Modern display screens are categorized by a number of confusing labels such as HD, 3D, 4K, and more! The two most important acronyms, however, are LCD and LED. LCD stands for ‘Liquid Crystal Display’, while LED stands for ‘Light-Emitting Diodes’.
You’re probably wondering what the difference is, right?
Well, it may surprise you to know that both LCD and LED screens are based on LCD technology. In fact, an LED screen is a specific type of LCD screen.
That doesn’t mean that LCD and LED displays are exactly the same, though. On the contrary, there are key differences that are important to understand. Keep reading to find out what these are.
What is an LCD Screen?
The science behind LCD technology can get pretty complicated, but the basic principles are easy to understand.
An LCD panel consists of two sheets of polarizing glass with a liquid crystal solution in between. These liquid crystals are neither solid nor liquid, but somewhere in between. This means that liquid crystals can have either a highly-structured, geometric shape or a fluid, unstructured shape.
It turns out that because of these interesting properties, liquid crystals are very useful in digital display technology.
You see, when you run an electric current through the liquid crystals, it causes them to change their shape and alignment (twist and untwist) in such a way as to allow light to pass through.
The changing alignment of these liquid crystals allows for the control of the light passing through the second sheet of polarized glass. This is how the picture forms on the screen. Because LCDs cannot create any light by themselves they need to be backlit by using ‘cold-cathode fluorescent lamps’ (CCFLs).
The CCFLs are placed evenly behind the screen to ensure that the entire screen has even and consistent lighting.
While CCFLs were traditionally used in LCD displays, nowadays things have changed a bit and many LCD screens actually use LED lights instead of fluorescent lamps.
To sum up. The structure of an LCD display, from the back to the front, is as follows:
1. Backlights (CCFLs or LEDs)
2. Polarized glass sheet #1
3. Liquid crystal solution
4. Polarized glass sheet #2
5. The screen
What is an LED Screen?
While LCD screens use fluorescent lamps to provide backlighting, LED screens use ‘light-emitting diodes’, which are a type of small light.
The placement of lights on an LED screen can also differ. For an LCD screen, the fluorescent lights are always placed behind the screen, but for LED displays, the light-emitting diodes can either be placed behind the screen or around the edges of it.
These two methods of backlighting are known as ‘full-array’ backlighting and ‘edge lighting’. With full-array backlighting, LEDs are placed evenly behind the screen, while with edge lighting, the LEDs can be placed either around the bottom edge, top edge, side edges, or all edges of the screen.
LED panels are favored for outdoor purposes such as billboards, store signs, floor panels, or large displays.
What are Pixels?
Pixels are the basic units of any digital display. Pixels are tiny dots that give off colored light. For each pixel, there are three subpixels, made up of red, yellow, and green (hence, RGB) light respectively.
Pixels combine in a mosaic-like fashion to form a picture on the screen. Pixels are the building blocks of every kind of digital display, from your phone screen to your TV. And if you look closely, you can see them.
The light that emits from each pixel rapidly changes, allowing a moving picture to display on the screen. In LCD displays, liquid crystals switch pixels on and off by controlling the flow of light.
Advantages of Using an LED Screen
There are numerous benefits to using LED screens.
For starters, LED displays are more energy-efficient as they consume less power than regular displays. LED screens also produce a clearer, crisper picture than LCDs.
LED technology produces a better picture for a couple of reasons. Firstly, LED displays work with a distinct RGB color wheel which allows them to produce sharper, more realistic colors.
Secondly, you can dim light-emitting diodes. For LED displays using full-array backlighting, LEDs are arranged in zones. These zones are then illuminated or dimmed as required.
Why is this important?
Dimming allows the LEDs to match the demands of the picture. LCDs can’t completely prevent light from passing through, even during dark scenes, so dimming the LEDs themselves aids in creating realistic dark/light contrast in the picture. A high contrast ratio means a better picture quality.
The precision illumination created through LED local dimming results in a clearer and better picture overall.
It’s important to note that edge-lit LED displays cannot make use of local dimming and therefore full-array backlit LED screens generally offer the best picture quality.
However, because of the configuration of LED lights in edge-lit displays, they tend to be thinner and therefore don’t cost as much.
Comparing LED to LCD
For the reasons explained above, full-array LED screens are almost always superior to regular LCDs. Edge-lit LEDs aren’t always better quality than regular LCDs, but they are generally more affordable and are a great option if you’re on a budget.
While backlighting is important, you should also take into account the resolution when buying an LED screen. Resolution is the number of pixels displayed on the monitor. The more pixels you have, the more dynamic the colors in the display. For example, an HD (high-definition) monitor is 1920×1080 pixels.
LED Displays That Meet All Your Needs
When sourcing an LED screen, you need a provider that is not only knowledgeable but experienced. Here at Xiyinguang, we offer a variety of LED display solutions to meet all your needs and requirements.
From outdoor LED screens to floor displays, to video walls, we have it all!
So, what are you waiting for? Contact us today for a quote.