Understanding LED Displays: Key Features and Benefits

What is LED?

LEDs are Light Emitting Diodes, a type of semi-conductor, which send electronic signals into infrared rays or light. As opposed to LCD, which are liquid crystal displays that use the light emitting properties of liquid crystals. Liquid crystals do not emit light directly.

Advantages of LED over LCD

LED displays are not limited in size. The largest LCD monitor measures only 110″ diagonally. When LCD monitors are placed together the bezel outline will always be visible. LED consumes less power. LED produce more vivid lighting effects dues to being able to produce strong contrasts between light colors and dark colors. There continue to be many issues with LCD backlights. LCDs are usually installed as a grouping of a number of LCDs. If one of those LCDs has to be replaced it is impossible to match the colors of original installed LCDs.

Pixel Pitch – Pixel Pitch refers to the distance between pixels on an LED module. For example a P1.25 mm means that the space between pixels is 1.25 mm. The lower the pixel pitch, the higher the overall screen resolution will be. The lower the pixel pitch the more pixels there are on a module.

The Pixel Pitch also indicates the minimal optimal viewing distance from the screen. For example, a 3..91 mm pixel pitch has a minimal viewing distance of 12.8 feet. This means that at 12.8 feet your eyes will not see individual pixels but be able to perceive the thousands of LEDs as a continuous display. A screen with a pixel pitch of 6.25, for example has a minimal viewing distance of 20.5 feet.

There have been rapid advancements in the miniaturization of LED bulbs and as a result we have available SMD pixel pitches as low as P0.9 and COB pixel pitches as low as P0.6.

Nits-Lumens-Brightness

Brightness of an LED screen is measured in candelas per square meter (cd/m2), informally called nits. For indoor LED screens 300-1000 nits will provide the required brightness.

The sun emits 2500 nits per square meter. For outdoor applications 4500 nits is the minimum recommended brightness in order to prevent direct sunlight from washing out the images. For permanent outdoor LED screens 6000 nits and above are preferable.

The use of the term Nits or Lumens is interchangeable, as the calculations of brightness are identical.

What are the advantages of LED walls over projection?

LED video walls offer a far superior image quality when compared to projection. The colors emanating from an LED screen are very vivid and very high in contrast which makes the content really “pop”! This superiority is magnified even more in in environments with the intrusion of ambient light. Most sanctuaries have windows and therefore have ambient light. Ambient light results in dim, fuzzy images from projection. No projector is able to achieve the image quality of an LED video wall in a venue with ambient light. LED screens are not affected by theatrical lights. Projected images will degrade by lighting. Shadows created by lighting have no effect on LED video screens. Where multiple projectors are used the images need to overlap. This is called edge blending. If a single projector is moved the process of edge blending must start all over.