Mini LED Backlight

Definition and Technical Principles

Mini LED backlighting refers to the technical solution of using miniature light-emitting diode chips measuring 100 to 200 micrometres as the backlight source for liquid crystal display (LCD) screens. Its core feature lies in upgrading conventional LED backlighting from mere dozens of diodes to a high-density Mini LED array comprising hundreds or even thousands of individual diodes.

Compared with conventional LCD backlighting, the primary technical advantage of Mini LED technology is Local Dimming—where the system partitions the backlight panel into hundreds or thousands of independently controlled zones, dynamically fine-tuning the brightness according to on-screen content. When rendering black scenes, the Mini LEDs in the corresponding zones can be switched off completely, dramatically boosting contrast ratios to rival OLED display performance. For instance, Tianma's 15.6-inch slim Mini LED display achieves an ultra-high contrast ratio of 600,000:1 alongside 100% ultra-wide colour gamut coverage.

Automotive Application Status and Industry Landscape

Mini LED backlighting is fast emerging as the mainstream display technology for premium smart cockpits. Between 2022 and 2025, carmakers such as NIO, Li Auto, BYD, XPeng, Geely, GM, and Ford have progressively adopted automotive Mini LED display solutions. In 2026, international marques including Mercedes-Benz, BMW, and Hyundai-Kia are also set to accelerate their adoption.

In terms of series production, the standard 48-inch Skyline digital display on NIO's all-new flagship SUV, the ES9, features a bespoke Mini LED COB backlight solution engineered by Refond, delivering a million-to-one contrast ratio and 5K resolution. The GWM WEY V9X comes standard across all variants with dual 17.3-inch connected Mini LED screens, supporting over a thousand local dimming zones and DCI-P3 wide colour gamut coverage. The Land Rover-Chery joint brand Freelander 8 is equipped with a 15.6-inch Mini LED central touchscreen featuring 2,304 independent local dimming zones.

On the supplier front, Refond is a key player in the automotive Mini LED backlighting sector, having supplied custom backlight setups for models including the NIO ES9, WEY V9X, and Audi Smart Island. Tianma, meanwhile, spearheaded the formulation of China's first automotive Mini LED display industry group standard.

Technical Advantages and Limitations

Compared to OLED, Mini LED backlighting delivers three distinct advantages for large-format in-car displays: superior peak brightness (with select solutions achieving up to 3,000 nits); a longer operating lifespan free from burn-in risks; and enhanced cost competitiveness supported by an established, mature LCD supply chain. On the performance front, Hivi's 16-inch RGB Mini LED setup utilises red, green, and blue chips to directly emit primary colours, eliminating secondary colour conversion stages to achieve over 130% NTSC colour gamut coverage and a 1,000,000:1 contrast ratio. In terms of cabin integration, the 2.43-inch Mini COB white-light touchscreen on the Audi E5 Sportback's centre armrest "Audi Smart Island" offers precise local dimming and 1,000 nits of high brightness, supporting more than 50 quick-access functions.

The primary limitation of current Mini LED technology lies in scalability: increasing the number of dimming zones substantially raises the complexity of driver ICs and control systems, driving up processing power requirements and overall costs. Furthermore, owing to inherent architectural constraints, Mini LED backlighting remains unable to directly rival OLED in terms of ultra-slim profiles and flexible form factors.