Each pixel of the LCD liquid crystal screen is composed of the following parts: A column of liquid crystal molecular layers suspended between two transparent electrodes (indium tin oxide), and there will be two polarization directions perpendicular to each other on the outside of the two sides. Filter disc. If it is a liquid crystal without electrodes, when light passes through one of the polarizing filters, its polarization direction will be completely perpendicular to the second polarizer, so it will be completely blocked. However, if the polarization direction of the light passing through one polarization filter is rotated by the liquid crystal, it can pass through another polarization filter again.
Some LCD screens will turn black under the action of alternating current. The alternating current destroys the spiral effect of their liquid crystals. After the current is turned off, the liquid crystal display will become brighter or transparent. This type of liquid crystal display is common in Above the laptop and flat LCD screen. The other type is often used on high-quality LCD screens or large LCD TVs. When the power is turned off, the LCD screen is opaque.
For the first power, the LCD screen will use the multiplexing method. In the multiplexing mode, the electrodes at one end are connected in groups, the electrodes in each group are connected to a power source, and the electrodes at the other end are also connected in groups. Each group is connected to the other end of the power supply. The grouping design ensures that each pixel is controlled by an independent power supply. The electronic device or the software driving the electronic device can control the display of the pixel by controlling the on/off serial of the power supply. Effect.
The indicators for testing LCD screens include the following important aspects: display size, response time (synchronization rate), array type (active and passive), viewing angle, color supported by the screen, brightness and contrast, resolution, and The aspect ratio of the screen, and the input interface (such as visual interface and video display array).
