By Meghan Bialt-DeCelie ‘19

Displays of all commonly used electronics such as smartphones, televisions, and laptops all suffer from glare on their glass surfaces. Glass and clear plastics are transparent, but they are still visible due to a small amount of reflection of light caused by the difference between the refractive index of the surface and the rest of the material. Antireflective coating and screens currently exist in the market; however, they tend to work within a small range of wavelengths and angles of light.

Researchers led by Andreas Liapis, PhD from the Brookhaven National Laboratory developed a scalable process to make textured, glare-preventing glass at the nanoscale. They took inspiration from nanotextured surfaces of insect eyes and wings. Nanoscale cones as a texture offer a slower gradient of change in refractive index between the medium of the air and the medium of the glass. This provides a highly effective antireflective surface across a much wider range of wavelengths and angles of light. Techniques for developing this kind of surface must be highly scalable to make this applicable in the consumer market of electronics. Researchers used self-assembling block co-polymers to form the nanocone patterns on the glass surface. Based on the Maxwell-Garnett effective-medium model, they found that increasing the height of the nanocones reduced the reflection.

Using this process, scientists were able to reduce the reflection of glass to as little as 0.2%. This provides not only a clearer display of electronics, but also improves the efficiency of solar cells that are enclosed by glass.

References:

1. A. Liapis, A. Rahman, and C. Black, Self-assembled nanotextures impart broadband transparency to glass windows and solar cell encapsulants. Applied Physics Letters 111, 18 (2017). doi: 10.1063/1.5000965.
2. Image retrieved from: https://commons.wikimedia.org/wiki/File:Roy_Thomson_Hall_glare.jpg