Advantages of the modular structure:

• Construction of screens of different sizes and resolutions
• Possibility to increase size during upgrade
• Construction of screens of different forms and shapes
• Construction of high resolution screens
• Easy assembly and servicing
• Exchangeability of the modules
• Easy localization of errors
• Possibility of constructing mobile and easily assembling screens

LED modules of the video screens

LED modules are the elements from which LED screens are constructed to different sizes and shapes. The picture on the left shows module with the resolution of 8x8 pixels and pixel structure: 2 Red, 1 Green, 1 Blue. The bottom left picture shows enlarged pixel. LED modules - segments for building LED screens of all sizes and resolution (like building blocks).

Essential parameters of a LED module:

• Pitch (distance between pixels, mm)
• Resolution (number of pixels in a module)
• Linear size (height and length)
• Brightness in cd/sq.m (nit)
• Construction - for the indoor or outdoor use
• Energy consumption
• Viewing angles (horizontal and vertical)
• Pixel composition (number of LEDs that make up a pixel)

One of the main parameter of a LED module is pitch - distance between pixels (dots). The smaller is the distance between pixels the higher the resolution of the LED screen.

Three LEDs pixel

Initially the pixel composition was based on two red lamps (2R1G1B) due to low luminous intensity of red LEDs. The consecutive connection of two red LEDs was optimal in power consumption, while the 4-lamp pixel helped to uniformly fill the irradiating screen surface.

However, when brighter Red LEDs appeared on the market, the pixel structure of 1R1G1B became accessible up to pitch 38 mm. At large viewing distance the pixels 1R1G1B and 2R1G1B are perceived as being the same. But at close range the 2R1G1B could seem excessively reddish, created red background and distorted coloring. All these negative features were eliminated by the use of 1R1G1B pixel structure.

Another advantage of 1R1G1B pixel is the increase in black screen surface area that helps to improve contrast of the image in bright sunlight or with bright ambient street lights around.

SMD screens

With the appearance of SMD LED (3 LEDs - red, green and blue - in the same case) it became possible to start production of SMD modules with the pitch smaller than 10 mm.