Session Index

This study is to use dry etch,wet etch and light extraction layer methods to rough the light emitting surface (p-GaP) of the red LED to reduce the internal total reflection phenomenon of the LED to increase the light output rate.

 

Quantum dots light-emitting diodes (QLEDs) based on MoS2 QDs have been demonstrated. Exhilaratingly, we have succeeded in fabricating the low-toxic white light emitting diodes which have not been done so far. This work may open the route for using transition metal dichalcogenides (TMDs) QDs as light emitting devices.

 

In this study, we introduce new process of partially alignment liquid crystal modulator used in the tuning the correlated color temperature (CCT) of white light-emitting diodes (LEDs). The liquid crystal modulator with partially alignment is realizing a CCT-tunable white light whose CCT can be accurately controlled.

 

In this article, we investigate the optical frequency response of GaN-based blue LED with and without electron retarded layer (ERL). The EQE with ERL were improved 9.15 % with ERL, however the optical frequency response decay decreases seriously due to the poor electron transport caused by ERL structure.

 

Deep-red Mg2TiO4:Mn4+ phosphor was synthesized by solid-state reaction at 1300°C for 5 h. The influence of Mn4+ concentration on the luminescence properties of phosphor was discussed. Under UV and blue light excitation, Mg2TiO4:Mn4+ exhibited red luminescence at wavelengths 661 and 677 nm, which is potential for white light-emitting diode application.

 

A novel p-electrode design for AlGaN deep ultraviolet light-emitting diodes (DUV-LEDs) is proposed. The 9-finger-design DUV LED exhibits higher light output power, external quantum efficiencey and better current spreading uniformity. A 1.65 mW at 20 mA is obtained corresponding to a performance enhancement of 154% compared with others DUV LEDs.

 

The p-up GaInP thyristor has an ITO window layer can increase the output power of 497% and reduce the turn-on voltage of 0.74 V. But the n-up AlGaAs thyristor has an ITO window layer only increases the output power of 21% and increase the turn-on voltage of 6.19 V.

 

We demonstrate inverted perovskite light-emitting devices based on ZnO nanocrystals and cesium lead bromide film as the electron injection and emission layers, respectively. Furthermore, polyethyleneimine ethoxylated and an ionic polyfluorene derivative containing trimethylammonium hexafluorophosphate groups were introduced as the electron transport bilayer to enhance device performance.

 

We report that the optical microcavity/Purcell effect, in addition to enhancing light extraction, can also be judiciously used as an additional/independent approach for boosting the radiative transition rates/emission quantum yields of thermally activated delayed fluorescent emitters in devices particularly for the spectral ranges more difficult for high emission quantum yields.

 

Fluorescent substrates have been fabricated for white organic light-emitting diodes (WOLEDs). Phosphor crystals have been embedded into the glass substrates for the color-conversion function. The photoluminescence and photoluminescence excitation of the substrates have been studied in this work. The substrates can be used as color down-conversion substrates to realize WOLED.

 

The photometric characteristics of LEDs during their accelerated aging processes are explored extensively. One empirical model to describe the aging process of LEDs is proposed. Sixty LED chips are monitored on their normal operation to failure. Then, four aging characteristics of LEDs are found and analyzed.

 

In this paper, a spectral calculation method which can simply and directly evaluated by the weight of phosphor is developed to predict the spectral changing that the blue light emitting diode coated by the two-colors mixing phosphors.

 

The β-Ga2O3 thin films were grown on (001) LiGaO2 by hydride vapor phase epitaxy (HVPE). The effect of low temperature buffer layer on the growth of Ga2O3 film was investigated. The crystal orientation relationship is [001]LGO || [-201] β-Ga2O3, [100]LGO || [010] β-Ga2O3 and [010]LGO || [102] β-Ga2O3.

 

To provide a planar light source using laser-driven white light, a planar light guide design with remote phosphor layer is used in this study. The laser from LDs undergoes total internal reflection (TIR) and hits the remote phosphor on the planar light guide to generate the white light.

 

To realize the laser-based white light technology, the ring remote phosphor structure is used in this study. The inverted cone lens encapsulant in the structure directs the light from the blue laser diodes (LDs) to the surrounding phosphor layer, and reduces the high density laser irradiation on the phosphor layer.

 

The effect of annealing on AlN crystal grown by MOCVD is studied. It is found the annealing under the condition of 1180 C and pulsed NH3 flow can effectively improve surface morphology and lattice quality of AlN epilayer. Details of characterization will be provided.

 

OLEDs possess many outstanding characteristics, such as high efficiency, low power consumption, fast switching, and has evolved to the extent that commercial applications for cell-phones, televisions and lamps are available, photoluminescence, a powerful and breakless analysis technology, can reveal the band structure and the carrier transportation behaviors in a material.