Reducing the thickness of quantum-dot-incorporated backlight units (QD-BLUs) is an important issue for QD-incorporated display because of various optical sheets and additional barrier films. However, critical challenges such as the aggregation and vulnerability of QDs and the need for a binder for patterning have emerged. Here, we propose a thermally stable and PL-improved microlens/QD-siloxane film (ML/QD film) by UV imprinting of a microlens array on the film surface. Compared to the neat and diffuser/QD films, the thickness of the ML/QD film decreased by 25% to realize white PL, resulting in less QD usage. The ML/QD film showed superior, long-term thermal and moisture stability and a wide color gamut (109% related to NTSC). A glass-fabric reinforced siloxane hybrid (GFRH) film with a high haze value of 92% was fabricated by the refractive index contrast of methacrylate oligo-siloxane resin with glass-fabric. Hazy GFRH (H-GFRH) exhibited a uniform diffusion of light (diffuser sheet) as well as outstanding thermomechanical properties (polymer substrate). The synergetic advantages of the ML/QD film on H-GFRH substrate will be beneficial for the large-scale and thin white QD-BLUs in display applications.