In a University of Maryland study, researchers at the A. James Clark School of Engineering have demonstrated that windows made of transparent wood provide more consistent natural lighting and better energy efficiency than glass.
The wood lets through just a little less light than glass, but a lot less heat, said Tian Li, the lead author of the new study. “It is very transparent, but still allows for a little bit of privacy because it is not completely see-through," Li said.
Channels in the wood transmit visible-light wavelengths while blocking the ones carrying heat. The cell structure "bounces" the light around slightly, creating a "haze" that keeps light from shining directly in a person's eyes.
The team’s findings were derived, in part, from tests on tiny model house, which had a transparent wood panel placed in the ceiling. The study revealed that the light was more evenly distributed around a space with a transparent wood roof than a glass roof.
Also: Learn about how NASA Measures Distortion in Optical Windows.