Accelerated reliability test method for optics in LED luminaire applications

Abstract

A high accelerated stress testing (HAST) system is introduced to study the photo-thermal stability and reliability of remote phosphor plates, made from Bisphenol-A polycarbonate (BPA-PC) and YA G. Remote phosphor plates, combined with a blue-light LED source, are used to produce white light with a correlated colour temperature (CCT) of 4000 K. Tn this study, the remote phosphor BPA-PC samples of 3 mm thickness were photo-thermally aged at temperature range 80 to 120°C.The blue light is radiated on the sample with light intensity of 13200 W/m 2 • Thermal quenching of the YA G samples is also studied. It is shown that crystallographic structure of phosphor is stable during thermal ageing.