Since the appearance of led displays, most outdoor led displays have adopted white LED packaging devices (white lights). With the development of led displays, in recent years, in addition to white lights, black LED packaging devices (black lights) have increasingly appeared on the market.
Panavisual RP series
Why are there few outdoor SMD black light rental products on the market?
1. The price of SMD black light is relatively high, which is 2-3 times that of SMD white light. Customers are generally sensitive to the price of the product, and the price is too high, which is often unacceptable.
2. Customers always think that outdoor rental products need high brightness; At present, the mainstream outdoor rental products in the market are white lights. Customers are used to thinking that black lights should meet the outdoor rental needs, and the brightness should be as high as white lights.
3. Customers have used SMD white light outdoor rental products for a long time, and know little about SMD black light; Little is known about whether the brightness of black light products used in outdoor leasing activities can meet the requirements for outdoor use, and little is known about the display effect of black light products used in outdoor activities.
Why is it better to use SMD black light for outdoor lease?
1. Contrast can determine the image definition more than brightness;
Must the led display have such high brightness? The reason is that to improve the brightness of led display screen is essentially to increase the visibility of screen pictures, videos and other content for consumers. Research shows that the human eye feels more about color than about light and dark. The visual cells in the human retina are composed of cone cells and column cells. Because each cone cell is connected to an optic nerve terminal, it has high resolution and can distinguish details and colors; However, multiple columnar cells are connected to an optic nerve terminal, so the resolution is low and only the contour of the figure can be distinguished. Although the human eye has a wide range of general perception of brightness, when the human eye adapts to a certain ambient brightness, its sense range will be limited. At this time, the cone cells responsible for color inspection play a major role.
SMD black light has high contrast, and the contrast of outdoor products is more important than brightness. Through the analysis and measurement of the optical performance parameters of led display screen, we can objectively evaluate the video display effect of led display screen. The contrast determines the clarity of the display screen, which has a great impact on the display effect; The higher the contrast, the stronger and more vivid the displayed image.
1) Comparison between outdoor SMD white light and outdoor SMD black light:
The left picture shows 5000 contrast, and the right picture shows 3000 contrast
The highest contrast refers to the ratio of the maximum brightness of the display screen measured under a certain ambient illumination to the background brightness; The higher the background brightness of outdoor products is, the worse the display effect is. SMD white light will improve the background brightness, and the contrast of relative white light will be lower. High contrast means relatively high brightness and the gorgeous degree of colors).
As shown in the above figure: in the outdoor environment, the white light has a higher background brightness than the white display screen because of its light surface; Black light The background brightness of the display screen is low because the light surface is black.
3) The background luminance ratio of the black lamp for outdoor rental products is generally 5000:1; The background brightness ratio of outdoor white light is generally 3000:1. However, in the outdoor environment, due to the strong ambient light, the background brightness of the display screen is higher than that tested, and the relative contrast will be lower.
4) The background brightness is generated by the external light reflected by the panel and the luminous tube of the led display screen, that is, the measured background brightness is determined by the reflection coefficient of the panel and the luminous tube.
Firstly, the reflection of the panel is analyzed. The larger the reflection coefficient of the panel is, the larger the measured background brightness value is, and the smaller the contrast value is. Therefore, to improve the calculation value of contrast, the reflection coefficient of the panel should be reduced as much as possible.
The simplest way to reduce the reflection coefficient is to paint a layer of light absorbing material on the background panel to reduce the reflected light. In order to reduce the background brightness to a greater extent, small grooves or patterns can be carved on the panel, as shown in the simplified diagram below:
5) In addition to high contrast, black light also brings another higher quality performance, which is non reflective. Because the PPA bracket in the black LED lamp bead is black, because black does not reflect light, that is, it has no reflective ability, so the light shining on the black object is converted into other energy (such as heat energy), so even when there is stray light, the black PPA bracket will absorb all of it, no longer reflect the stray light, thus reducing the interference of stray light, so that the color is more real, no cross color The phenomenon of tailing and mutual interference of various colors makes colors more pure, clear and lifelike. Especially for LED stage background screen, the display effect of LED stage background screen will be seriously affected due to the large number of projector colors and interlaced light and shadow in the stage environment. In addition to the fact that the black light itself does not reflect light, Panavisual also uses the surface atomization technology to make the light diffuse. The display screen can still clearly see the image on the display screen in the stage environment with severe reflection, so it can avoid the interference of light from various light sources on the stage, thus increasing the black screen effect of the led display screen and not being affected by the brightness of the external environment, The led display screen made of black light can always keep the brightness level of the display screen clear and bright. At present, black PPA material is widely used for painting ink on the surface of LED and LED. As shown below:
Advantages: high brightness, low price and high market share
Disadvantages: high reflectivity of cup and PPA edge affects the contrast of display screen
Advantages: low emissivity improves the contrast of the whole screen
Disadvantages: low brightness and slightly higher price compared with surface inking
2. SMD black light display effect is more delicate.
As shown in the above figure, the higher the contrast, the more delicate the display effect under the same brightness; The higher the contrast of the same color, the better the excessive gray scale display;
3. It can realize real indoor and outdoor dual-use.
The brightness of Panavisual's outdoor black LED screen products reaches 4000nit, which can fully meet the use requirements of various outdoor places. With Panavisual's original gray compensation technology, the brightness gray scale will not change when it is used indoors; While for the 3000-4500nit conventional outdoor products of other companies in the industry, when the brightness needs to be reduced to about 10000nit indoor, the loss of gray scale reduction is relatively large, and the fineness of indoor display and the authenticity of color restoration will be much worse.
The following is the contrast effect of conventional white light (left picture) (4500nit) and Panavisual's outdoor black LED screen (4000nit), and the indoor use after the brightness is reduced to 1200nit respectively. The outdoor black LED light, together with Panavisual's gray compensation technology, can truly achieve the effect of universal use inside and outside the home, and achieve a multi-purpose screen.
4. Panavisual's outdoor black LED rental solution
In view of many advantages of outdoor black lights, Panavisual launched RP series(Phantom series) leased LED screen products for different application requirements. Maximize the value of products purchased for customers.