According to the processing sequence, the TFT-LCD liquid crystal screen is divided into: array process, box molding process and modular process. In this article, we will introduce the first array process in detail TFT Display.
The array process is similar to the process of regularly fabricating TFT devices, pixels and other patterns on a glass substrate through a semiconductor process. The array process includes cleaning process, CVD film formation technology, sputtering film formation technology, photoresist or photoresist (PR) coating, development stripping technology, exposure technology, wet etching technology, dry etching technology, etc., Finally, 4 to 5 layers of thin film patterns are formed on the glass substrate.
Clean the glass substrate first, and then form a thin film (metal sputtering mode, non-metal CVD mode); after the film is formed, coat PR on the substrate, expose with a mask, transfer the required pattern from the mask to the PR, and expose the PR Partially rinse, and the remaining PR is the desired pattern; then, the etching process (metal is generally wet etched, and non-metal is generally dry etched) to remove the film without PR protection, leaving the desired film pattern; then, Peel off the public relations, leave the array process and finally perform annealing treatment as required to check the array process for the entire project TFT LCD module.
1. Display size: The display size of TFTLCD refers to the diagonal length of the actual visible area, in inches, abbreviated as inches (1 inch = 2.54 cm).
2. Aspect ratio: The aspect ratio is the ratio of the length to the width of the visible area of the TFTLCD, also known as the screen ratio. The aspect ratio of TFT-LCD is mainly 4:3, 5:4, 16:10 and 16:9. The ratio of 16:9 is closer to the golden ratio, which is more comfortable to the human eye. In the design of TFTLCD products, H (horizontal) usually means length, and V (vertical) means width.
3. Effective display area: The effective display area refers to the total screen area that TFTLCD can display. Knowing the display size and aspect ratio of the TFT-LCD, the specific length and width of the effective display area can be calculated using Pythagoras`s law.
4. Number of pixels: The resolution of TFTLCD indicates the number of luminous points that can be used for image display in the effective display area. The light-emitting points in TFTLCD are called pixels. The resolution is usually expressed in the form of multiplication, such as a resolution of 1024×768, where 1024 represents the number of pixels displayed in the horizontal direction of the effective display area, and 768 represents the number of pixels displayed in the vertical direction. The resolution reflects the total number of pixels in the effective display area. The higher the resolution, the higher the resolution of the picture. Generally, the human eye is more sensitive to the number of pixels in the vertical direction LCD Module. The higher the vertical resolution, the higher the clarity of the picture.
5. Pixel pitch: The pixel pitch is the distance between two adjacent pixels in the effective display area of the TFTLCD, that is, the minimum length of the pixel repeating unit. The pitch of TFTLCD is fixed, and the pitch is calculated by dividing the panel size by the resolution. The fineness of the picture is determined by the pixel pitch. The smaller the pixel pitch, the finer the image. A more accurate index of picture fineness is the PPI (pixels per inch) value or dpi (dots per inch) value, which is the number of pixels in a unit size. The high-precision TFTLCD display has a high PPI value.
6. Power consumption: The power consumption of TFTLCD is mainly the power consumption of the backlight, which accounts for about 90%. Reducing power consumption is the focus of the future development of TFT-LCD.
7. Lifetime: The service life of TFTLCD mainly depends on the service life of the light source, and the unit is hour. Generally speaking, there is no problem using TFTLCD for tens of thousands of hours. If used for 5 hours a day, it can be used for about 10 years. The service life of TFT-LCD is also called mean time between failures (MTBF), which is calculated based on practical experiments with high temperature and high humidity.
The array technology and basic parameters of the LCD screen?
2022 01/06