News

Do you know what the TP structure of capacitive touch screen is?

capacitive touch screen TP structure introduction:
Currently, the capacitive touch screens on the market mainly have the following six structures: "G+G, G+F, G+F+F, PMMA+G, PMMA+F, PMMA+F+F". g or PMMA represents the surface material of the touch screen (covering the lens), which is also called the upper layer, and the second letter is the material of the sensor, which is the bottom layer. The sensor is connected to the FPC to form a fog, and then combined with a surface material covering the lens to form a touch screen.

1) G+F process structure of capacitive touch screen

capacitive touch screen structure, the first layer is glass, plus a layer of film material. That is, glass cover + OCA + thin film sensor. The glass cover plays a role in protecting the screen and optimizing the surface texture. It is generally made of tempered glass material with high strength, high hardness and good light transmittance. OCA is a solid optical adhesive with good adhesion and light transmittance. It is used for lamination between glass covers and thin film sensors. The thin film sensor is the signal function layer of the capacitive screen, which transmits touch signals and realizes the touch function. Application range of this structure: Suitable for low-cost products below 3.5 inches.

2) G+F+F process structure of capacitive touch screen

The G+F+F process structure of the capacitive touch screen, the first layer is also glass, the difference is that two layers of thin film materials are added. The difference from the G+F structure is the addition of a layer of film sensor. G+F+F can achieve multi-touch, the screen is thinner, and the cost is higher than G+F. The film material cannot be used as lines on both sides like glass. It requires two layers of film to achieve multi-contact requirements.

3) G+G process structure of capacitive touch screen

The G+G process structure of the capacitive touch screen is glass lens + ITO sensor. The first layer is glass, plus a layer of glass sensor. The biggest difference between G+G and G+F structures is the use of glass sensors. G+G capacitive touch screen has the following characteristics: hard wear resistance, corrosion resistance, high light transmittance, smooth control feeling, and good reliability. Since the surface is covered with tempered glass, its surface is very hard and its hardness can reach more than 8 hours, which is excellent in preventing scratches. And the performance is stable, which is currently the market that mainly drives touch screen programs.

The structure of the touch screen uses acrylic resin instead of the glass cover. Its advantages are that it is harder to break than glass, easy to process, light weight, and relatively low cost. The disadvantages are that it is heat sensitive, easy to deform when used in high temperature environments, has low hardness, and is easy to scratch.

To sum up the structure of the capacitive touch screen, the capacitive touch screen can be simply regarded as a screen composed of four layers of composite screens: the outermost layer is a glass protective layer, followed by a conductive layer, and the third layer is non-conductive glass Screen, the fourth innermost layer is also a conductive layer. The innermost conductive layer is a shielding layer, which plays a role in shielding internal electrical signals. The middle conductive layer is a key part of the entire touch screen. There are direct leads on the four corners or four sides, which are responsible for detecting the position of the touch point.