Capacitive touch screen structure is mainly in the glass screen with a layer of transparent film layer, and then in the conductor layer plus a protective glass, double glass design can completely protect the conductor layer and sensor. The same time as the above-
Capacitive touch screen in the touch screen are coated with long and narrow sides of the electrode, in the conductor to form a low voltage AC electric field. In touching the screen, due to the human body electric field, between the finger and the conductor layer will form a coupling capacitor, Capacitive Touch Screen the four sides of the electrode current will flow to the contact, and the current strength and the finger to the electrode is proportional to the distance, after the touch screen controller Will calculate the proportion of current and strength, accurate calculation of the location of the touch point. Capacitive touch screen double glass not only protects the conductor and the sensor, more effectively prevent the external environment factors affect the touch screen, Capacitive Touch Screen even if the screen stained with dirt, dust or grease, capacitive touch screen can still accurately calculate the touch position.
Since the capacitance varies with the contact area and the dielectric of the medium, the stability is poor and tends to drift. This kind of touch screen is suitable for the debugging phase of system development.
Capacitive touch screen principle
Is the use of the body's current sensing work. Capacitive touch screen is a four-layer composite glass screen, the inner surface of the glass screen and the interlayer are coated with a layer of ITO, the outermost layer is a thin layer of siliceous glass protective layer, sandwich ITO coating as a face, Capacitive Touch Screen four corners Four electrodes, inner ITO for the shield to ensure a good working environment.
Capacitive touch screen advantages are:
1. Operation novelty. Capacitive touch screen support multi-touch, more intuitive operation, more fun.
It is not easy to touch. As the capacitive touch screen needs to be sensed to the human body current, only the human body to its operation, with other objects touch will not be corresponding, so the basic to avoid the possibility of false touch.
3. High durability. Compared with the resistive touch screen, Capacitive Touch Screen capacitive touch screen in the dust, water, wear and other aspects of a better performance.
As the current legitimate red touch screen technology, capacitive touch screen, although the interface with gorgeous, multi-touch, only the human body and other advantages
Capacitive touch screen manufacturing principle: the life of the special sensor on the screen charge movement. These charges are transferred from the touch screen to the touch IC through the four-conductor wires to analyze the current positioning formed by the charge movement on its pins. Capacitive Touch Screen Relative to the market has been popular in the resistance of the touch screen, the capacitive screen of the technical requirements are relatively high, the existing concept of mix, the accuracy has reached 99%, the material also has a completely scratch-resistant glass material, and in the To a certain extent, both the effect of eye protection, on the display, damage, durability, light transmittance, sensitivity, accuracy and other practical prospects, capacitive screen also has its own unique innovation, although the high cost, but Still become the dominant application technology in today's market.
Forward-looking Industry Research Institute data show that capacitive touch screen in 2009 accounted for about 29% of the entire touch screen market, resistive touch screen accounted for 68%, and with the concept of continuous expansion of the concept of capacitive screen, and intelligent areas of electronic digital products on the future planning co- 2012 capacitive touch screen has accounted for 52%, resistive touch screen is down to 44% of the market share. Because capacitive touch screen in quality, performance, user experience and other aspects of superiority, coupled with the improvement of technical level and yield gradually increased, it was predicted that the future capacitive screen market share will reach 100%, completely replace the resistive touch screen market status.