Front Screen Glass lens for iphone XR

                                                                                    Capacitive touch screen structure
     The structure of the capacitive touch screen is mainly to coat a transparent film body layer on the glass screen, and then add a protective glass outside the conductor layer. The double glass design can completely protect the conductor layer and the sensor. 

The capacitive touch screen is coated with long and narrow electrodes on the four sides of the touch screen, forming a low-voltage AC electric field in the conductor. When touching the screen, due to the electric field of the human body, a coupling capacitance will be formed between the finger and the conductor layer, and the current from the electrodes on the four sides will flow to the contacts, and the current strength is proportional to the distance from the finger to the electrode. The controller behind the touch screen is then It will calculate the proportion and strength of the current, and accurately calculate the position of the touch point. The double glass of the capacitive touch screen can not only protect the conductors and sensors, but also effectively prevent external environmental factors from affecting the touch screen. Even if the screen is stained with dirt, dust or oil stains, the capacitive touch screen can still accurately calculate the touch position.

Since the capacitance varies with the contact area and the dielectric of the medium, its stability is poor, and drift often occurs. This kind of touch screen is suitable for the debugging stage of system development.