Sheng Liu

A practical introduction to state-of-the-art freeform optics design for LED packages and applications By affording designers the freedom to create complex, aspherical optical surfaces with minimal or no aberrations, freeform design transcends the con…

Since the first light-emitting diode (LED) was invented by Holonyak and Bevacqua in 1962, LEDs have made remarkable progress in the past few decades with the rapid development of epitaxy growth, chip design and manufacture, packaging structure, proce…