Small pixel led display achieve high greyscale low brightnes

Small pixel led display achieve high greyscale low brightnes

In the field of indoor small pixel led display, the traditional LED display is mostly used for advertising display or information display. With the gradual maturity of fine pixel LED display products, the application field of narrow pixel LED display screens has rapidly expanded. Commercial display, conference display, command and control, and dispatch monitoring, which are covered by the indoor display, may become the market for small-pitch LEDs. This market may have a scale of tens of billions a year in the future.

    Faced with the temptation of the market, LED display manufacturers flocked. The major LED display listed companies have successively released their small pitch LED screen products: Liard's large-size "LED TV", Chau Ming Technology's "LED Super TV", Lianjian Optoelectronics "micro-closed LED display", etc. Although the names are different, they are essentially small-pitch LED displays. In addition to these listed companies, companies that are optimistic about the indoor small-pitch LED market and ready to test water are not rare in the industry.

    However, is the current specification of small-pitch LED displays suitable for indoor applications? Is it easy to move the LED display directly from the outside to the inside? The application environment of the product has changed a lot. The LED screen manufacturers who are hot-headed need to think about whether the design of the LED display product itself needs to be based on Change in the application environment?

    One of the most striking differences between indoor and outdoor applications is the change in ambient light. When the LED display is used outdoors, the intensity of sunlight during the day is very high. Therefore, the brightness of the outdoor LED display needs to be highlighted, bright, and super bright! The higher the brightness of the display, the higher the technical specifications of the display.

    However, after the small-pitch LED display enters the room, the application conditions have changed a lot: first, the indoor environment brightness is greatly reduced; secondly, compared with the traditional users of the LED display, the small-pitch LED products are also rapidly and greatly The viewing distance between the display and the user is zoomed in; another significant feature is that the users of the indoor conference, command and control, and monitoring room will continue to pay attention to the screen for a long time.

    Under the dark environment of the human eye, the high-intensity small-pitch LED display screen is closely and long-time. The high brightness of the LED is often irritating, and even causes sore eyes, tears and decreased vision. Therefore, the brightness of the LED display is too high, which will bring visual fatigue to the users of indoor applications, and even serious damage may cause irreparable human eye damage! It can be said that the brightness of the small-pitch LED display is definitely not as high as possible, and its brightness must be lowered.

    So what is the appropriate brightness reduction of the LED display?

    First, let's refer to the brightness range of various indoor display products in the indoor application environment. The brightness range of home TV sets is 350 cd/m2-500 cd/m2; the brightness range of DLP video wall is 250 cd/m2-400 cd/m2; the brightness range of LCD video wall is 450 cd/m2-700 cd/m2 .

    Because the human eye's perception of brightness is relative, the display with different illumination technologies will give different perceptions of brightness to the human eye. After a lot of testing, we believe that the brightness range of the LED display is controlled at 100 cd/m2-300 cd/m2. In this brightness range, the human eye feels more comfortable.

    And we look at the current small-pitch LED display specifications on the market, it is not difficult to find that there is a big gap between the existing display brightness and the actual application brightness. Take the listed company in Beijing as an example. The company's official website clearly indicates the specifications of LED small-pitch products, and the brightness value is greater than 1200 cd/m2, which is much higher than the comfort range of 100 cd/m2-300 cd/m2.

    So can you directly solve the problem by directly adjusting the brightness of the display? The answer is not that simple. Because the conventional LED display has the characteristics of low brightness and low gray, that is to say, the brightness of the display is reduced and the grayscale of the picture is lost.

    We have carried out a large number of actual tests on small-pitch LED displays from multiple manufacturers and found that when the brightness of the display is reduced to 500 cd/m2 or even from 600 cd/m2, the picture has already begun to appear more obvious gray. Degree loss phenomenon. And with the further reduction in brightness, the gradation loss is also becoming more and more serious. When the brightness is reduced to less than 200 cd/m2, most of the display screens have a large loss of gradation, and the picture quality is almost "unsightly".

Untitled -1.jpg

    Therefore, if a small-pitch LED display with a nominal brightness greater than 1200 cd/m2 is directly applied to the indoor environment, the result is only two: either high brightness damages the user's eyes, or reduces brightness while losing grayscale loss quality. And neither of these is what the user wants.

    To solve this problem, we must require our display manufacturers to upgrade the current small-pitch display, and develop a "low-bright, high-gray" small-pitch LED display. The so-called low-light and high-ash is specifically explained as: when the brightness range of the small-pitch LED display is in the range of 100 cd/m2-300 cd/m2, the gray level of the display screen is not lost, or the degree of gray loss is difficult to detect in the human eye. In the range.

    The LED display has to be characterized by low brightness and high brightness and is related to the chip, drive, control and other aspects of the display screen. Therefore, display manufacturers need to concentrate on research and development to make a display that is truly suitable for indoor environment applications. And we are also pleased to find that there are low-gloss, high-gray, small-pitch LED displays on the market. Among the products we tested, there are very small-pitch products that perform very well. When the brightness reaches 100 cd/m2 or less, the loss of grayscale is indistinguishable to the naked eye, and the image quality is very good.

    Therefore, low-light and high-gray is a threshold that LED display manufacturers must cross to enter indoor display applications. Low-light and high-ash will be one of the key factors to distinguish the quality of small-pitch LED display products. For small-pitch products, the LED display will no longer be compared to who has higher brightness, but who is less bright. Compared to the display screen of anyone who can reduce the brightness without losing grayscale and image quality. In other words, only the low-gloss, high-gray small-pitch LED display is a good product that meets the user's requirements and has competitive strength.

    Indoor small-pitch LED is an emerging market, and it is bound to face the lack of current industry standards, which has caused many manufacturers to blindly launch products that do not meet the actual requirements. The market will follow the rules of the survival of the fittest, and users will certainly be able to make the right choice. Low light and high gray is undoubtedly the first threshold for small pixel led display -pitch LED display to enter the room.