Effects of spectral parameters on the light properties of red-green-blue white light-emitting diodes

Abstract

Red-green-blue white light-emitting diodes (RGB-WLEDs) have great potential as commercial solid-state lighting devices, as well as visible light communication because of their high color-rendering index (CRI) and high response frequency. The quality of light of an RGB-WLED strongly depends on its spectral parameters. In this study, we fabricated RGB-WLEDs with red, blue, and green LEDs and measured the spectral power distribution (SPD). The experimental SPD is consistent with the calculated spectrum. We also measured the SPDs of LEDs with different peak wavelengths and extracted the spectral parameters, which were then used for modeling. We studied the effect of the wavelength and the full width at half-maximum (FWHM) on both the color rendering index and the luminous efficiency (LE) of the RGB-WLED using simulations. We find that the LE improves as the wavelength of the blue LED increases and the wavelength of the red LED decreases. When the wavelength of the green LED increases, the LE increases first, but later decreases. The CRI of the RGB-WLED increases with the wavelengths of the red, blue, and green LEDs first, but then decreases. The optimal wavelengths and FWHMs for maximum color-rendering and LE of the blue, green, and red LEDs are 466, 536, 606 nm; and 26.0, 34.0, and 19.5 nm, respectively.

High Emission Quantum Yield Tb3+‐Activated Organic‐Inorganic Hybrids for UV‐Down‐Shifting Green Light‐Emitting Diodes

“…The prospects for using tU5Tb as a pcWLED can be further evaluated by comparing its optical parameters to a published simulation [28] where a WLED is made by using RGB components and the ideal characteristics for each RGB component are calculated in order to maximize CRI and LE. Here, it is reported that for a target CRI of 85 and 180 lm W -1 an ideal green would have a dominant wavelength of ≈ 536 nm with FWHM of 34 nm.…”

Preparation and photoluminescence study of Alumin o-boro silicate YAG fluorescent glass for White LED

“…Optical parameter of white LEDs will change after a period time of using as the light-emitting chip and phosphors have different life span; additionally, when the phosphor is heated by LED chips, it will accelerate phosphor deterioration, luminousness of organic encapsulating material also will decline, making the life span of white LED decrease [3,4,5]. Although RGB LED chips of white LED have relatively wide and low color temperature range, it can easily achieve high color rendering index, but the RGB chips have different light attenuation coe cient, it needs to add appropriate control circuit [1,6,7].…”

Luminous and Melanopic Efficiency Performance of Phosphor-Converted LEDs with Tunable Spectral Characteristics

“…Tunable spectral characteristics of LEDs lead to tunable performance. Color rendering properties and luminous efficacy vary with the peak wavelengths and FWHMs of the spectra, both in a chip-emitting and a phosphor-converted LED (PC LED) [1,[6][7][8]. Researchers have put forward trade-off strategies by boosting the LER with high color rendering properties [9,10], whereas the study of melatonin suppression has revealed the impacts of spectral composition on human circadian rhythms [11][12][13], suggesting the inadequacy of traditional assessments of luminous efficacy and color rendering.…”