Wide-Range Correlated Color Temperature Light Generation From Resonant Cavity Hybrid Quantum Dot Light-Emitting Diodes

Abstract

Abstract-This study presents extremely uniform colloidal quantum dot white light-emitting diodes (QD-WLEDs) that demonstrate a high color rendering index (CRI) and correlated color temperatures (CCTs) ranging from 2500 to 4500 K. Experimental results indicate that the structure of the distributed Bragg reflector (DBR) containing a stopband in the UV region enhances the intensity output of both monochromatic QD-LEDs and QD-WLEDs by reflecting the unconverted UV light back onto the package to excite the QDs further. Furthermore, the angular CCT uniformity of the QD-WLEDs also improved considerably because of the dependence of the DBR structure on the incident angle. The angular CCT deviation in the range of -70°to 70°de-creased to 39 K and the CRI of the WLED is higher than 90. The high-CRI and uniform angular CCT QD-WLED containing the DBR demonstrates potential applicability as the lighting source of next-generation display devices and solid-state lighting.

Advances in Quantum-Dot-Based Displays

“…Hence, they are frequently referred to as artificial atoms [1][2][3]. Because of their distinctive properties, QDs have found applications in a variety of modern day technologies including solar cells [4][5][6][7][8], photodetectors [9], photodiodes [10], field-effect transistors [11], biological systems [12][13][14][15], and light-emitting diodes [16][17][18].…”

Liquid Type Nontoxic Photoluminescent Nanomaterials for High Color Quality White-Light-Emitting Diode

“…4c. For the fabrication of the dispensing package, the conventional dispensing QD LEDs process was applied [34, 39]. In case of dispensing QD package approach, firstly we mixed the PMMA and QDs to produce the solidified structure in the LED package.…”

“…The P-Si nanocrystals can exhibit long-wavelength emissions to compensate for the absence of long-wavelength bands in the GQD emission spectra, and thus can yield warm white light. As per literature survey, L. T. Canham’s group contributed substantially to investigations of mesoporous Si layers with high porosity for visible (red) photoluminescence at room temperature [34]. The fabrication of P-Si QDs can be categorized into two approaches, bottom-up and top-down, similar to GQD fabrication processes.…”

“…This study selects a top-down approach to fabricate the P-Si QDs because it is suitable for mass production. Finally, these two types of device structures neutral white and warm white LEDs were fabricated by using dispensing and liquid-type package processes were exhibited excellent color rendering index (CRI) and luminous efficiency values and also produces [34–36].…”

Effect of Red Y2O3:Eu3+ phosphor on the color quality and luminous efficacy of the 7000K IPW-LEDs

“…On another way, the LO of the W_LEDs can be improved significantly by co-doping the green Ce0.67 Tb0.33 MgAl11 O19: Ce, Tb phosphor to the phosphor compounding as shown in [4]. For the purpose of improving the CRI of the W-LEDs, authors in [5,6] proposed to mix the red phosphors to the high CRI multi-chip W-LEDs [7] used green (Ba, Sr) 2SiO4: Eu2+ and red CaAlSiN3: Eu2+ phosphors with various packages W-LEDs to enhance the CRI and [8] showed the missing red component in phosphor-converted W-LEDs for improving its optical properties.…”