How Do LED Walls Work?


  • Sign up for our newsletter and stay up to date!
  • How do LED walls work?

    Consider an LED flat panel for a moment – the “screen” is actually a large white LED grid, placed behind an LCD “mask” that controls what colors come through in each pixel location.  Manufacturing the “mask” is a very advanced process, requiring specialized facilities (of which there are only a few worldwide.) This is why LCD screens come in standard sizes, no matter what the brand.

    LED Walls are what is called “direct-view” technology – the viewer is seeing the light directly from the light source – there is no mask manipulating the pixels. The colors are determined by a controller that is manipulating a “3 in 1” led (three colors in one location) to output the correct color for that pixel, based on the image being sent.

    LED walls are made up of what the industry calls “cabinets” – cabinets are the building block of an LED wall. Cabinets themselves are very simple, with no moving parts (other than perhaps a power supply fan.) Each cabinet usually contains the LED grid – which is the side of the cabinet seen by the viewer. It is a grid of “3-in-1” LEDs, and is made up of sub “modules.” The number of modules varies, but usually 2-6 modules make up one cabinet. The only other components in a cabinet are the power supply, signal receiving board, and various interconnect cables.

    LED cabinets are connected to each other in a “daisy chain” fashion, where the entire video signal is sent to each cabinet. The receiving board within the cabinet has been programmed to know how many pixels of the entire video it is to display, and where it is in the mosaic of cabinets (this programming is done at installation.)

    A properly connected LED wall functions just as a large monitor with a custom aspect ratio (based on the ultimate size of the screen.) A video switcher/scaler contains the LED sending cards, which communicate over Cat6 cable to the LED wall. The switcher/scaler has standard DVI/HDMI and SDI (as well as VGA) inputs – and can either send the image directly to the screen unaltered, or scaled as needed. On larger walls, the switcher may actually communicate to the LED wall as if it were 2-3 smaller screens, and then it “stitches” them together seamlessly – and in this way, larger resolution displays can be created. Layering multiple video sources on top of each other can also be done depending on the switcher/scaler specified.

    At the end of all of this, you have a really large, high contrast, high brightness monitor, to which you can send any standard video signal, from a DVD/Blu-Ray player, to a PC or Mac running ProPresenter, to an Xbox. There are no special requirements on any of these connected inputs.  Depending on the size and aspect of your LED wall, you may wish to configure a custom display size, and create custom content, for ProPresenter.

    >>> What is “pixel density?



    Return to LED FAQ


  • Sign up for our newsletter and stay up to date!