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Updated: Apr 30, 2026

Development of an Innovative LED-based Illumination Device for In Vitro Application of Photodynamic Therapy with Rose Bengal
Published on: September 12, 2025
Side-illuminating LED luminaires with accurate projection in high uniformity and high optical utilization factor for
Abstract:
A novel light luminaire is proposed and experimentally analyzed, which accurately projects light into a large rectangular area to achieve uniform illumination and a high optical utilization factor at the target. Side-illuminating luminaires for large-scale illuminated area are typically set with an elevated tilt angle to enlarge the illuminated area. However, the light pattern is bent thereby reducing the uniformity and optical utilization factor at the target. In this paper, we propose an efficient and useful approach with a rotationally symmetric projection lens that is trimmed to adjust the bending effect and to form a rectangular illumination light pattern on the ground. The design concept is demonstrated and verified. Several potential applications such as highly uniform illumination with fitting shapes for sport courts are analyzed and discussed.
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