Nichia has issued a public warning about patent infringement, which relate to its Red-Emitting Phosphors. Without Nichia’s authority, CASN phosphor , S-CASN phosphor and LEDs using these phosphors, have been manufactured in large quantities. It expects that these patents will be respected.
Nichia points out that it has many (jointly-owned patent) applications in Japan, USA, Europe, China, Korea, and Taiwan concerning these particular phosphors represented by the general formula of CaAlSiN3:Eu These relate to CASN phosphor, S-CASN phosphor, and LEDs using these phosphors. The company lists 15 Japanese, US, and European, patents related to the specific phosphor formulations.
Presumably, the company found products from another company that utilize the same phosphor formulation to emit red light. Nichia did not divulge whose products were allegedly infringing its red emitting phosphor patents.
Nichia's list of relevant patents includes: JP4414821, JP4415065, JP4422653, JP4511849, JP4511885, US7252788, US7273568, US7432647, US7476337, US7476338, EP1568753, EP1630219 .