Capacitive touch screen TP structure introduction
At present, the capacitive touch screen on the market mainly has 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 (cover lens), it is also known as the upper layer, and the second letter is the material of the sensor, which also becomes the lower layer. The sensor is connected to the FPC to form the FOG, and the FOG is then combined with the surface material cover lens to become the touch screen.
1) G+F process structure of capacitive touch screen
G+F structure of capacitive touch screen, the first layer is glass, plus a layer of FILM film material. That is, the glass cover + OCA + Film Senser. Glass cover that play a role in protecting the screen and optimize the surface texture, generally use high strength, hardness, good light transmittance tempered glass material. OCA is a solid optical adhesive, good adhesion, light transmittance, used for the glass cover and Film Senser between the lamination. Film Senser is the signal function layer of capacitive screen, which transmits the touch signals and enables the touch function. The scope of application of this structure: suitable for products below 3.5 inches, low-cost solutions.
2) G+F+F process structure of capacitive touch screen
G+F+F process structure of capacitive touch screen, the first layer is also glass, the difference is to add 2 layers of film material. The difference with the G+F structure is to add a layer of Film Senser. G+F+F can achieve multi-touch, and the screen is thinner, the cost is higher than G+F. Film material can not be like glass as 2 sides of the line, it need 2 layers of film to achieve multi-touch requirements.
3) G+G process structure of capacitive touch screen
G+G process structure of capacitive touch screen, that is, glass lens + ITO sensor, the first layer is glass, plus a layer of glass Senser,G+G and G + F structure of the biggest difference is the use of glass Senser. G + G capacitive touch screen has the following features: hard wear-resistant, corrosion-resistant, high light transmittance, smooth control feel, good reliability. As the surface cover is toughened glass, its surface is very hard, the hardness can reach more than 8H, the prevention of scratches is excellent. And the performance is stable, which is currently the main push of the touch screen programme on the market.
PMMA structure of the touch screen is to replace the glass cover with acrylic cover, its advantages are more difficult to break than glass, easy to process, light weight, relatively low cost. The disadvantages are heat sensitive, easy to use in high temperature environment easily deformed, low hardness, easy to scratch.
