Cracking the Code: Unveiling the Secrets of Edge-Lit, Direct-Lit, and Full-Array TVs

Key Takeaways

LCD TVs can be grouped into three categories based on the type of LED backlighting system: direct-lit, edge-lit, and full-array.

LCD TVs equipped with local dimming technology have the ability to generate deep blacks and exhibit an improved contrast ratio. Among LCD TVs, Full-Array models are known to deliver the most exceptional contrast performance. On the other hand, OLED TVs utilize pixel-level local dimming, providing an almost boundless contrast ratio and being widely regarded as having superior picture quality. However, it is important to note that OLED TVs are often priced higher and may be susceptible to burn-in issues.

Modern LCD TVs rely on LED backlighting to generate the visuals you observe on the screen. However, their picture quality and cost can vary depending on the type of backlighting system they utilize. Consequently, let's delve into these backlighting systems and explore their distinguishing features.

LED Backlighting in LCD TVs

LCD TVs can be classified into three groups based on the type of LED backlighting system: Direct-lit, edge-lit, and full-array. Direct-lit TVs have LEDs positioned directly behind the display stack, while full-array TVs have a higher number of LEDs divided into different zones. In contrast, edge-lit TVs have LEDs placed on the perimeter, and their grouping into multiple zones may vary depending on the TV.

The presence of LED backlight zones in full-array and edge-lit TVs is crucial as it enables the implementation of a feature known as local dimming. This feature allows the TV to control the backlighting on a scene-by-scene basis. Consequently, the TV can turn off LED backlighting in areas requiring darkness while keeping other parts illuminated. As a result, LCD TVs with local dimming can produce rich, uniform blacks and have a superior contrast ratio compared to those without this feature.

Direct-Lit TVs

Direct lighting, the most recent addition to the backlighting methods in LCD TVs, made its emergence around 2012 as a derivative of the full-array TVs.

Direct-lit TVs are more cost-effective to manufacture compared to other types of TVs as they require fewer LEDs and do not require backlight control. Consequently, they are commonly found in the entry-level and mid-range sections of a TV manufacturer's offerings.

However, due to the reduced number of LEDs, these TVs necessitate being positioned at a greater distance from the screen to ensure adequate light coverage across the panel. Consequently, direct-lit TVs generally have a larger thickness in comparison to TVs equipped with alternative backlighting systems.

Edge-Lit TVs

Furthermore, the absence of backlight control greatly hampers the contrast ratio of direct-lit LCD televisions, as it is limited to the native contrast ratio of the panel. Consequently, direct-lit TVs employing VA-type LCD panels exhibit a respectable contrast ratio, while those utilizing IPS-type panels suffer from a subpar contrast ratio.

Edge LED backlighting was introduced in 2008 as a solution to making LCD TVs slimmer. Unlike other backlighting methods, edge-lit TVs have LEDs placed on the edge of the screen. To ensure uniform lighting, a diffuser is required, which adds to the cost of these TVs, making them slightly more expensive than direct-lit TVs. However, the price of an LCD TV consists of more than just the cost of backlighting, so you can find both affordable and expensive edge-lit TVs in the market.

Some edge-lit TVs offer local dimming support, but they typically have fewer backlight zones compared to full-array TVs. In edge-lit local dimming, individual LEDs illuminate entire columns of the screen, resulting in less precision and minimal improvement in contrast ratio.

Full-Array TVs

Hannah Stryker  

Full-array televisions excel in their backlight implementation compared to LCD televisions. These TVs boast a significant quantity of LEDs, which are further divided into several zones for dynamic backlight control. Consequently, the number of backlight zones and the local dimming technique contribute to enhancing the native contrast ratio of the LCD panel, resulting in a notable improvement ranging from modest to excellent. The augmentation is further amplified with the increased LED density, evident in the successive generations of "mini-LED" TVs.

Consequently, full-array TVs are renowned for their ability to deliver deep blacks and vibrant highlights, making them an exceptional choice for showcasing HDR content.

Unfortunately, LCD TVs equipped with full-array local dimming may experience different screen artifacts, including blooming and black crush. The occurrence of these issues depends on factors such as the number of backlight zones and the overall implementation of local dimming.

Edge-Lit Vs. Direct-Lit TV: Which Is Better?

In general, edge-lit TVs offer superior visual quality compared to direct-lit TVs, making them a preferable choice for those who prioritize visual fidelity. It is worth noting that the majority of mid-range television sets available for purchase, both online and in stores, are edge-lit. However, it is advisable to verify this information before finalizing your purchase.

There are two specific scenarios in which a direct-lit TV may be more suitable than an edge-lit TV:

You want an enormous TV for as little money as possible

You simply want a cheap TV

Edge-lit TVs, being the more premium technology, tend to be pricier than direct-lit TVs of the same size. This is why most of the large, affordable 4K displays available for sale are direct-lit, as are the majority of smaller, inexpensive TVs. This is actually advantageous since not every situation requires the slight benefits offered by edge-lit displays. It is a good opportunity to save money.

As mentioned earlier, variations in quality among models and manufacturers can complicate comparisons. A well-designed direct-lit TV is likely to have a significantly better appearance than a poorly designed edge-lit display, but it's impossible to predict for sure in advance.

How to Check the Backlighting System of a TV

When shopping for a new TV and wanting to learn about its backlighting system, you can refer to the TV's specifications. Typically, manufacturers indicate whether an LCD TV is direct lit, edge lit, or full array. Additionally, for full-array TVs, the specifications also include information about the number of local dimming or backlight control zones. This number may vary based on the size of the TV, and it can affect the level of contrast ratio improvement you can anticipate.

TV reviews from reputed websites such as Rtings.com also mention these details.

What About OLED TVs?

Josh Hendrickson

Unlike LCD TVs, OLED TVs do not require a backlight as they are self-emissive. Each individual pixel of an OLED panel has the capability to generate and turn off its own light, resulting in the display of a perfect black color. Consequently, OLED TVs provide pixel-level local dimming, leading to an incredibly high contrast ratio and widely acknowledged superior picture quality. However, it is important to note that OLED TVs are typically pricier than LCD TVs and may be susceptible to burn-in issues.

Backlighting Matters

The backlight system of an LCD TV has a significant impact on its picture performance. For those seeking the best picture quality when shopping for a new TV, full-array TVs are generally the top choice. However, if budget constraints are a concern, direct and edge-lit TVs can still provide good visual performance. It is advisable to read expert reviews to gain a better understanding of the overall quality of a specific television. Whenever possible, it is recommended to see the television in person at a store since ultimately, it will be your personal television, and no amount of technical analysis or review reading can surpass the direct answer to the most crucial question: Does it look good to you?