06.18.18

Can You See the Invisible Glass?

Creating nanotextured glass surfaces completely eliminates reflections of all colors of light, making the glass nearly invisible.

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Can You See the Invisible Glass?

A piece of regular glass (lower) shows the reflection of an overhead fluorescent light. A similar piece of “invisible glass” (upper) does not reflect the overhead light and remains completely transparent. The outer edges of both glass pieces are circled in white, for clarity.

The Science

Nanotextured glass surfaces can reduce light reflections to less than 0.2 percent across all visible and infrared light wavelengths. This reduction renders the glass essentially invisible—even at large viewing angles. 

The Impact

These ultra-transparent windows could change cell phones, solar cells, and lasers. The material could enhance the experience of using consumer devices such as smart phones and televisions. Silicon solar cells encapsulated with “invisible glass” outperform conventional devices. How? The material eliminates all reflection losses. Ultra-transparent laser windows with these nanotextures can withstand three times higher optical power than commercial broadband anti-reflection coatings.

Summary

Most optoelectronic components and consumer display devices require glass or plastic covers for protection against the environment. Optical reflections from these encapsulation layers can degrade the device performance or lessen the user’s experience. In this work, scientists used a highly scalable self-assembly based approach to texture glass surfaces at the nanoscale, reducing reflections by such an extent as to make the glass essentially invisible. The nanotextures provide broadband anti-reflection spanning across visible and infrared wavelengths (from 450 to 2500 nanometers) that is effective even at large viewing angles. This technology can be used to improve the performance of solar cells by eliminating reflection losses, which can be as much as 8 percent for glass-encapsulated cells. Ultra-transparent windows with surface nanotextures on both sides can withstand three times more optical fluence than commercial broadband anti-reflection coatings, making them useful for pulsed laser applications.

Contact

Charles Black
Center for Functional Nanomaterials, Brookhaven National Laboratory
ctblack@bnl.gov; (631) 344-4397

Funding

This research used resources of the Center for Functional Nanomaterials, which is a Department of Energy Office of Science user facility, at Brookhaven National Laboratory.   

Publications

A.C. Liapis, A. Rahman, and C.T. Black, “Self-assembled nanotextures impart broadband transparency to glass windows and solar cell encapsulantsExternal link.” Applied Physics Letters 111, 183901 (2017). [DOI: 10.1063/1.5000965]

Related Links

Brookhaven National Laboratory news release: Making glass ınvisible: A nanoscience-based disappearing actExternal link

Chemical & Engineering News article: Nanotextured glass becomes “invisible”External link

United Press International science news: Nanoscale textures make glass invisibleExternal link

Engineering and Technology article: Nanoscale etching renders glass almost invisibleExternal link

Economic Times science article: “Invisible glass” could solve smartphone glare problemExternal link

The Irish News article: Scientists may have found a way to make glass virtually invisibleExternal link

New Atlas materials article: Spiky cones make glass virtually reflection-freeExternal link

American Ceramic Society article: Nanometer-tall cones provide antireflective properties, eliminate glareExternal link

Highlight Categories

Program: BES, SUF

Performer/Facility: University, DOE Laboratory, SC User Facilities, BES User Facilities, CFN

Additional: Technology Impact

Last modified: 11/7/2018 8:55:39 PM