A mini-LED display pertains to a specific backlighting scheme used in panels based on LED-backlit LCD technology. It involves using small-sized light-emitting diodes to illuminate LCD panels, improve local dimming capabilities, and increase the contrast ratio of an equipped display panel.
Pros of Mini-LED: Advantages and Applications
1. Has the Advantages of the Overall LED-Backlit LCD Technology
An LCD is a photo-emissive display technology. It does not light by itself and needs illumination or backlighting to make images visible. This is in contrast with electro-emissive display technologies based on light-emitting diodes such as OLED or AMOLED.
The preferred backlight for the majority of LCD monitors back then was a cold-cathode fluorescent lamp or CCFL. This changed beginning in 2010 when manufacturers and market trends shifted to LED-backlit LCD. LED is more energy efficient with 20 to 30 percent lower power consumption, has a broader color gamut, and enables high-speed switching.
Mini-LED inherits the aforementioned advantages or benefits. It is an upgrade to the overall LED-backlit LCD technology and has improved existing LCD technologies such as virtual alignment or VA LCD and in-plane switching or IPS LCD.
2. Improved Contrast Ratio to Match OLED Display Technology
One of the key advantages of OLED displays over IPS LCD panels is a higher contrast ratio. OLEDs produce natural and deeper blacks. Most LCDs tend to generate mere darker shades of grey. High-end LCDs such as the IPS Retina Display from Apple can produce considerable deep blacks but still pale in comparison to OLED display panels and screens.
Traditional LED-backlit LCDs have limited local dimming capabilities. Black-colored images are displayed on the screen by turning off backlighting on a specified area within the panel. Traditional LED-backlit application uses multiple but sizable strips or areas of LED backlighting. This results in light bleeding out from other areas.
Mini-LED addresses this issue by increasing the local dimming capabilities of LCD panels. The concept behind using small-sized LEDs is to emulate the electro-emissive nature of OLED. Note that OLED can produce deep blacks since it does not need backlighting, and black-colored images are produced by turning off individual organic light-emitting diodes.
An LCD that employs mini-LED technology essentially uses LEDs about the size of 0.9 to 0.1 millimeters for backlighting. These individual LEDs can be turned on and off to enable more targeted dimming and allow the production of deeper blacks and better contrast ratio This translates to superior image quality that could rival OLED displays.
3. Cost-Effective Alternative Over MicroLED Display Technology
Take note that mini-LED is different from MicroLED. The former is a backlighting scheme used in LED-backlit LCD panels and the latter is an actual electro-emissive display technology similar to OLED displays that uses small-sized light-emitting diodes.
One key advantage of using mini-LED as a backlighting scheme for LCD is cost. It is more practical and economical to produce LCD with mini-LED than to produce OLED and MicroLED. Furthermore, when applied in an IPS LCD, a mini-LED LCD inherits the advantages of in-plane switching over OLEDs such as include longer lifespan and durability.
An IPS LCD panel that uses mini-LED as backlighting can provide superior image quality that can rival OLED and MicroLED. It can produce deeper blacks and a higher contrast ratio while also offering brightness that can exceed electro-emissive display technologies.
Cons of Mini-LED: Disadvantages and Limitations
1. Still More Expensive Than Traditional LED-Backlit LCD
A notable disadvantage of mini-LED is that it is still about 20 percent more expensive to manufacture than conventional LED-backlit LCD. Take note that a 45-inch to 65-inch LCD panel will need about 14000 to 20000 small-sized LEDs as its backlighting.
The technology is also relatively new. It also requires more sophisticated components and complex manufacturing processes. The manufacturing capabilities of suppliers need to keep up with the demand. The potential higher demand for micro-LED IPS LCD panels will definitely consume the production capacity of LED chip manufacturers.
Hence, because of its more expensive manufacturing cost and limited production capacity of manufacturers, the technology is best reserved for top-tier devices such as premium smartphones and tablet computers, as well as high-range laptops and television sets.
2. Notable Limitations and Issues Compared to OLED Display
It is true that mini-LED improves the quality of an LCD panel or screen. However, when compared side-by-side to an OLED, it has noticeable limitations and issues. The black levels and overall contrast ratio of displays using this backlighting scheme are not comparable to OLED because they can produce blooming and halo effects in very dark scenes.
Another disadvantage of mini-LED is that it can have narrower viewing angles than traditional LED backlighting. A narrow viewing angle can result in color shifts or lower brightness and contrast at certain angles. This drawback comes from the fact that the minuscule light-emitting diodes are packed closer together. OLED still has the best viewing angle.
It is also worth mentioning that this backlighting scheme is still not feasible for very large displays. This is because the miniscule light-emitting diodes are more difficult and costlier to manufacture and assemble at larger scales. The price of a particular end-use display based on this backlighting scheme would increase drastically with an increase in its size.
The pervasiveness of LCD based on mini-LED is still limited. Manufacturers such as Samsung and LG Electronics still prefer using OLED technology for smartphones and high-end television sets. IPS LCD and VA LCD that use conventional LED backlighting are also the preferred LCD technologies for mid-range display panels because of their lower costs.
3. Mini-LED Also Inherits the Drawbacks of LCD Technologies
Furthermore, depending on its application, mini-LED also inherits the disadvantages of the underlying display technology. Consider in-plane switching LCD as an example. An IPS LCD also has a slower refresh rate and pixel response than OLED by default.
An IPS LCD also consumes more power than OLED and other electro-emissive display technologies because it uses backlighting. This makes them impractical for low-powered and battery-operation applications. It is still worth noting that micro-LED can improve the energy efficiency of LCD panels because of its better local dimming capabilities.
This backlighting scheme might be unsuitable for other LCD technologies such as TN LCD and VA LCD because it might drive up their manufacturing cost. Take note that TN LCD is the most preferred option for low-cost affordable LCD panels and screens.
Quick Rundown: Pros and Cons of Mini-LED
The following are the advantages of Mini-LED:
- Improves the capabilities and applications of LED-backlit LCD technologies when compared to other backlighting schemes.
- Can rival the deep blacks or high contrast ratios of OLED and MicroLED displays while offering superior brightness and outdoor visibility.
- It is a cost-effective alternative to MicroLED display technology. A Mini-LED IPS LCD can rival both OLEDs and MicroLEDs minus cost.
The following are the disadvantages of Mini-LED:
- It is more expensive to manufacture than traditional LED-backlit LCD panels and this limits its applications to top-tier and high-range devices.
- Manufacturers of LED chips need to increase their production capacity and capabilities to keep up with upcoming demands.
- It can inherit the disadvantages of the underlying LCD technology. Take note that IPS, TN, and VA LCD technologies have their respective drawbacks.
FURTHER READINGS AND REFERENCES
- Horn, R-H., Chien, H-Y., Trantair, F-G., and Wuu, D-S. 2018. “Fabrication and Study on Red Light Micro-LED Displays.” IEEE Journal of the Electron Devices Society. 6: 1064-1069. DOI: 1109/jeds.2018.2864543
- Huang, Y., Hsiang, E-L., Deng, M-Y., and Wu, S-T. 2020. “Mini-LED, Micro-LED, and OLED Displays: Present Status and Future Perspectives.” Light: Science & Applications. 9: 105. DOI: 1038/s41377-020-0341-9
- Konsyse. 2020. “Difference Between Micro-LED and miniLED.” Konsyse. Available online
- Moore, S. K. 2019. “microLED Displays Expected in 2020: The Last Remaining Hurdle is Mastering Mass Production.” IEEE Spectrum. 56(8): 8-9. DOI: 10.1109/MSPEC.2019.8784111