As far as we have learnt, there are many famous LED chips brands as following:
The foreign brands: Nichia, Cree, HP, Toyoda GeseiCo, Toshiba, SDK, Philips Lumileds, luxeon, Smileds, Genelite, Osram, Gelcore, Bridgelux, Seoul, Epivalley and etc.
The china mainland brands: Silan, AXT, LM, San’An, Epilight and etc.
The china taiwan brands: Epistar, Huga, Genesis Photonics, Arima Optoelectronics, AOC and etc.
Osram, Cree and Epistar LED chips are widely used in LED displays. Most of LED display companies will buy chips or lamps from them. It is forecasted that China will produce more than 70% LED products for the world LED market, China will become the largest LED chip market at the time in the world. although Osram is of top quality and famous, but the extremely high price scare most customers at present. Cree is of good quality and moderate price, so most high grade customers will choose Cree. The most common-used brands of LED diode are Epistar made in TaiWan and the quality of these LED chips are judged mainly by 5 criteria, which is brightness, attenuation, color uniformity, viewing angle and stability.
Without doubt，China has the strong technology strength and ability to make good quality LED chips now. Also Chips made in China own very big market share in the world LED products market with good reputation due to high cost performance.
Based on the following test results， we found that Cree is the only brand which stabilizes after the first 10000 hours and the attenuation after the first 10000 hours is very minimal.
The brightness (measured by mcd)
|Red lamp||400-600 mcd||400-600 mcd||330-600 mcd|
|Green lamp||1600-2400 mcd||1100-1600 mcd||1200-1700 mcd|
|Blue lamp||300-700 mcd||300-600 mcd||300-650 mcd|
|Whole pixel||2700-4300 mcd||2200-3400 mcd||2450-3450 mcd|
The brightness attenuation after 10000 hours:
|Horizontal||150 degrees||120 degrees||110 degrees|
|Vertical||60 degrees||70 degrees||80 degrees|