A note on solution to overheating damage of plastic optical fibers in daylighting system

Abstract Due to low cost and flexibility, Polymethylmethacrylate (PMMA) plastic optical fibers were widely used in the daylighting system. However, the overheating damage caused by infrared thermal effects has seriously affected the safety of PMMA optical fibers. To solve this problem, this work experimented three configurations in Tibet, which include homogenizer, infrared light filter, and liquid water. The analysis showed that the infrared light filter and liquid water are complementary in filtering infrared light, which filter infrared light in the range of 780-1100 nm and 1100-2500 nm respectively. The experimental results demonstrated that the PMMA optical fibers can transmit high solar flux safely under the combined protection of homogenizer, infrared light filter, and liquid water.