We propose and demonstrate a metal-dielectric thin film that delivers low reflection and high absorption over the entire
visible spectrum. This thin black film consists of SiO2/Cr/SiO2/Al layers deposited on glass substrate. Measured
reflectance and absorptance of the black film are 0.7% and 99.3%, respectively, when averaged over the range 380-780
nm. The total thickness of the black film is only about 220 nm. This thin black film can be used as a thin absorbing layer
for displays that require both broadband anti-reflection and high contrast characteristics.
We proposed and demonstrated a simple approach for designing and developing blue-excitation-light passing and
phosphor-yellow-emission-light reflecting dielectric multilayer to enhance the forward efficiency of Y3Al5O12:Ce3+
(YAG:Ce) yellow phosphor on top of a blue InGaN LED cup. When inserting a modified quarter-wave films of alternate
high- and low-refractive index dielectric films (TiO2/SiO2) into the interface between a YAG:Ce phosphor layer and a
glass substrate, enhancements of the efficiency and luminous efficacy of the forward white emission become 1.64 and
1.95 times that of a conventional phosphor on top of a blue LED cup with a lower correlated color temperature (<
We propose and demonstrate weak-microcavity organic light-emitting diode (OLED) displays that deliver both a high
light-extraction efficiency and wide viewing-angle characteristics. A single pair of low- and high-index layers is
inserted between indium tin oxide (ITO) and a glass substrate. The electroluminescent (EL) efficiencies of discrete red,
green, and blue weak-microcavity OLEDs (WMOLEDs) are enhanced by 56%, 107%, and 26%, respectively with
minimal changes viewing angle and EL spectra characteristics. The color purity is also improved for all three colors.
Moreover, we fabricated full-color 128×160 passive-matrix bottom-emitting WMOLED displays to prove their
manufacturability. This design is realized by simple one-step 20-nm etching of the low-index layer of red/green subpixels.
The EL efficiency of white color in the WMOLED display is 27% higher than that of a conventional OLED