Reliability and Lifetime Assessment of Optical Materials in LED-Based Products

Lumen depreciation is one of the major failure modes in light-emitting diode (LED) systems. It originates from the degradation of the different components within the system, including the chip, the driver, and the optical materials (i.e., phosphorous layer). The kinetics of degradation in real-life applications is relatively slow, and in most...

Quality and Reliability in Solid-State Lighting: Qua Vadis?

In the past 4 years we have witnessed a change in quality and reliability to make the marked introduction of solid-state lighting (SSL) successful. LED penetration levels have reached values of 10–30%, depending on the application. The number and variety of LED packages and, thus, associated LED-based products, have significantly increased in...

LED-Based Luminaire Color Shift Acceleration and Prediction

Color stability is of major concern for LED-based products. Currently, much effort is done on lumen maintenance, and for color shift, no agreed method currently exists, be it from testing or from prediction side. To investigate the physics of color shift, we present experiments of each individual part failure of each individual part that are...

Corrosion Sensitivity of LED Packages

The penetration of solid state lighting applications is due to the promise of a low-cost reliable solution by means of application of low- and mid-power LEDs. These LED packages are manufactured by making use of new processes and materials which in principle introduces a series of known and unknown failure modes. Corrosion is a specific failure...

Statistical Analysis of Lumen Depreciation for LED Packages

Commercial claims for LED-based products in terms of lumen maintenance are fully based on TM-21 extrapolations using LM-80 data. This chapter indicates that there may be a risk in doing this as TM-21 only relies on the behavior of the average LED degradation, instead of taking into account the degradation of all individual LEDs. Therefore, we...

The Next Frontier: Reliability of Complex Systems

Traditional lighting is focused on the prevention of hardware failures. With the trend toward controlled and connected systems, other components will start playing an equal role in the reliability of it. Here reliability need to be replaced by availability, and other modeling approaches are to be taken into account. Software reliability can only...

Lightning Effects on LED-Based Luminaires

This chapter gives an extensive overview into the nature of the environment that luminaires and thus LEDs are subjected to during the event of a lightning stroke. Direct lightning stroke almost always results in instant damage for low-voltage connected devices, except in “extraordinary circumstances” where random components may survive. This is...

Reliability Prediction of Integrated LED Lamps with Electrolytic Capacitor-Less LED Drivers

This chapter investigates the reliability of the integrated LED lamps with electrolytic capacitor-less LED drivers. Firstly, the impact of the interaction between the degradations of the LED light source and the driver on the lumen depreciation is studied. The electronic-thermal simulation was carried out to obtain the history of temperatures of...