We often hear what the grayscale of the LED display is, but few people know what the grayscale of the LED display means. There is a lot of content here, so let’s take a look at it briefly.
First of all, let’s take a look at the light-emitting method of the LED display:
The luminous color and luminous efficiency of LED are related to the material and process of making LED. At present, there are three kinds of red, green and blue (R, G, B) widely used. Due to the low operating voltage of the LED (only 1.5-3V), it can actively emit light and have a certain brightness, and the brightness can be adjusted by voltage (or current), and it is shock-resistant, vibration-resistant, and has a long life (up to 100,000 hours). In large-scale display devices, there is no other display method that can match the LED display method.
Let’s take a look at the types of light-emitting LED displays:
A display made by putting red and green LEDs together as one pixel is called a two-color screen or a color screen; a display made by putting red, green, and blue LED tubes together as one pixel is called a three-color screen or a full-color screen.
The pixel size of the indoor LED display screen is generally 1.5-6 mm, and several LED tube cores that can produce different primary colors are often packaged into one body. The pixel size of the outdoor LED display screen is mostly 3-20 mm. A pixel is composed of several single-color LEDs. The common finished product is called a pixel tube. A two-color pixel tube is generally composed of 3 red and 2 green, and a three-color pixel tube is composed of 2 red, 1 green and 1 blue.
Regardless of using LEDs to make single-color, two-color or three-color screens, the luminance of each LED that constitutes a pixel must be adjustable to display an image, and the fineness of the adjustment is the gray level of the display screen.
The higher the gray level, the more delicate the displayed image, the richer the color, and the more complex the corresponding display control system. Generally, the color transition of the 256-level grayscale image is very soft, while the color transition line of the 16-level grayscale image is very obvious. Therefore, color LED displays are currently required to be made into 256-level grayscale.
In a conference room, no one is going to be very close to seeing the whole picture. Just like we watch TV, no one wants to stand in a very close place to watch TV, which in itself is great damage to the eyes. In the previous meeting rooms, most of them used projectors and curtains to realize the picture display. Generally, the projector is far away from the screen, and if it is projected on the screen, the brightness of the picture will be greatly reduced, and the viewing effect is average.
Even with an ultra-short-throw projector, the projected effect cannot reach the effect displayed by small-pitch LEDs, not to mention that ultra-short-throw projectors are mainly used to project small images. But LED is different. It has a large viewing angle, high color reproduction, high brightness, and high grayscale. It can be spliced in any size, and even made into different shapes. There are various installation methods and long service life.