Optimization of light conversion efficiency in inkjet-printed cadmium selenide quantum dot layers

Color conversion layers are extensively utilized in flat panel display technology for their capacity to provide a wide color gamut and improved resolution, along with exceptional design flexibility. The uniformity and thickness of cadmium selenide (CdSe) quantum dot (QD) films are often difficult to control in the preparation of color conversion layers. Interestingly, it is possible to precisely deposit QDs by inkjet printing to improve material utilization. Color conversion layers with optimized spectral properties and light conversion efficiency are successfully prepared by inkjet printing. We employ inkjet printing technology to fabricate CdSe QD color conversion layers with precise control over layer thickness. The effects of layer thickness on spectral properties and light conversion efficiency are systematically investigated. It is found that a layer thickness of 5.5 μm achieves the highest light conversion efficiency at 20.4%, with efficiency decreasing as thickness increases to 6 μm. In addition, it is observed that blue light transmittance decreases from 47.2% to 11.4% with increasing layer thickness, highlighting the importance of thickness control in optimizing spectral properties.