Solar spectrum matching with white OLED and monochromatic LEDs

Abstract

In this paper, the solar spectrum matching in the visible range of 380-780 nm with white organic light-emitting diode (OLED) and monochromatic light-emitting diodes (LEDs) is investigated. The correlation index () is used to evaluate the difference between the matching spectrum and the solar spectrum. The optimal combination is obtained by the least squares method. We also perform subtraction experiments to find the optimal combination. We utilize a common white OLED device design and just change the species of monochromatic LEDs used. We report and evaluate different degrees of matching effects. The results show that the correlation index of the best combination can reach 94.09% with white OLED and 36 monochromatic LEDs. We define three levels of performance as an evaluation system in accordance with the matching effect. The level is excellent with an above 90.14%. The good level is from 86.65% to 58.28%. From 42.08% to 33.06% is the reasonable level. Compared with other methods, using white OLED combined with monochromatic LEDs achieves the best solar spectrum matching effect. The results can be applied to different requirements of engineering practice.

Theoretical Study on Thermally Activated Delayed Fluorescence Emitters in White Organic Light-Emitting Diodes: Emission Mechanism and Molecular Design

“…33,35,36 Different from that in S 1 or T 1 , particles and holes are mainly distributed in the acceptor for T 2 of PTZ-BP-eq and FCO-CzS-eq; thus, the T 2 states have a typical LE characteristic. 3 LE usually leads to a stable triplet state; thus, a large SOC value can be obtained, enhancing the RISC rate from 3 LE to 1 CT. 33,34,37 It is also consistent with the small ΔE ST values calculated for quasiequatorial conformations. The thermal activation delay fluorescence with long wavelengths should be contributed by the quasi-equatorial conformations.…”

“…White organic light-emitting diodes (WOLEDs) are of increasing interest owing to their great potential in display devices, solid-state lighting systems, and molecular sensors. , The typical method for the generation of WOLEDs is based on the two complementary (blue and orange) or three primary (blue, green, and red) color emitters, covering the whole visible light range from 380 to 780 nm, which makes most WOLEDs have complex and precise multilayer device structure characteristics accompanied by huge cost and an intricate process. − Developing an emitter that displays white light can handle this problem, and most of them are achieved using excited-state intramolecular proton transfer (ESIPT), monomer-excimer emission, fluorescence resonance energy transfer (FRET), and fluorescence/room-temperature phosphorescence (RTP) systems; or vibration-induced emission (VIE) plus aggregation-induced emission (AIE); etc. At present, single-component white light emitters with dual-emission characteristics are an exciting and huge challenge due to their more simplified manufacturing process and superior color stability.…”

Using CaCO3-doped package to improve correlated color temperature uniformity of white light-emitting diodes

“…The purpose of this part is to demonstrate the computing procedure to determine resultant optical properties. The mathematical models applied in the computing procedure are developed based on Mie-theory and Monte Carlo method because these scientific theories are the functioning core of optical engineering programs such as Lighttools, Tracepro, and ASAP [23]- [26]. It is more reliable and even possible to acquire an improvement in structure and simulation process when using these modified mathematical models to calculate the optical properties of lighting configuration.…”

Investigation of MAl2−xSixO4−xNx:Eu2+ phosphor for improving luminescence properties of white LEDs

“…However, we can only customize the excitation as well as absorptivity lines within the ultraviolet limit. Consequently, such materials must undergo stimulation within the UV zone (e.g., less than 350 nm) in order to emit efficiently [14]- [16]. As a result, the excitation bands of Eu 2+ -doped MAl2O4 (M = Ca, Sr, Ba) are inconsistent with the UV blue discharge between 370 and 460 nm created by InGaN-based light-emitted diodes (LED) devices in generating white illumination.…”