LCD Touch screen For iPhone 6S

                                                   Some Analysis on the Principles and Basic Knowledge of Touch Screen

There are currently several types of touch screens, they are: resistive (double layer), surface capacitive and inductive capacitive, surface acoustic wave, infrared, and bending wave, active digital converter and optical imaging . They can be divided into two types, one type requires ITO, such as the first three touch screens, and the other type does not require ITO in the structure, such as the latter types of screens.

Touch screens can be seen everywhere around us. In the field of personal portable devices such as PDAs, touch screens save space and are easy to carry, and have better human-computer interaction.
There are currently several types of touch screens, they are: resistive (double layer), surface capacitive and inductive capacitive, surface acoustic wave, infrared, and bending wave, active digital converter and optical imaging . They can be divided into two types, one type requires ITO, such as the first three touch screens, and the other type does not require ITO in the structure, such as the latter types of screens. Currently on the market, resistive touch screens and capacitive touch screens using ITO materials are the most widely used.
Resistive touch screen
ITO is the English abbreviation of indium tin oxide, which is a transparent conductor. The properties of this substance can be tuned by adjusting the ratio of indium to tin, deposition method, degree of oxidation, and grain size. Thin ITO materials have good transparency but high impedance; thick ITO materials have low impedance but poor transparency. When depositing on PET polyester film, the reaction temperature should drop below 150 degrees, which will lead to incomplete oxidation of ITO. In the subsequent application, ITO will be exposed to air or air spacer, and its unit area resistance will decrease due to self-oxidation. Change of time. This makes resistive touch screens require frequent calibration.

capacitive touch screen
Capacitive touch screens also need to use ITO materials, and its low power consumption and long life, but the higher cost has made it less popular before. The friendly human-machine interface and smooth operation performance provided by Apple's iPhone have made capacitive touch screens popular in the market, and various capacitive touch screen products have come out one after another. And with the advancement of technology and mass production, its cost continues to decline, and it begins to show the trend of gradually replacing resistive touch screens.