LCD Screens Divided from Polarizers (Segment Mode)
- Jun 05, 2018 -

                       

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The LCD screen is distinguished from the polarizer (segment code): it can be divided into: HT, HTN, STN, FSTN, VA, etc.


    It is currently one of the most widely used display technologies and components. However, in the actual industry chain, each company or each engineer also has different technical insights on the same issues. This is often because such different opinions are likely to cause disputes and affect the cooperation and production of the cooperative companies and manufacturers.


       The structure of STN and HTN LCD is composed of upper polarizer, ITO glass, liquid crystal, ITO glass, and lower polarizer. Other structures such as epoxy resin to form a closed cell, and beading process to control the height of liquid crystal cell Not repeat them. Usually LCD manufacturers will provide the drive circuit formed by the driver IC and voltage divider resistor network, plus the necessary backlight and mechanical structure, called the LCD module, or LCM. A large number of application engineers only understand the interface of the LCM drive circuit, and ignore the principle of liquid crystal display. At the same time, the LCD manufacturers are also very clingy to the LCD production process and detection methods, and their attention to the drive circuit is insufficient. In this way, when encountering uncommon, hidden, faulty phenomena, they are often considered to be misunderstandings of the other party, trying to persuade the other party and failing to find the root cause of the failure and failing to provide solutions.


Polarizer


       The rapid development and revolutionary nature of modern physics has laid a solid foundation for the ever-changing electronic components. However, people are often consciously or unwittingly skipping the basic theories and fundamental physical phenomena and experiments of modern physics when they are enjoying the progress of science and technology from the new functions of electronic components to the familiar and seemingly natural sense.


       From a physical point of view, sunlight diffuses into the earth's atmosphere and becomes polarized in all directions. The polarizer passes light polarized in one direction and filters out the remaining light. The light entering the LCD cell will thus and only be polarized in the same direction. The upper and lower glass cells of the liquid crystal cell are respectively distributed with corresponding ITO traces, and corresponding electrodes are formed on the liquid crystals. Liquid crystals are organic long rod molecules that have both electrical polarity and optical anisotropy. If a voltage difference is established across the electrodes, the liquid crystal molecules deflect, and the light of a specific polarization direction reaches the lower polarizer through the liquid crystal molecules and folds back into the viewer's eyes. The observer sees the relevant characters or patterns on the LCD. If the voltage difference applied on the electrode is not enough, the deflection angle of the liquid crystal molecules is not enough, thereby affecting the amount of the returned light, and finally the relevant characters or patterns on the LCD seen by the observer become insufficient display and ghost images are formed.


       From the perspective of the LCD panel factory, the STN and HTN LCDs have characteristics relating to liquid crystal materials, process limitations such as wiper film angles, and difficulties in understanding due to their professionalism and confidentiality of the production process. Thus, the industry can specify the specifications for LCD users to view in the direction of view - common six o'clock and twelve o'clock, drive methods - such as 1/4 duty and 1/3bias. Duty refers to the duty cycle of the drive waveform. From the oscilloscope, the horizontal axis is the time axis. Bias refers to the driving waveform bias voltage. From the oscilloscope, the vertical axis is the voltage amplitude.


        The general driving method - such as 1/4 duty and 1/3bias, will use the 1621 driver IC to write drive level.




Jingtuo is a subsidiary of Suzhou Kaipu Microelectronics Co., Ltd., which owns the brand of LCD screens. The company's ten-year operations have always adhered to the business philosophy of "survive by quality, seek development by innovation" and honesty, and mainly supply single-chip solutions. Design and development, as well as TN/HTN/STN/FSTN liquid crystal displays, COG/COB liquid crystal modules and various backlight products, occupying fields such as instruments, meters, POS systems, telephones, access control, computers, communications, televisions, and smart home appliances. Larger market share.