Analysis of refresh frequency and gray level of LED display screen

With the development and application of indoor LED displays more and more, you can see that LED displays are widely used in command centers, monitoring centers and even studios. However, judging from the overall performance of the LED display system, can these displays meet the needs of users? Can the images displayed by these LED displays conform to human vision? Can these led display screens withstand the test of different shutters and different angles of the camera? These are all problems that LED display screens need to face. Next, I will make a brief analysis of several major factors that affect LED display effects (including refresh frequency, gray scale, etc.). The refresh rate of the led display (visual refresh rate) "Visual refresh rate" refers to the rate at which the screen is updated, usually expressed in Hertz (Hz). Generally speaking, the visual refresh rate is above 3,000 Hz, which is a high-performance LED display. The higher the visual refresh rate, the more stable the screen display, and the smaller the visual flicker. The low "visual refresh rate" of the LED display not only affects horizontal stripes when taking pictures and taking photos, but also produces images similar to tens of thousands of light bulbs flashing at the same time, which may cause discomfort to the human eye when watching , and even cause damage to the eyes. Although to the human eye, the visual refresh rate above 60Hz already feels continuous images, but the higher the visual refresh rate, the more stable the displayed image, and the less likely the human eye will feel fatigued. In today's high-quality transparent video wall, in order to obtain more detailed images, such as wonderful playback or close-up photography, high-speed cameras above 1,000 Hz are used for shooting. At this time, for the LED display screen that will also be photographed, it is a big challenge to still be able to present continuous images (no black scanning lines) or continuous color gradation under high-speed shutter. The refresh rate of Voury Zhuohua VW micro-pitch LED display screen is not lower than 3840Hz, and the ingested picture is stable without ripples and black screen, which can effectively solve the smearing and blurring of the image in the process of fast movement, enhance the clarity and contrast of the image, and make the video picture delicate Smooth, long-term viewing is not easy to fatigue; with anti-gamma correction technology and point-by-point brightness correction technology, the dynamic picture display is more real, natural and uniform. gray scale of led display "Gray level" refers to the color levels of various colors between the darkest and brightest colors, which have different changes. Generally speaking, the gray level is above 14 bits (bit), that is, there are at least 16,384 color levels. High performance led display. If the number of gray levels is insufficient, the color level will be insufficient or the gradient color gradation will not be smooth enough, and the color of the video cannot be fully displayed. The LED display effect is greatly reduced. Some low-efficiency LED displays can already detect obvious color patch distribution under the shutter speed of 1/500s. If we increase the shutter speed, such as 1/1,000s or 1/2,000s, the situation will be even worse. obvious. Voury Zhuohua VW series micro-pitch LED display not only has a high brightness of 1200cd/㎡ and a high grayscale of up to 16bit, but more importantly, the product also has the characteristics of low brightness and high grayscale, which guarantees the loss of grayscale when the brightness is reduced The minimum; the gray level is 16bit when the brightness is adjusted to 700cd/㎡, and the gray level is 13bit when the brightness is adjusted to 240cd/㎡; the low brightness and high gray feature makes Voury Zhuohua VW series micro-pitch LED display always able to Perfect and detailed presentation of any pictu e. What affects the refresh rate and gray scale of the led displ ? We know several core components of the LED display, such as LED switching power supply, LED driver chip, LED lamp beads, etc. For the refresh frequency and gray level of the LED display, the LED driver chip directly determines the visual refresh rate of the LED display. , Gray scale performance. Among the current LED driver chips, the most advanced technology is "Scramb LED PWM (S-PWM) technology". S-PWM technology is a technology that improves the traditional pulse width modulation (PWM). into several shorter on-times to increase the overall visual update rate. To further explain, the S-PWM technology built into the new generation of LED driver chips can break up the original method of counting once per frame (LED grain ON→LED grain OFF) into multiple counts on average , and each broken up equal portion can maintain the original On/Off before breaking p S-PWM technology provides different counting modes, so it can increase the image refresh rate up to 64 times. If you switch to S-PWM to increase the image refresh rate, you only need to use a low-level clock (such as 5MHz) to easily increase the visual refresh rate by 64 times, and it can reach more than 4,800Hz. Compared with ordinary video vision, the refresh rate is at least 10 times higher, and it can also avoid the problems of high-frequency electromagnetic interference (EMIissue), overshoot and undersho . The LED display of the S-PWM driver chip is photographed with a high-speed shutter of a digital camera, and there will still be no horizontal black scanning lines and color block distribution (as shown in the figure below). Its visual refresh rate and grayscale performance far surpass the LED display using traditional switch-type driver chi Voury Zhuohua VW series micro-pitch led display adopts high-quality LED driver chip and built-in S-PWM technology, which makes the refresh rate up to 3840Hz and the gray level up to 16bit. When taking pictures under the condition of high-speed shutter, there will be horizontal black scanning after the meeting Distribution of lines and color bloc VW series micro-pitch LED display screen is the outstanding work of Voury Zhuohua's definition of micro-pitch LED display control system. The contrast performance is good, even if the brightness is lowered, the grayscale performance will not be affected, and the color is true. Compared with other screens, the Voury Zhuohua VW series micro-pitch LED screen is comparable to the canvas effect when displaying static scenes, and it is more vivid when displaying dynamic videos. The feeling of being on the scene; and absolutely silent, no noise can be heard in front of or behind the screen during operati . Voury Zhuohua VW series micro-pitch LED screens are at the leading level in the industry in terms of low brightness and high gray, high contrast, true color performance, thinness and ease of use. In addition, this product uses a high-precision modular cabinet to ensure assembly accuracy and display effect, while greatly saving installation time and workload. At the same time, the patented silicone packaging technology adopted by this product has the advantages of high light transmittance, strong anti-vulcanization, anti-UV, anti-blue light, and the advantages of blocking ultraviolet rays and protecting human eyes. product.