The touch screen brings a lot of convenience to people’s work and life, and its applications in the market are also very popular, which can be seen in all fields.
Resistive touch screen vs Capacitive touch screen: What’s the difference between capacitive and resistive touch screens?
What is a resistive touch screen?
1) The resistive touch screen is a kind of sensor, which is basically a structure of thin-film and glass. The adjacent side of thin-film and glass is coated with ITO (nano indium tin oxide). ITO has good electrical conductivity and transparency. When touching the ITO in the lower layer of the film, it will touch the ITO in the upper layer of the glass, and send corresponding electrical signals through the sensor, which will be sent to the processor through the conversion circuit and converted into X and Y values on the screen through calculation, and the action of clicking will be completed and presented on the screen.
2) resistive touch screen works: mainly through pressure induction principle to realize the operation and control of screen contents, this kind of touch screen body part is a very cooperate with multi-layer composite membrane and display surface, including the first layer of glass or bottom of organic glass, the second layer of isolation layer, the third layer for multivariate resin surface, the surface is coated with a layer of the transparent conductive layer, the above with a layer of surface hardening treatment, then smooth scratch-resistant plastic layer. Generally speaking, the capacitive touch screen supports multi-touch human-computer interaction, while ordinary resistive touch screens can only touch a single point.
3) Resistive touch screen: all layers of the screen are in contact with pressure. Fingers (even with gloves on), fingernails, and stylus can be used for the operation. Stylus support is important in The Asian market, where gesture and word recognition are valued. Resistive touch screen, commonly known as “soft screen”, is mostly used in Windows Mobile phones; Capacitive touch screens, commonly known as’ hard screens, ‘are used in devices like the iPhone and G1.
What is a capacitive touch screen?
1)The capacitive touch screen is a transparent layer of special conductive metal on the surface of the glass. When the finger touches the metal layer, the capacitance of the contact changes, causing the frequency of the oscillator connected to it to change. By measuring the frequency change, the position of the touch can be determined to obtain information. Because capacitance varies with temperature, humidity, or ground condition, its stability is poor and drift phenomenon often occurs.
advantages of capacitive touch screen: Capacitive touch screen is by touch, change the capacitance by changing the electrolyte capacitor, touch, electrolyte change, capacitance change, so mobile phones have a reaction, such as mobile phones don’t match, the screen is not easy to scratch, and the most practical identification method is: use two fingers hold the capacitive touch screen on the phone a picture at the same time, the fingers on both sides to open or close, images will be enlarged or reduced, and this point, resistive touch screens.
2) Working Principle of capacitive Touch screen: The CTP Capacity Touch Panel USES the current induction of the human body to work.The capacitive screen is a four-layer composite glass screen, the inner surface of the glass screen and the interlayer are each coated with ITO (nanometer indium tin oxide), the outermost layer is a silica glass protective layer only 0.0015mm thick, the interlayer ITO coating is used as the working face, four electrodes are derived from the four corners, and the inner ITO layer is used as the screen layer to ensure the working environment.
3) Capacitive touch screen: The smallest contact from the surface of the charged finger can activate the capacitive sensing system at the bottom of the screen. Inanimate objects, fingernails, and gloves are invalid. Handwriting recognition is more difficult.
resistive touch screen vs capacitive touch screen
The precision of resistive touch screens and capacitive touch screens:
- Resistive touch screen: the accuracy is at least as high as a single display pixel, which can be seen with a stylus.Easy handwriting recognition and easy to operate in an interface that USES small control elements.
- Capacitive touch screen: the theoretical accuracy can reach several pixels, but it is actually limited by the contact area of fingers.It is difficult for users to accurately click on targets less than 1cm2.
Cost of resistive and capacitive touch screens:
- Resistive touch screens: They’re cheap.
- Capacitive touch screen: Capacitor screens from different manufacturers are 10% to 50% more expensive than resistive screens. This extra cost is fine for flagship products, but maybe prohibitive for mid-priced phones.
Multi-touch feasibility of resistive touch screen and capacitive touch screen:
- Resistive touch screen: impossible unless the resistive screen is reconnected to the machine’s circuit.
- Capacitive touch screen: depending on the implementation method and software, it has been implemented in G1 technology demonstration and iPhone.The 1.7T version of G1 already implements the browser’s multi-touch feature.