23 /Feb / 2023Embedded World 2023
15 /Feb / 2023How to Prevent Electromagnetic Interference for TFT Display?
LCD display TFTs have been on the market for over a decade. It has completely replaced the most traditional CRT display and has become the mainstream market. As a TFT screen manufacturer, Allson now talks about the basics of these LCD monitors from a technical point of view. That is, what determines the brightness of the LCD display TFT today.
The performance of the backlight also has a significant impact on the brightness of the display, which is only determined by the LCD backlight. After the backlight emits light, the light is controlled by the voltage of the front LCD enterprise panel, and the liquid crystal material molecules can allow the light to pass through or block the brightness of the displayed digital image. This process is controlled by an IC chip, which is similar in principle to a shutter in a camera, and can control the amount of light. Camera products usually have a shutter behind the lens. When taking a picture, the shutter opens, allowing the object to form a picture in the negative or photosensitive element. In addition, the liquid crystal panel emits light of balanced brightness from the backlight, which is blocked, controlled by the light of the liquid crystal panel, and imaged by light and shadow.
When you watch a video image on an LCD display TFT or LCD TV, you will find that the light passing through the LCD panel develops not only in the form of the company name and dark, but also in various colors from light to dark. In addition, when we watch animations continuously, the standard is 60 pictures per second, that is, switching between light and dark states 60 times per second. There must be enough pixels in order to display the picture accurately. The structure of the liquid crystal panel should be thin enough. From this social point of view, high-end LCD panels are different from low-end products in these two aspects, which is also one of the reasons for the difference in enterprise management costs.
But because LCD panels can only control light and shadow, this mechanism only works for black and white images. In order to display a color image, a color filter needs to be placed in front of the liquid crystal molecular layer to increase the brightness of the color. Therefore, in addition to the brightness of the backlight, the control of the liquid crystal molecules by the IC chip (operation closing/opening), the quality of the liquid crystal panel itself, the aperture ratio and light transmittance, etc., will have a certain impact on the brightness of the TFT liquid crystal display.