Thursday, February 13, 2014

Frame Changing Frequency and Refresh Rate of LED Display

Frame Changing Frequency and Refresh Rate of LED Display

LED display is full digital equipment, which is driven by the impulse current. The Gray-scale and Brightness is realized by PWM (pulse-width-modulation). The illumination of LED is pulse-type. When the frequency of pulse repeating is not fast enough, the human sight would feel twinkling. So, how high the frequency can eliminate the twinkling? Ferry-Porter rule points out, when watching a pulse illumination, coming with the improvement of the pulse repeating frequency, there is a critical point for human eyes. People will feel the illumination continuous, when the frequency is higher than the critical point. That’s we call Critical Fusion Frequency.

Refresh Rate defines how many times the content on the display repeats in each second.
According to Ferry-Porter rule, and our experience, to eliminate the image twinkling, the refresh rate of full color LED display should be higher than 240Hz; Full color LED display with the brightness higher than 4000nits, the refresh rate must be higher than 400Hz.
If there’s camera catching the image and video on the LED display, or relay a TV broadcast (When rent the LED display to stages, arenas, etc events), it’s necessary to enhance the refresh rate to 2000Hz+.
To LED display, it enough to ensure the smooth image and video with the 50/60Hz Frame-Changing Frequency. And the meaning is not so big to improve further.


 As a disadvantage of high refresh rate, the LED display lifetime would be short, to a certain extent.
* When bring out a solution,  sales engineers will consider well your application, and provide the most suitable one to you.




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SMD LED outdoor display

SMD LED outdoor display
SMD LED outdoor display

Questions before LED display quote

SMD outdoor LED video display global supplier If you need a LED screen quote, please answer carefully the questions below so we can propose you the correct specifications to generate the quote for any LED screen for you isntantly. 1.Your contact details Name: company: email address: telephone number: Nextel: address: 2.Your led screen information in the application: - Type of LED screen Displays for text, images or video installation type : indoor or outdoor With various colors or Monochrome - minimum viewing distance - Approximate size led screen width led screen height - Type of communication preferred type of control system simple control system/ advance live video controller control distance wireless controller( internet/wifi)/ less than 100 meter/less than 400 meters/over 400 meters - Function or intended purpose rental or fixed outdoor advertising Best regards, Sally Peng Oversea Sales Manager Cell: 0086 18898792143 Gmail: pengsally@gmail.com Skype/Wechat: sallypwp