Impact of PWM technology on LED electronic displays
Impact of PWM technology on LED electronic displays
At present, the LED electronic display screen more and more frequently in a variety of occasions, its excellent display effect attracts more and more customers to buy and use, but many people in the use of cell phones or cameras on the LED electronic display screen shooting, but it is likely to find that the photo does not come out of the effect of the human eye to see, appear such as water ripples and other things. So how is it? Here from the refresh frequency and grayscale level and so on a few places to briefly analyze.
LED electronic display screen refresh frequency
Refresh frequency” refers to the number of screen updates per second, usually with Hertz (Hz as the unit of expression, generally speaking, the refresh frequency of 3,000Hz or more, for high-performance LED electronic display. The higher the visual refresh frequency, the more stable the screen display, the smaller the visual flicker, the low “visual refresh frequency” of the LED electronic display screen in addition to the impact of video, photography, horizontal horizontal stripes, but also similar to tens of thousands of light bulbs at the same time flickering image, the human eye in the viewing of the discomfort may occur, and even cause damage to the eyes. The human eye may experience discomfort and even eye damage when viewing.
Although the human eye already feels continuous images with a visual refresh rate of 60Hz or more, the higher the visual refresh rate, the more stable the displayed image is, and the less fatiguing it is to the human eye. In today's high-quality video, in order to get a more detailed picture, such as exciting playback or close-up photography process, there are a lot of high-speed camera shooting at more than 1,000Hz per second. At this point, the LED electronic display will also be captured, high-speed shutter is still able to present a continuous picture (no black scan lines) or continuous color gradation, is a great challenge.
Gray scale of LED electronic display
Gray level” refers to the various colors in the darkest and brightest colors, with different changes in the color class, generally speaking, the gray level in 14 bits (bit or more, i.e., at least 16,384 kinds of color class or more, for high-performance LED display. If the number of grayscale is not enough, the lack of color levels will occur or gradient color gradient is not smooth enough, and can not fully display the color of the film. Make the LED display effect is greatly reduced. Some low performance LED display in 1/500 shutter, can already be detected a clear color distribution, if I will increase the shutter speed, such as 1/1,000 or 1/2,000 will be more obvious.
Knowing the LED electronic display screen several core components, such as LED switching power supply, LED driver chip, LED lamp beads, etc., for the LED electronic display screen refresh frequency and grayscale level, LED driver chip directly determines the LED display screen in the visual refresh frequency, grayscale level of representation. At present, the LED driver chip, the highest new technology for the “ScrambledPWMS-PWM technology” S-PWM technology is to improve the radical pulse width modulation (PWM technology, which will be an image of the on-time dispersed into a number of shorter on-time, in order to increase the overall visual refresh rate. Further explanation, the new generation of LED driver chip built-in S-PWM technology, can be the original each frame (frame counting once (LED grain ONLED grain OFF way, the average dispersion into a number of counts, and each dispersion of equal parts, can be maintained before the original dispersion of the On/Off ratio, the S-PWM technology provides a radical pulse width modulation (PWM), which will spread an image on time into a number of shorter on time to increase the overall visual update rate.
S-PWM technology provides different counting modes, thus increasing the image refresh rate up to 64 times. If S-PWM is used to increase the video refresh rate, the visual refresh rate can be easily increased by 64 times with a low-level clock (e.g., 5 MHz), and can reach over 4,800 Hz. Compared with the general video visual refresh frequency of at least 10 times higher than the ability to also prevent the occurrence of high-frequency electromagnetic interference (EMIissu over-voltage surge (Overshoot and under-voltage surge (Undershoot) problem.
S-PWM driver chip LED electronic display, with a digital camera high-speed shutter for imaging, still does not appear horizontal black scanning lines and color block distribution of its visual refresh frequency, grayscale level of representation, far beyond the use of aggressive switching-type driver chip LED electronic display.
High-quality LED driver chip, built-in S-PWM technology, so that the refresh frequency of up to 3840Hz gray level up to 16bit high-speed shutter camera, to achieve good results.
LED electronic display screen refresh frequency
Refresh frequency” refers to the number of screen updates per second, usually with Hertz (Hz as the unit of expression, generally speaking, the refresh frequency of 3,000Hz or more, for high-performance LED electronic display. The higher the visual refresh frequency, the more stable the screen display, the smaller the visual flicker, the low “visual refresh frequency” of the LED electronic display screen in addition to the impact of video, photography, horizontal horizontal stripes, but also similar to tens of thousands of light bulbs at the same time flickering image, the human eye in the viewing of the discomfort may occur, and even cause damage to the eyes. The human eye may experience discomfort and even eye damage when viewing.
Although the human eye already feels continuous images with a visual refresh rate of 60Hz or more, the higher the visual refresh rate, the more stable the displayed image is, and the less fatiguing it is to the human eye. In today's high-quality video, in order to get a more detailed picture, such as exciting playback or close-up photography process, there are a lot of high-speed camera shooting at more than 1,000Hz per second. At this point, the LED electronic display will also be captured, high-speed shutter is still able to present a continuous picture (no black scan lines) or continuous color gradation, is a great challenge.
Gray scale of LED electronic display
Gray level” refers to the various colors in the darkest and brightest colors, with different changes in the color class, generally speaking, the gray level in 14 bits (bit or more, i.e., at least 16,384 kinds of color class or more, for high-performance LED display. If the number of grayscale is not enough, the lack of color levels will occur or gradient color gradient is not smooth enough, and can not fully display the color of the film. Make the LED display effect is greatly reduced. Some low performance LED display in 1/500 shutter, can already be detected a clear color distribution, if I will increase the shutter speed, such as 1/1,000 or 1/2,000 will be more obvious.
Knowing the LED electronic display screen several core components, such as LED switching power supply, LED driver chip, LED lamp beads, etc., for the LED electronic display screen refresh frequency and grayscale level, LED driver chip directly determines the LED display screen in the visual refresh frequency, grayscale level of representation. At present, the LED driver chip, the highest new technology for the “ScrambledPWMS-PWM technology” S-PWM technology is to improve the radical pulse width modulation (PWM technology, which will be an image of the on-time dispersed into a number of shorter on-time, in order to increase the overall visual refresh rate. Further explanation, the new generation of LED driver chip built-in S-PWM technology, can be the original each frame (frame counting once (LED grain ONLED grain OFF way, the average dispersion into a number of counts, and each dispersion of equal parts, can be maintained before the original dispersion of the On/Off ratio, the S-PWM technology provides a radical pulse width modulation (PWM), which will spread an image on time into a number of shorter on time to increase the overall visual update rate.
S-PWM technology provides different counting modes, thus increasing the image refresh rate up to 64 times. If S-PWM is used to increase the video refresh rate, the visual refresh rate can be easily increased by 64 times with a low-level clock (e.g., 5 MHz), and can reach over 4,800 Hz. Compared with the general video visual refresh frequency of at least 10 times higher than the ability to also prevent the occurrence of high-frequency electromagnetic interference (EMIissu over-voltage surge (Overshoot and under-voltage surge (Undershoot) problem.
S-PWM driver chip LED electronic display, with a digital camera high-speed shutter for imaging, still does not appear horizontal black scanning lines and color block distribution of its visual refresh frequency, grayscale level of representation, far beyond the use of aggressive switching-type driver chip LED electronic display.
High-quality LED driver chip, built-in S-PWM technology, so that the refresh frequency of up to 3840Hz gray level up to 16bit high-speed shutter camera, to achieve good results.