UV LED lifetime measurement is a challenging yet essential task required for component comparison and product development. Typical batch test systems utilize specialized integrating spheres suitable for UV light measurements and require periodic opto-electrical measurements at specific junction temperatures, which are time-consuming, labor intensive, and costly. Measurement uncertainties can be introduced due to imprecise positioning and manual operation. Typically, measurements using the integrated sphere provide the absolute intensity integrated over the solid angles, providing non-directional radiometric output. While such measurements provide the basis to set lifetime trends, ageing characteristics can be directional, varying with LED emission angles, playing an important role in determining device lifetimes depending on specific applications. We propose the design of a fully-automated lifetime test system, equipped with robotics, driven using artificial intelligence tools suitable for production scale testing of UV LEDs. This system allows for rapid, repeatable, relative optical measurements without the use of an integrating sphere, hence reducing capital and labor costs. The system is equipped with location sensors and learning algorithms which permit precise positional control across the three dimensions making it versatile for use with different types of LED optics at varying heights. It enables radiometric output measurements in a pre-determined angular grid around the LED, providing output degradation data as a function of emission angle in near field without the need for a goniometric apparatus. The system is designed to be easily scaled to accommodate larger arrays, enabling a flexible and cost-effective solution.
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