Hsu, C.W., Zhen, B., Qiu, W., Shapira, O., DeLacy, B.G., Joannopoulos, J.D., and Soljacic, M. “Transparent displays enabled by resonant nanoparticle scattering,” Nature Communications 5, 3152 (2014).

Transparent displays have many useful applications: one may turn a regular window into a projection screen, or display navigation and dashboard information while looking through the windshield of a car or plane. A number of technologies have been developed aiming at a subset of these applications, but each method has certain limitations. Researchers in the MIT MRSEC have developed a new type of transparent display using resonant nanoparticle scattering.

By embedding wavelength-selective nanoparticles in a transparent film and by projecting images at the resonant wavelength, a screen is created that scatters most of the projected light while being almost transparent to the ambient light. A blue-color transparent display was experimentally realized this way using silver nanoparticles embedded in a transparent polymer film. The figure on the right (bottom panel) shows the transparent display at work, with a blue MIT logo projected onto the screen from a laser projector. The projected image shows up clearly on the screen, and is visible from all directions. In comparison, the same image projected onto regular glass can barely be seen due to the lack of scattering.

This approach features simplicity, wide viewing angle, scalability to large sizes, and low cost. It can turn store windows, office windows, or the windshield of cars into projection screens.

Transparent Displays Enabled By Resonant Nanoparticle ScatteringM. Soljacic, J. D. Joannopoulos (IRG III)

(a) Resonant nanoparticles are embedded in a polymer film to yield a material that scatters light strongly at the targeted resonant wavelength but is otherwise transparent. (b-d) Cross sections of silver-shell silica-core nanoparticles optimized to scatter blue, green, and red lights. (e) Comparing the transparent projection screen (left) and a regular piece of glass (right). A blue MIT logo is projected onto both, but only shows up on the transparent screen. Three cups are placed behind both screens to visually compare the transparency.

This work was supported primarily by the MRSEC Program of the National Science Foundation under award number DMR-0819762.