High-efficiency quantum dot remote phosphor film

We report a high-efficiency quantum dot (QD) film for high color gamut edge-lit LCD backlights. On the film's input surface, an array of asymmetric microprisms is used to preserve the large off-axis angle of the incident blue light. On the exit surface, the retroreflective microprisms retain blue light inside the film. The extended optical path effectively enhances the blue light's probability to hit QDs and generate downconverted wavelengths. When not using any volume scattering particles, fewer QDs are needed to re-emit higher power green and red light, which helps lower the material cost. (C) 2015 Optical Society of America