Buying a new TV can be downright overwhelming these days. From 4K to 8K resolution, OLED to QLED, HDMI 2.1 to variable refresh rate – the jargon just doesn‘t stop. But behind all those advanced features, one of the most important choices is actually the TV‘s backlight system. This is what produces the image you see by shining light through each tiny pixel.
There are two main backlight arrangements used in today‘s LED TVs: edge-lit and full array. You‘ll see these terms thrown around constantly. But what do they actually mean? And which gives you better contrast with deep blacks and bright highlights?
In this guide, we‘ll break down the key differences between edge-lit vs full array backlighting so you can decide what‘s more important for your next TV purchase. I‘ll translate the geek speak into simple advice tailored to your viewing needs – no PhD required!
The terms "edge-lit" and "full array" describe where the LEDs are placed behind the TV screen to produce the backlight:
What is Edge-Lit Backlighting?
With edge-lit backlights, rows of LED lights are positioned along the edges of the display, either top & bottom or entirely around the perimeter.
A light guide panel sits behind the LCD layer to evenly spread this light across the screen:
Edge lighting allows exceptionally thin display panels, since no LEDs have to fit behind the screen itself. This is why edge-based TVs often focus on sleek, minimalist aesthetics. Samsung‘s popular The Frame lifestyle TV uses edge lighting to mimic the slim form of wall art framing when mounted.
By independently dimming the top & bottom LED zones, edge lit screens can also achieve basic local dimming. However, there are typically less than 20 zones to work with.
What is Full Array Backlighting?
In a full array backlight system, rows of LEDs are placed across the entire rear of the TV panel instead of just the edges. This allows for more granular regional control of backlight brightness:
With LEDs spread evenly behind the display, TV manufacturers can coordinate the output of hundreds to thousands of zones to match the video content. This is known as local dimming – when bright objects appear on screen, LEDs zones behind those areas increase intensity. Dark shadows prompt nearby zones to dim down.
Full array LED TVs essentially have a dynamic array of LED "spotlights" fine-tuning illumination based on what‘s on screen. This can optimize contrast scene-by-scene for a more realistic and natural picture compared to simpler edge-based screens.
Next let‘s examine how this arrangement directly impacts contrast performance…
Contrast is what gives displayed images a true sense of depth and realism. This crucial metric indicates how well a television can produce deep, dark shadows alongside bright, intense highlights in the same scene.
There are several key performance criteria we can examine to determine contrast capabilities:
Black Level Performance
Black level indicates how truly dark a display can render shadows and black tones without fading into gray. Think dark suits against a black limo door under nighttime city lights.
Full array backlighting enables impressively deep, nuanced blacks thanks to the fine-grained local dimming control from up to thousands of zones. Areas displaying black can selectively dim LEDs down to near inky levels.
By comparison, edge-lit panels struggle to achieve the same level of adjustment with less than 20 dimming areas. Shadow detail is often washed out as zones fail to effectively lower light output.
According to television review site Rtings.com testing, leading full array TVs can produce a 0.01-0.02 cd/m2 black level compared to 0.07-0.15 cd/m2 range for edge-lit models – over 7X darker!
Peak Brightness
While mastering black level is crucial, ideal contrast also requires vibrant, eye-catching highlights. Peak brightness measures a display‘s maximum white luminance when viewing highlight details.
Here full array LCD TVs again outpace edge-lit models, with some sets reaching upwards of 2000 nits peak brightness based on real scene measurement. That‘s over 4X stronger than a typical edge-lit screen.
These lighter elements seem to leap off the screen with vivid intensity. Just don‘t forget your sunglasses!
Contrast Ratio
By factoring black level and peak brightness capabilities together, we can calculate an overall native contrast ratio:
Based on these luminance figures, full array TVs can achieve anywhere from 3000:1 to an incredible 8000:1 contrast ratio. Leading edge-lit screens still remain limited to 3000-4000:1 at best.
Ultimately, that massive differential in light output control leads to punchier, more true-to-life contrast across both bright and dark content with full array backlighting.
Dimming Zones
You‘ll also see the concept of "dimming zones" used constantly when discussing local dimming quality. This simply refers to the number of independently controlled LED zones that can adapt intensity based on screen content.
Think of it as display "resolution" – the more discrete backlighting areas available, the more precise contrast can be rendered. Leading edge-lit TVs might have around 16 zones. Mid-range full array models start at about 30 zones, scaling up to several hundred zones or more on premium sets.
Mini-LED and QD-OLED technology now enable over 5,000+ zones for essentially pixel-level precision! But you‘ll pay dearly for that cutting-edge performance.
Even with only 100-200 zones, full array LED TVs still achieve outstanding contrast control and shadow detail compared to edge lighting. Shop smartly based on your budget!
How do these lab measurements actually impact real-world image quality though? Let‘s examine some edge-lit and full array TV models side-by-side:
Entry-Level Edge Lit – TCL 4 Series
TCL‘s budget-friendly 4 Series Roku TVs promise big screens at very wallet-friendly prices. But many visual compromises are made to achieve that discount pricing.
The 4 Series utilizes basic 60Hz LED edge lighting with just 8 dimming zones. Performance is serviceable in brighter rooms but quite disappointing in home theater settings.
Blacks appear more washed out gray with noticeable blooming and flashing artifacts. HDR content fails to deliver the specular punch and refined shadow detailing the format promises.
You‘re better off saving up your pennies for a model with robust full array dimming…
Mid-Range Edge Lit – Samsung Q60B QLED
As we move up the price curve, Samsung‘s popular mid-range Q60B QLED TV delivers markedly better picture quality thanks to quantum dot enhancement. Vibrant colors and solid HD/SDR content playback improve the experience.
But with edge-based lighting and only around 16 zones, the Q60B still exhibits black level blooming and blown-out highlights in challenging HDR content. Dark scene detail is lost and dimly lit games lack atmosphere.
While fine for brightly-lit rooms, the Q60B fails to impress discerning viewers looking for that cinema-like contrast.
High-End Full Array – Sony X95K LED
On the other hand, Sony‘s flagship X95K 4K LED TV shows the full potential of precision full array backlighting.
Over 200 independent LED zones enable near pixel-level local dimming, inky blacks, and up to 2000 nits peak brightness for dazzling HDR specular highlights. Even the most challenging content across movies, sports, games, and streaming remains richly detailed with superior contrast.
Of course that cutting-edge performance commands a premium price tag. But discerning home theater enthusiasts need not settle for anything less.
Based on extensive technical evaluation and real-world testing, there‘s no debate here – full array local dimming delivers vastly better contrast performance compared to edge-lit LED displays.
The ability to finely tune hundreds or thousands of LED zones provides LCD televisions the horsepower needed to achieve inky, detail-rich blacks right next to piercing bright highlights.
Meanwhile edge lighting struggles with backlight consistency across large screen sizes. Blooming, flashing, and black detail loss remain persistent issues current edge dimming technology cannot overcome.
Yes full array TVs carry a higher starting price. But even budget models with just 100+ zones provide exponential contrast gains over edge-lit screens – critical for discerning viewers that enjoy movie nights in dedicated home theaters and living room entertainment spaces.
With all that in mind, let‘s distill things down to simpler backlight recommendations based on common viewing profiles:
The Budget Buyer
If cash is tight but you still desire the maximum possible contrast your limited dollars can buy, full array is again the way to go.
Entry-level models like the Hisense U7HF still include 120+ dimming zones. While not as adept at handling intense HDR, performance in darker rooms surpasses any edge-lit option at this price point.
The Casual Streamer
Prefer binging Netflix hits and Youtube highlight reels over critical film analysis? Edge-lit TVs strike an affordable sweet spot, though still limit contrast compared to full array options.
For vibrant color and solid HD streaming, the Hisense U6 series balances sleek style with great smart features.
The Sports & Gaming Enthusiast
Fast on-screen motion clarity is essential for keeping up with balls flying across fields or first person shooter gameplay. That makes higher refresh rates and dimming zone counts equally vital!
Mid-range full array picks like the TCL R646 handle fast motion with ease while providing punchy contrast that won‘t get lost in darkly-lit in-game environments.
The Home Theater Lover
Critical viewers wanting a truly cinematic experience with inky blacks, vibrant color, and searing peak brightness have only one choice: premium full array LED or better.
Flagship mini-LED and QD-OLED models from LG, Samsung and Sony offer the pinnacle in LED-LCD contrast performance and future-proof your investment as 4K HDR content continues expanding.
Evaluating a TV‘s backlight system may not be as flashy as pixel counts or SmartHub operating systems. But it remains one of the most crucial elements for achieving captivating image realism on par with a darkened cinema.
While edge-lit LED televisions retain popularity thanks to svelte form factors and budget price tags, discerning viewers needing more refined contrast ought to set their sights on full array. Only localized backlights can achieve the level of intelligent dimming required for an immersive viewing experience full of dynamic highlights and deep, detailed shadows.
So don‘t merely satisfy yourself with the status quo – let full array opening up your viewing to a whole new level of light and darkness! Your eyes will thank you for taking contrast more seriously.
I hope this guide helps cut through the overly complex backlight jargon to highlight what really matters most for your next TV purchase. Let me know if you have any other questions arise during your display research! I‘m always happy to translate tech speak into easy-to-understand advice for finding your perfect match.
