To make the best choices for LED display, some factors need to be taken into accounts. The following is very important to guide you to chose the right ones.

Display environment: the proper and exact location of Led display
Outdoor: To overcome the weather factors like sun and rain. The led display has to raise luminance to have better performance under the sunlight. Besides, the led display needs to have water proof, anti-dust and sunshading board. Outdoor display has two kinds of model: matrix and screen. Each pixel is composed of red, green and blue led light. The content of led display is variable. The led light can save energy consumption and life time of led light is longer than traditional lamp. The led light is brighter as well. The viewing angle is about 30. The outdoor display application also has advertising and traffic guide functions.
Message content: the massage that you would like to dispatch.
Viewing distance and time: the message content must be easy to read and the distance must be proper to tell the message Viewing distance and time: the message content must be easy to read and the distance must be proper to tell the message.

1.Environment
The luminance of LED display is much higher than LCD display. The glow emitted of LED display is not from heat or discharge, it is from luminescence instead. The life time will be over 80000HRS and its application can be separated into outdoor and indoor LED display. The indoor application includes Stadium, entertainment center, concert and railway station and airport. The outdoor application includes Amusement park, highway and some others.
Indoor：Because viewing distance that indoor display needs is relatively near, it does not need to adopt the ultra and high brigness models. As for the resolution, have two kinds of 5φ and 3φ commonly. There are matrix type , screen type, color displays and already enters full color technological era , visual angle range is about120 degrees
Outdoor： To overcome the weather factors like sun and rain. The led display has to raise luminance to have better performance under the sunlight. Besides, the led display needs to have water proof, anti-dust and sun shading board. Outdoor display has two kinds of model: matrix and screen. Each pixel is composed of red, green and blue led light. The content of led display is variable. The led light can cut energy consumption and life time of led light is longer than traditional lamp. The led light is brighter as well. The viewing angle is about 30. The outdoor display application also has advertising and traffic guide functions.

2.Message content
The information you would like to display will help you to select the right led display. The following basic selection will meet your requirement:
Moving message signs
The moving sign can be applied in government institutes to display the latest news, electronic billboard, time and so on. Besides Chinese and English letters, it can display animations and graphs.
drawings, charts and trend mark
It also can be applied in production line of factory, business service introduction,
Traffic guides, Business Image and Calendar. Besides Chinese and English letters, it can display graphs and animations as well.
Video display-Full color display, Sun-moon Display, video record and pictures, synchronous and asynchronous
Synchronous and asynchronous moving sign can display graphs, letters and video. These moving signs have often seen in Markets, railway stations, stadiums and traffic guides, exhibitions and concerts and so on. It can display formats like AVI 、MOV、MPG、DAT、VOB and so on. It even can play movies by (VGA+VIDE), Video and VGA etc.

3. Viewing distance and time

However, when audience’s not fixed, according to research report from Japan, the viewing distance and driving speed are as following table15.4.1-3 for reference. The maximum viewing distance =CI x letter height. The calculation and design for led display have to consider some factors including driving speed and viewing distance that can make driver to tell message content within limited time.

Table 15.4.1-3 The viewing distance vs. letter dimension and driving speed

LED Display Installation: