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SMD Outdoor Full Color LED Display Modules What Do You Know About The Relationship Between Grayscale And Brightness?
Sep 29, 2017


SMD Outdoor Full Color LED Display Modules has been widely used in today's commercial life, but some common sense you may not know. For example, what is SMD Outdoor Full Color LED Display Modules gray, brightness, what is the relationship between them? The following Xiaobian to tell you about it
SMD Outdoor Full Color The brightness of the LED Display Modules can also be referred to as the brightness of the SMD Outdoor Full Color LED Display Modules. Gray level, also known as the middle tone, mainly for the transmission of pictures, respectively, 16, 32, 64 three ways, it uses the matrix approach to the file pixel processing 16,32,64 level, so that the transmission The picture is clearer. Whether it is monochrome, two-color, full-color SMD Outdoor Full color LED Display Modules, to display images or animation need to constitute the pixels of each LED light gray scale adjustment, the adjustment of the fine degree is what we usually call the gray Degree level.
There are two ways to divide gray: one is to change the current flowing, one is pulse width modulation. 1. Change the current flowing through the LED. General LED tube allows continuous operating current in 20 mA or so, in addition to red LED saturation phenomenon, the other LED gray scale is basically proportional to the current flowing; another method is the use of human eye visual inertia, with pulse width Modulation method to achieve gray-scale control, that is, periodically change the width of the optical pulse, as long as the repetition of the light cycle is short enough, the human eye is not feeling the luminous pixels in the jitter.
Because pulse width modulation is more suitable for digital control, so in the general use of microcomputer to provide LED display content today, almost all of the SMD Outdoor Full Color LED Display Modules are using pulse width modulation to control the gray level.
 LED control system is usually by the main control box, scanning plate and the three parts of the control device. The main control box obtains the color brightness data of one screen pixel from the computer's display card and then reallocates to several scanning plates. Each scanning plate controls the number of rows (columns) on the SMD Outdoor Full Color LED Display Modules, and Each row (column) on the LED display signal is transmitted in a serial manner. There are two modes for serial transmission of control signals.
One, one is to focus on the control panel to control the gray point of each pixel, the scan board from the control box of the pixels of the gray value of the decomposition, and then the LED signal to open the line in the form of pulse by serial Transferred to the corresponding LED, to control whether it is lit. This method uses fewer devices, but the amount of serial transmission of data is large, because in a repeated light cycle, each pixel in 16 grayscale need 16 pulses, 256 levels of gray need 256 pulses, due to the device operating frequency limit, generally only make SMD Outdoor Full Color LED Display Modules to 16 gray scale.
Second, one is pulse width modulation. The contents of the serial transfer of the scan board are not the switching signals of each LED but an 8-bit binary gray value. Each LED has its own pulse width modulator to control the lighting time. In this way, in a repeated light cycle, each pixel in 16 grayscale only need 4 pulses, 256 gray level only 8 pulses, greatly reducing the serial transmission frequency. With this decentralized control of LED gray scale method can be very convenient to achieve 256 gray-scale control.
SMD Outdoor Full Color LED Display Modules Gray and Brightness is one of the important parameters of the product, in order to better use SMD Outdoor Full Color LED Display Modules, we need to understand the SMD Outdoor Full Color LED Display Modules gray and brightness relationship.