Light Guide Plate Based on Sub-micron Gratings

摘要

A novel light guide plate (LGP) with sub-micron gratings (SMGs) on its upper surface is proposed to control the illumination angle and its initial structure of LGP is given. The periods of SMGs are 0.651um, 0.516um and 0.433um for the LED light sources transmit out vertically with the incidence angle 45 deg under the total internal reflection condition. The transmission efficiencies vary between 2 percent and 43 percent when the depth of grooves of SMGs changes between 0.05 urn and 0.9 urn by using rigorous coupled-wave theory (RCWT). The results show that the LGP utilizing the characteristics of the SMGs can control the transmission angle and get homogeneous output.