection While Increasing Light Transmission Through Nearly Any Substrate

This anti-reflection coating reduces optical reflection and increases light transmission through geometrically complex optical surfaces. Consumer demand for anti-reflective properties continues to need for improved applications such as improving light conversion efficiency of solar cells, increasing transmittance of optical lenses, eliminating ghost images on flat-panel displays, reducing glare from automobile dashboards, to name a few examples. The global anti-reflection coating market should reach $7.5 billion by 2025. Available vacuum-based anti-reflection coatings are burdened by high costs, limited raw materials for manufacturing, and low light transmission. More importantly, coating nonplanar surfaces is challenging, which limits the scope of application for anti-reflection coatings. Available anti-reflection coatings are difficult to apply to curved or enclosed concave surfaces.

Researchers at the University of Florida have developed an efficient, effective system that applies uniform anti-reflection coatings to nearly any nonplanar surfaces. A uniform, single layer of silica nanoparticles applied to a surface through a simple self-assembly approach and then cured with vapor creates a durable anti-reflection coating covering both internal and external surfaces of the optical components.

Application

Efficient, scalable process for applying a durable anti-reflection coating onto nearly any shaped surface, including those with complex geometries

Advantages

• Employs a wet application approach, making the coating simpler, faster and cheaper than vacuum-based approaches
• Applies the coating with a simple dip technique, increasing the range of products that can be coated
• Uses easily-accessible raw materials, creating a scalable system that is inexpensive to commercialize
• Incorporates a simple vapor-curing step, increasing the durable properties of the anti-reflection coating

Technology

An electrostatics-assisted, colloidal self-assembly process allows uniform nanoparticle anti-reflection coatings deposits onto geometrically complex optical surfaces. A single layer of negatively-charged silica nanoparticles adhere to a positively-charged surface to form the optical coating. The monolayer anti-reflection coating improves light transmission, through surfaces with various geometries, to more than 97 percent transmission for wavelengths between ~500 and ~800 nm. The addition of a simple vapor-treatment step enhances adhesion of the nanoparticles, significantly improving the strength and durability of the anti-reflection coating.