- Jul 25, 2018 -
Whether it's a laptop or a desktop system, the LCD display is a layered structure of different parts. The last layer on the last layer is a backlight layer composed of a fluorescent material that emits light. The light emitted by the backlight layer enters the liquid crystal layer containing thousands of crystal droplets after passing through the first polarizing filter layer. The crystal droplets in the liquid crystal layer are all contained in a small cell structure, and one or more cells constitute one pixel on the screen. When the electrodes in the LCD generate an electric field, the liquid crystal molecules are distorted, and the light passing through them is regularly refracted, and then filtered through the second layer of the filter layer to be displayed on the screen.
For simple monochrome LCD displays, such as those used in handheld computers, the above structure is sufficient. But for the more complex color displays used in laptops, there is also a need for a color filter layer that specifically handles color displays. Generally, in a color LCD panel, each pixel is composed of three liquid crystal cells, each of which has a red, green, or blue filter in front of each cell. This way, different colors can be displayed on the screen by light from different cells. Almost all LCDs used in notebook or desktop systems use thin film transistors (TFTs) to activate cells in the liquid crystal layer. TFT LCD technology can display sharper, brighter images. LCDs in the 1960s and 1970s were low-speed, inefficient, and low-contrast. Although they can display clear text, they often produce shadows when displaying images quickly, affecting the display of video. It is only used in handheld computers, pagers or mobile phones that require black and white display.
Affected by the actual number of cells in the LCD liquid crystal layer, LCD displays generally only provide a fixed display resolution. If the user needs to increase the resolution of the 800X600 to 1024X768, the analog resolution can only be achieved with the help of specific software.
Like traditional CRT displays, LCDs used in desktop systems are also designed to receive waveform analog signals rather than digital pulse signals generated directly by the PC. This is mainly because most standard graphics cards in desktop systems still transmit video information from the original digital signal to the analog signal and then to the display. Although the LCD of the desktop system is designed to receive analog signals, the LCD itself can only process digital information, so after receiving the analog signal from the graphics card, the LCD needs to restore the analog signal to a digital signal for processing. In order to solve the display deficiencies caused by the above problems, the latest desktop LCD uses a special digital card with a digital connector to directly transmit digital signals to the LCD display.
As LCD technology continues to mature and evolve, the size of display screens is gradually increasing. Traditional laptops use an 8-inch (diagonal) fixed-size LCD display, and TFT-based desktop LCDs can support 14 to 18-inch display panels. Because the manufacturer determines the size of the LCD according to the size of the actual viewable area, rather than the size of the picture tube as the CRT, the size of the 15-inch LCD is generally equivalent to the size of the traditional 17-inch color display.