Pixel Pyramids May Improve LEDs

A team from the University of California in Los Angeles believes that a structure of pyramid-shaped pixels may boost the lateral resolution of organic LED displays by a factor of three or four. Yang Yang and Shun-Chi Chang have described in the Aug. 14 issue of Applied Physics Letters how electroluminescent organic films deposited on tetrahedrons could realize the advantages of the technology while avoiding the manufacturing problems attributable to shadow masks.

The researchers' deposition technique, which they demonstrated using Alq₃ on a substrate with a two-sided ridge structure, takes advantage of the line-of-sight nature of vapor-phase deposition. Because only one set of sides would be presented to the vapor flux at a time, each pixel would receive red-, green- and blue-emitting films that shared the same emission area without the added complexity and expense of masking.