Most of the resistive touch screen, general film with commonly used cell phone film can be, Iphone4 is capacitive, capacitive screen is a four-layer composite glass screen, glass screen, the inner surface and the sandwich each coated with a layer of ITO, the outermost layer is only 0.0015mm thick silica glass protective layer, the sandwich ITO coating for the work surface, the four corners of the four electrodes, the inner layer of ITO for the screen to ensure that the working environment. When the user touches the capacitive screen, due to the human body electric field, the user's finger and the working surface to form a coupling capacitance, because the working surface is connected to a high-frequency signal, so the finger absorbs a very small current, this current flows from the electrodes on the four corners of the screen, and theoretically flow through the four electrodes of the current with the fingertip to the four corners of the distance proportional to the controller through the proportion of the four currents of the precision calculations, to derive the Position. ------ITO is an oxide with high conductivity and light transmission ability.
Precautions nothing specific to the Iphone4 film no problem, use caution when broken, afraid of falling!
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