Optical characteristics on practical verification for pico-laser-engraved glass light guide plate with concave microstructures

Recent increasing interest in light guide plates (LGPs) based on the advanced manufacturing towards optoelectronics applications has emerged as a potential technology. The aim of this study was to estimate the optical characteristics on practical verification of laser-engraved glass light guide plate with concave microstructures. The case study can use the industrial ability of picosecond laser (pico-laser) technique, a type of ultrafast laser pulses, to directly engrave a glass sheet (Corning Iris® Glass) with functional concave microstructures for fabricating an LGP. Eight small pieces of samples with array of microstructures engraved on different processing conditions were made for measuring optical characteristics before and after the samples were etched by hydrofluoric acid. Here, the engraved 6-inch LGP structures can make light exit from the LGP uniformly. Additionally, the two optimized LGPs were put in a 7.8-inch backlight module where the measured results showed the uniformity of spatial luminance was 0.9. The study demonstrated the one-step process utilizing pico-laser technique, yielding for the design of microstructures of thinner large-sized liquid crystal display (LCD) products in the manufacturing of LGPs for lighted-up in a backlight unit (BLU).