Degradation analysis of secondary lens system and its effect on performance of LED-based luminaire

•The aged polycarbonate lens increases the radiant flux.•The lens holder degradation is the major contributor to the changes of the optical parameters.•The degradation of the lens system leads to a significant impact on color maintenance.

Degradation of a secondary lens system and its effect on LED-based luminaire performance are investigated. A polycarbonate plastic lens system is selected as a test vehicle. The lens system is aged under an actual user condition using high power warm white LEDs. The spectral power distributions (SPDs) of the LED/lens assembly are obtained before and after 9500 h of continuous operation. A detailed SPD analysis is followed to identify the most critical parameter of the lens system degradation.