Micro-Optics Homogenize Light

Researchers in Germany have solved a difficult technical problem in producing pure, uncolored white light by creating a nanostructured optical material from inorganic and organic components.

Because white light is produced by mixing red, green and blue light together, until now it has been difficult to produce a pure light beam without any of the colors being visible.

"For a long time, producing white light with no peripheral color effects was an almost unsolvable technical problem," said Dr. Michael Popall of the Fraunhofer Institute for Silicate Research ISC in Wurzburg. "White light is produced by mixing the complementary colors red, green and blue. Undesirable refraction occurs with conventional beamer technology, resulting in colored streaks on the periphery of the projection."

This technology delivers not only brilliant color, but also pure white. "The tiniest of red, blue and green light diodes on the most condensed space produce the light, which is then bundled and homogenized by the nanostructured Ormocer® optics," said Popall, who was deeply involved in the development of the material.

"Ormocers are an ideal material for the production of micro-optics," the researcher said. "They are not only superior light conductors, but are also easy to process – not as brittle as glass, and not as pliant as polymers."

Ormocers are a hybrid of inorganic and organic components that are networked at the molecular level. This material makes it possible to realize things inconceivable even a couple of years ago: Ultraflat and ultrasmall optics for microcameras or beamers that fit into a pants pocket.

The design of the new optics was developed by experts at the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena.

"Thanks to close collaboration among chemists at ISC and the physicists and engineers at IOF, we have succeeded in developing Ormocer tandem arrays with two-sided and symmetrically arranged microlens configurations, which allow the light from light diodes to be projected with pinpoint accuracy and without refraction errors," Popell said. The technology is on the verge of being introduced on the market.

The researchers will present the technology Feb. 17-19 at nano tech 2010 in Tokyo (Booth F-14-1).

For more information, visit: www.fraunhofer.de/en/