led display software adjust brightness
Is it useful to adjust the brightness of the led display by software? We know that there are two ways to adjust the brightness of the full-color display: automatic adjustment and manual adjustment. Among them, automatic adjustment is an intelligent adjustment method of brightness adaptively according to the ambient brightness, and manual adjustment method is realized through software. Is it useful to adjust brightness through software?
At present, the software adjusts the brightness, which is generally 256-level adjustable. In fact, the software is just an operation interface. The PWM duty cycle of the LED display driver is finally changed through the operation of the software to realize the change of brightness.
Here is an example of how the duty cycle controls the brightness:
In a period T (T=Ton+Toff), duty ratio=Ton/T, increasing Ton, the average current flowing through the LED lamp will increase, and the LED brightness will increase, otherwise, reducing Ton, the average current will decrease. Small, the LED brightness is reduced.
There are two ways to control the brightness of LEDs:
One is to change the current flowing through the LED. Generally, the continuous working current of the LED tube is about 20 mA. Except for the saturation phenomenon of the red LED, the brightness of other LEDs is basically proportional to the current flowing through. The other method is to use The visual inertia of the human eye uses the pulse width modulation method to achieve grayscale control, that is, the light pulse width (ie duty cycle) is periodically changed, as long as the period of repeated lighting is short enough (ie the refresh frequency is high enough), the human The eye cannot perceive the shaking of the light-emitting pixels. Because pulse width modulation is more suitable for digital control, almost all LED screens use pulse width modulation to control gray levels today when microcomputers are generally used to provide LED display content.
At present, the brightness of the outdoor full-color LED display must be more than 1500cd/m2 to ensure the normal operation of the display, otherwise the displayed image will be unclear because the brightness is too low. However, at present, the brightness of many outdoor LED screens exceeds 5000cd/m2, which is good during the day, but is prone to light pollution at night, causing trouble to nearby residents.
Therefore, it is very necessary to determine the brightness of the LED display. Adjusting the brightness through software is a necessary method, and it is also a common practice in the industry, which is a useful way. In addition, LED display managers are required to have the ability to operate daily control software and playback software. After the completion of the display screen project, manufacturers will have special training for the software, the purpose is to help customers get started with management operations as soon as possible.
At present, the software adjusts the brightness, which is generally 256-level adjustable. In fact, the software is just an operation interface. The PWM duty cycle of the LED display driver is finally changed through the operation of the software to realize the change of brightness.
Here is an example of how the duty cycle controls the brightness:
In a period T (T=Ton+Toff), duty ratio=Ton/T, increasing Ton, the average current flowing through the LED lamp will increase, and the LED brightness will increase, otherwise, reducing Ton, the average current will decrease. Small, the LED brightness is reduced.
There are two ways to control the brightness of LEDs:
One is to change the current flowing through the LED. Generally, the continuous working current of the LED tube is about 20 mA. Except for the saturation phenomenon of the red LED, the brightness of other LEDs is basically proportional to the current flowing through. The other method is to use The visual inertia of the human eye uses the pulse width modulation method to achieve grayscale control, that is, the light pulse width (ie duty cycle) is periodically changed, as long as the period of repeated lighting is short enough (ie the refresh frequency is high enough), the human The eye cannot perceive the shaking of the light-emitting pixels. Because pulse width modulation is more suitable for digital control, almost all LED screens use pulse width modulation to control gray levels today when microcomputers are generally used to provide LED display content.
At present, the brightness of the outdoor full-color LED display must be more than 1500cd/m2 to ensure the normal operation of the display, otherwise the displayed image will be unclear because the brightness is too low. However, at present, the brightness of many outdoor LED screens exceeds 5000cd/m2, which is good during the day, but is prone to light pollution at night, causing trouble to nearby residents.
Therefore, it is very necessary to determine the brightness of the LED display. Adjusting the brightness through software is a necessary method, and it is also a common practice in the industry, which is a useful way. In addition, LED display managers are required to have the ability to operate daily control software and playback software. After the completion of the display screen project, manufacturers will have special training for the software, the purpose is to help customers get started with management operations as soon as possible.
