I’ve written several posts about the legal wrangling between Japanese LED maker Nichia Corp. (Nichia) and its Korean competitor Seoul Semiconductor Company, Ltd. (Seoul). Last month Nichia opened a new front in the companies’ patent wars with a suit filed in the Eastern District of Michigan.
The complaint alleges that Seoul’s Acriche brand light sources (pictured above) contain LEDs that infringe Nichia’s U.S. Patent No. 6,870,191 (‘191 patent).  The Acriche product line has been getting some press because it supposedly is the first LED product that does not require an AC/DC converter and therefore can plug directly into ordinary AC electrical outlets.
The complaint also names Avnet, Inc., one of Seoul’s authorized distributors of LEDs, as a defendant. Nichia is requesting an injunction and damages, as well as a complete list from defendants of the entities from whom they purchased any allegedly infringing products.
The ‘191 patent is directed to an LED where the surface of the substrate, or backing material, is roughened with recesses or protrusions. The roughened surface serves to scatter or diffract the light generated in the semiconductor layers of the LED and increases the LED’s output power.
This patented structure alleviates the problem created when light from the light emitting region of the LED enters the inner surface of the LED’s conductive material or the outer surface of the substrate at an angle too large for efficient propagation and effective transmission.
With litigation in Korea, Japan, California, Michigan and the U.S. International Trade Commission involving LED patents, LED design patents and even false advertising claims, we’ve almost reached the point where a new lawsuit between Nichia and Seoul is no longer news.