The Difference Between LED and LED-Lit Laptop Displays

Difference Between LED and LED-lit

We bet you just asked Google for the difference between LED and LED lit laptop screens. As you shop for a brand-new laptop. You’ll find that modern displays have all kind of names: full-high definition, 4K, OLED the list goes on. But the two you’re sure to run into the most are LED and LED-lit. What’s the difference? And how will they make or break your viewing experience; especially when it comes to activities like gaming and graphic design? In what follows, we’ll go over the pros and cons of LED and LED-lit displays. As well as why you might prefer one over the other. Let’s go.

What’s an LED Display?

In an effort to better sell their products, companies often release their products with a buzzword as a marketing tool. This can be pretty misleading when you’re shopping for a laptop.

In today’s case, it’s the term “LED” that can trick users into thinking that they’re buying a laptop with a super-advanced LED display. When, in reality, an LED screen is basically an LCD display but with a different type of back-lighting.

The traditional method of back-lighting an LCD display is to use a CCFL (cold cathode fluorescent lamp). This type of lamp has been around for decades and was responsible for producing high-quality images.  

But there’ve always been a few disadvantages to this technology including poor color reproduction and abysmal contrast ratios.

To fix some of these issues, a different type of back-light was introduced.  Nowadays, displays are manufactured using the same LCD screens but with LEDs (light-emitting diodes) for the backlighting.

An LED display generates an image by making each pixel a direct composite of three different colors of LEDs: red, green, and blue.

It produces perfect black levels by completely shutting down all pixels, producing no light whatsoever.  In this way, a laptop with an LED display can offer a particularly high contrast range and color depth.

LED displays can come in a very large format like at sports stadiums, roadside signs, and music concerts since they’re perfectly designed to be viewed from a distance.

What is an LED-Lit Display?

An LED-lit display is a display where white light (generated by phosphor-coated near-UV LEDs) is first diffused. Then filtered into small segments of red, green, and blue light.  After which, the small colored sections are selectively turned on with variable magnitudes to pass through the front of the display.

This diffusion of white light paired with the tiny pixels allows for a more fluid display that you can view up close, as in a TV or a computer display.  

However, since the white light source is always enabled, the ability to completely turn off light is limited un-like LED displays.  Some light will always leak through a disabled pixel, so the achievable black level is reduced.

The energy efficiency of LED-lit displays is also less than an LED display because the white light source always remains enabled, even when the display is supposed to be black.  Moreover, light energy is lost in the process of diffusion, filtering, and magnitude adjustments, which results in even lower efficiency.

Some modern LED-lit displays attempt to address this issue by utilizing zoned backlighting to enhance energy efficiency.  Zone backlighting is a method where the backlight is divided into multiple zones.

The intensity of light in each zone is altered depending on the local zone contrast requirements of the image.

What About Edge-Lit LED Displays?

Now let’s discuss the difference between back-lit LED displays and edge-lit LED displays since these are the two types of displays most associated with laptops.  

Let’s begin by saying that the main difference between both types is how the LEDs are positioned and how many LEDs are used.

Back-Lit or Full LED Displays

Back-lit LED displays (sometimes known as Full LED displays) have the LEDs arranged in a grid across the whole display, similar to a traditional LCD with a fluorescent lamp.

By lighting the screen from behind, the display offers several advantages; the most important being more control over where the light occurs on the screen.  It also allows for a more even spread of light across the image, but that’s not the case with all back-lit LED displays.

Accordingly, there are two main types of back-lit LED displays:  back-lit with local dimming and back-lit without local dimming.

  • Back-lit with local dimming (full-array) – this type of LED display has the LEDs divided into blocks.  Each block is turned on or off independently of the other blocks.
    If a block of LEDs is turned off, you’ll get a true black signal that’s not possible with fluorescent lamps.  Various parts of the screen can have blocks enabled or disabled at the same time, allowing the display to deliver better contrast and a better picture than traditional LCD displays.

    The drawback, however, is that you get an image that’s a mixture of bright and dark areas.  This is likely because some LED blocks are participating in both the light part and dark part. 

    It’s also worth mentioning that the power consumption of this type of display is greater than edge-lit LED displays.  But it won’t be as thin as edge-lit models.

  • Back-lit without local dimming (direct-lit) – this type of back-lit displays has LED lights located behind the screen but lacks the ability to turn off certain zones of the screen.  Compared to edge-lit models, this type offers more uniform lighting across the screen which eliminates the light-pooling of edge-lit displays.
    However, they don’t have the enhanced contrast ratios of a model with local dimming.

Edge-Lit Displays

As for edge-lit displays, this type features LED lights located around the edge of the screen.  Laptop manufacturers market them differently.  For instance, Acer calls this kind of backlighting, Nano-Edge and Dell calls it InfinityEdge.

The technology works the same in either case:  the LEDs in an edge-lit display are positioned around the perimeter of the LCD screen.  And the emitted light is spread across the back of the panel via light guides.

Edge-lit displays have several advantages including being very slim and slender compared to back-lit models.  If you see a display that almost disappears when you look at it from the side. You can bet it’s an edge-lit screen.

Laptops with such displays look quite aesthetically pleasing in just about any room. And they’re also cheaper than models with back-lit screens.  However, they do come with a few disadvantages.

Edge-lit LED displays don’t have the best image quality.  And unfortunately, the improvement compared to traditional LCD screens isn’t as substantial as with back-lit models.

The picture will tend to display inconsistency in the spread of the back-light across the whole screen. This is most noticeable if you’re in a darkened room since you may see light pooling. This happens when dark scenes highlight brighter areas around the edge of the screen.

To Sum Up

An LED backlit display is basically an LCD screen that fixes some of the issues with CCFL backlighting. LED-lit displays diffuse white light into segments of red, green and blue. To address issues with energy in-efficiency, some LED-lit screens use zoned-backlighting technology. Edge-lit backlighting LEDs are positioned around the perimeter of the LCD screen. The result is a slim, aesthetically pleasing display compared to displays with other forms of backlighting. So, choosing the best display for your laptop depends on your needs and situation.