1. Promising QD-OLED technology
Organic light-emitting diode (OLED) is a light source in which a thin layer of organic material placed between two conductors that can emit light of specific color by applying electrical current. To accelerate the commercialization of organic light-emitting diodes (OLEDs) have enhanced due to their capabilities as new generation displays and lighting sources. In comparison with other display technology, OLED displays are thin, efficient, flexible and transparent. In addition, they have better contrast, higher brightness, fuller viewing angle, a wider color range, much faster refresh rates and consuming lower power, thinner, very durable and also they can operate in a broader temperature range. But they have some disadvantages too. The cost of OLED displays is still too high. They have limited lifespan and suffer from permanent image retention. If these limitations can be overcome, OLED displays can find faster growth
In recent years, the display industry is rapidly interested in the world to combine
Researchers all around the world try to improve this field and they found that quantum dots (QDs) can be helpful. Excellent color-rendering properties and high luminous efficiency (LE) of OLED are obtained when the combination of colloidal QDs with light-emitting diodes (LEDs) was done. QD-LEDs are the important part of the next generation of solid-state lighting and display technologies due to their great color saturation features, tunable wavelength and narrow full-width at half-maximum (FWHM). Nevertheless many developments have recently been made in display and lighting board technology and this ability was specially developed to build a very thin flexible and transparent displays; scientists have found that using some extra thin layers between two conductors and choosing appropriate materials can be helpful for better performance of QD-LEDs [1, 2]. High brightness, flexibility, efficiency with long lifetime and low processing cost of QD-LEDs makes them different from LCDs, OLEDs and plasma displays.
QD-LEDs can produce dark blacks and whiter whites and create higher brightness than OLEDs. In addition, a wider and more true-to-life color palette will be possible in QD-LEDs than in OLEDs. Because, an improvement in operation lifetime of OLED devices can be achieved by using quantum dots. Finally yet importantly, QD-LEDs are cheaper than OLEDs. Nowadays, researches try to improve efficiency of passing light through the quantum dot crystals, which can help the QD-LEDs performance . QD-LEDs have some unique features such as better color accuracy, higher brightness, more stable performance and lower cost. Also, they are solution processable and suitable for wet processing techniques.
Li Z. Enhanced performance of quantum dots light-emitting diodes: The case of Al2O3 electron blocking layer. Vacuum. 2017; 137:38-41
Kang Y, et al. Quantum dots for wide color gamut displays from photoluminescence to electroluminescence. Nanoscale Research Letters. 2017; 12:154
Li Z, et al. Efficient and long-life green light-emitting diodes comprising tridentate thiol capped quantum dots. Laser & Photonics Reviews. 2017; 11:1600227