Full Array Local Dimming (FALD) is an advanced backlighting technology used in LED televisions to enhance contrast and improve picture quality by controlling the brightness of individual zones across the screen. This technology is a significant improvement over traditional edge-lit LED displays, where the light source is positioned along the edges of the screen, and the entire backlight is uniformly lit, limiting contrast and black level performance.

Understanding the Basics of LED Backlighting

To understand Full Array Local Dimming, it’s essential to first grasp the basics of how LED TVs work. LED (Light-Emitting Diode) TVs are a type of LCD (Liquid Crystal Display) TV that uses LEDs as the light source to illuminate the pixels of the display. The LEDs are responsible for providing the brightness that passes through the LCD panel, which modulates this light to create the images you see on the screen.

In traditional LED TVs, the backlighting can be of two main types: edge-lit and direct-lit.

  • Edge-lit TVs have LEDs placed along the edges of the screen, and light is diffused across the screen using a light guide panel. While this allows for thinner displays, it often results in uneven lighting and poorer contrast, especially in darker scenes.
  • Direct-lit TVs have LEDs placed directly behind the screen but without the ability to dim specific areas. This setup provides better overall brightness, but still struggles with achieving deep blacks and high contrast ratios.

What is Full Array Local Dimming?

Full Array Local Dimming takes the direct-lit concept further by arranging the LEDs in a full grid or array behind the entire screen. This grid is divided into multiple zones, each of which can be individually controlled. This means that the brightness of each zone can be adjusted independently based on the content being displayed, allowing the TV to dim or brighten specific parts of the screen without affecting others.

For example, in a scene with both bright and dark areas (such as a starry night sky), a FALD-equipped TV can dim the zones where the black sky is displayed while keeping the zones with stars or other bright objects fully illuminated. This results in much deeper blacks, reduced light bleed, and a higher overall contrast ratio compared to edge-lit or standard direct-lit LED TVs.

Benefits of Full Array Local Dimming

  1. Enhanced Contrast and Black Levels: The primary benefit is the significant improvement in contrast. By precisely controlling the light output of individual zones, it allows for darker darks and brighter brights. This results in richer, more dynamic images, especially in scenes with high contrast between light and dark areas.
  2. Reduced Halo Effect: In TVs without local dimming, bright objects on a dark background often produce a “halo” or blooming effect, where light from the bright areas spills into the dark areas. FALD minimizes this effect by controlling the illumination more precisely, ensuring that bright objects remain sharp and defined against dark backgrounds.
  3. Better Uniformity: Compared to edge-lit models, FALD TVs generally offer better screen uniformity. The light is more evenly distributed across the entire screen, reducing issues like bright spots or clouding that can occur with less sophisticated backlighting techniques.
  4. Improved HDR Performance: High Dynamic Range (HDR) content benefits greatly from this technology. HDR relies on the display’s ability to show a wide range of brightness levels, and FALD enhances this capability by delivering deeper blacks and brighter highlights, making HDR content look more vivid and true to life.

Limitations and Considerations

While Full Array Local Dimming offers many advantages, it’s important to be aware of its limitations:

  1. Number of Dimming Zones: The effectiveness depends on the number of dimming zones. TVs with more dimming zones can control the backlight more precisely, leading to better performance. However, even the best FALD TVs may exhibit some blooming or halo effects, particularly in scenes with extreme contrast, though much less than in non-FALD models.
  2. Cost: FALD technology is pricier to produce than edge-lit or standard direct-lit backlighting, making FALD-equipped TVs generally more expensive. However, prices have been coming down as the technology becomes more widespread.
  3. Thickness: FALD TVs tend to be thicker than edge-lit models because they require space for the array of LEDs and the necessary cooling and control systems.
  4. Energy Consumption: FALD TVs can consume more power than other LED TV types due to the need to power a larger number of LEDs and the additional processing required to manage local dimming zones.

Comparison with Other Technologies

When compared to OLED (Organic Light-Emitting Diode) TVs, which offer per-pixel lighting control (each pixel emits its light), FALD still falls short in terms of contrast and black level performance. OLEDs can achieve true blacks since individual pixels can be turned off completely, something FALD cannot match due to its reliance on backlighting. However, it’s a significant improvement over standard LED technologies and is often more affordable than OLED, making it an excellent option for those seeking high-quality picture performance without the higher cost of OLEDs.

FALD is also better than Edge-lit Local Dimming systems, which only adjust brightness along the edges of the screen, leading to less precise control and more noticeable blooming.

Conclusion

Full Array Local Dimming represents a substantial advancement in LED TV technology, offering significant improvements in contrast, black levels, and overall picture quality compared to traditional edge-lit and direct-lit displays. By dividing the backlight into independently controllable zones, FALD allows for more precise illumination, enhancing the viewing experience, especially for HDR content. While it may not match the absolute black levels of OLED technology, FALD provides a compelling alternative for those seeking exceptional picture quality at a relatively lower price point. As TV technology continues to evolve, Full Array Local Dimming remains a key feature in delivering high-quality visual experiences.