What’s better, an LED screen or an LCD screen? What about OLED? Is that a kind of LED screen? And what’s this I hear about QLED? The whole thing starts to sound like alphabet soup, so if you’re scratching your head, you’re not alone. Fear not, as we’re going to try to make this simple. Enjoy this handy breakdown, represented in a few simple concepts, designed to illuminate you (pun intended).
LED vs. LCD
An LED TV is an LCD TV.
What’s that now? Then why all the debate? First, let’s distinguish between backlighting and display. Generally speaking, these are the two elements that determine the quality of the picture. Liquid crystal display (LCD) refers to the technology that does or doesn’t allow light to shine through your screen. Electric currents pass through the liquid, and the crystals align themselves in such a manner as to either allow light to pass through, or block it from doing so. Think of the LCD screen as a series of tiny gatekeepers, each allowing light to pass or not to pass, thus creating the picture on the screen. LCD screens do not create light on their own. For this, they need backlighting.
Traditionally ‘LCD Screens’ were backlit by clunky, under-performing, environmentally-unfriendly cold cathode fluorescent lamps (CCFLs). They lit everything evenly, and thus picture quality lacked contrast. Enter LED backlighting. The light-emitting diodes were superior to CCFLs, and thus began to replace them. Thus, we had LCD screens being backlit by LED lighting. This is what we often referred to as LED screens, and featured sharper contrast.
To recap, as this is important, this all led to a situation where LCD screens backlit by CCFL lighting were known as LCD TVs, whereas LCD screens being backlit by LED lighting were called LED TVs. If you get the picture, let’s move on (there I go again).
Edge Lit vs. Full Array Lighting
All LED backlighting is not created equally. There are actually various configurations, with the most important distinction being edge lit vs. full array. Edge lighting refers to situations where the backlighting is placed along the edge of the screen, either on the bottom/top or sides, or some combination thereof. Full array backlighting means that the lighting is distributed evenly behind the screen. This allows for local dimming, in which portions of the screen can be backlit to varying degrees, depending upon the picture at that moment.
Why is Local Dimming Beneficial?
Because LCD screens aren’t perfect, and therefore can’t completely stop light from getting through. By using less backlighting for portions of the screen that are black, we can create a greater contrast between light and dark. For this reason, full array lighting creates a superior picture, as compared to an edge lit screen. Edge lit screens, however, as you might have guessed, are thinner, more affordable and are superior to the old CCFL screens.
OLED And the Art of Lighting One’s Self
With OLED (organic light emitting diode) screens, we add another twist: each pixel actually lights itself. This technology allows for each pixel in the screen to be on or off, creating great contrast. Without the need for backlighting, OLED screens are also very thin. On the downside, the technology remains pricey, and the longevity of the screens have yet to be proven.
QLED: A quantum leap?
QLED stands for quantum-dot light emitting diode. Unlike OLED, QLED relies upon backlighting, but takes advantage of superior quantum dot colour filter LED lighting, allowing for much better brightness than OLED, at the expense of less contrast.
Have these distinctions all come into sharp focus? (Last time, I swear). At LIGHTVU we pride ourselves on our innovative and eye catching LED displays. Visit lightvu.com today and let us help you create a compelling display!
