When it comes time to select the best display option for your project, which monitor type should you choose LCD or LED? The best way to answer this question is to understand the similarities and the differences between the two as well as which features make one or the other better for various uses.
The first thing to point out is that “all LED monitors are LCD monitors, but not all LCD monitors are LEDs.” It’s just like saying all Mercedes are cars, but not all cars are Mercedes. This means LEDs are actually a subset of the larger LCD umbrella. It would really be more accurate if LED monitors were called LED LCD monitors.
With that explained, let’s talk about the building blocks of LCD technology. LCD stands for Liquid Crystal Display. With the help of a complicated mix of science and engineering (which we won’t get into here) these liquid crystals are lit from behind to create images. Like a mosaic, each image is a collection of thousands of individual pixels – small dots that can emit colored lights.
All LCD screens are structured the same. Every pixel is made up of two glass sheets with the liquid crystals sandwiched between. From the back of the display (furthest from the viewer) to the front (closest to the viewer) the layering order is always: backlights, sheet #1, liquid crystal, sheet #2 with color filters, screen. (1)
So, where do these two display options diverge? Easy answer – it’s not that they are backlit, but HOW they are backlit.
Standard LCD monitors use fluorescent lamps as their backlights. Uniform spacing of the lamps behind the screen produces consistent lighting. As a result, the display will show virtually the same brightness levels across all areas of the screen.
LED monitors are lit using Light Emitting Diodes. These are extremely tiny lights that can be positioned in full-array behind the screen or just around some or all of the outer edges (not going to dive into the latter in this article). With full-array backlighting, the small lights are laid out behind the screen evenly, as they are with LCD set-ups. BUT, the big difference is the LED lights are arranged in zones that can be locally dimmed to increase contrast. If one region of an image needs to be very light while another region needs to be very dark (like for example, a brightly lit house shown against a nighttime sky) a full-array LED screen can maximize both the light and dark pixels simultaneously. The ability to create this greater contrast leads to greater picture quality – the better the contrast ratio, the better the image. (1)
The biggest factors when deciding between an LCD or LED display are applications and cost.
If image quality is of the utmost importance then LED is definitively the best choice. The brighter images and superior picture quality make LEDs ideal for very large video walls. Additionally, seams are invisible even when installing many panels. When budget is more of a consideration than resolution, LCD is typically the way to go.
There are a few other features to keep in mind when selecting one or the other. If the screens will be used in an outdoor setting then LED is a must. If you’ll be running images or video for long, continuous periods, LCD is the better pick. Finally, don’t forget about longevity – LCD monitors usually last 5-7 years while LED monitors offer about 20,000 hours of display time (which translates to roughly 6-10 years in average environments with non-continuous play). (2)
Like LCD versus LED, there are many similar yet different AV products available. Often times no one item is the perfect solution for every customer. That’s why Immedia promises to keep you informed throughout all stages a project. We’re experts at this stuff! Give us a shout if you’re ready to explore your options.
(2) Mike Lofaro, Design Engineer, Immedia Integrated Technologies