Nowadays, touch display devices have been an indispensable part of people's life and work, it changes our life to make it more convenient and efficient. There are several types of touch screens as follows:
Resistive touch screen uses pressure sensing for control. The screen is relatively thin, any object touch can be displayed, but easily scratched.
Infrared touch screen using infrared pass detection and positioning. Users choose a good light transmittance baffle, and anti-reflective treatment, you can get a good visual effect. However, by the infrared tube volume limitations, it is not possible to emit high-density infrared, so the resolution of this touch screen is not high.
Surface acoustic wave touch screen is a kind of ultrasonic waves, in the medium (such as glass or metal and other rigid materials) surface shallow propagation of mechanical energy waves. The technology is stable, and the controller of the surface acoustic wave touch screen relies on the measurement of the decay moment on the time axis to calculate the touch position, so its accuracy is very high. However, it works in a demanding environment, the dust in the air covers the reflective stripes around the touch screen or transducer when it will affect the correct positioning of the system.
Capacitive touch screen works by using the current induction of human body. High resolution, light transmittance, etc. can meet the requirements of all aspects, but the insulation of the medium can not sense the work. Capacitive touch screen is more commonly used nowadays, so what are its advantages and disadvantages?
Advantages of capacitive touch screen:
1. operation novelty. Capacitive touch screen support multi-touch, the operation is more intuitive, more interesting.
2. Not easy to accidentally touch. Because capacitive touch screen needs to sense the current of the human body to work. Only the human body or a specific capacitive pen to operate it, with other objects will not react when touched, so basically avoid the possibility of accidental contact.
3. High durability. Compared with resistive touch screen, capacitive touch screen has better performance in dustproof, waterproof, wear-resistant and so on.
Capacitive touch screen, despite the rich interface, multi-touch, only to the human body sensing and other advantages, but at the same time, it also has the following defects:
1. susceptible to environmental influences. Temperature and humidity and other environmental factors such as the onset of changes will also cause instability and even drift capacitive contact screen. For example, the user in the use of the body close to the screen may cause drift, or in the congestion of the crowd operation may also cause drift. This is mainly due to the operating principle of capacitive touch screen caused by the user's finger interval screen closer, but there are many volume near the screen is much larger than the finger of the electric field together with the effect, which will affect the judgement of the contact position.
2. High cost. In addition, the capacitive touch screen in the touch panel attached to the LCD panel in the process there are still certain technical difficulties, the yield rate is not high, so invariably also increase the cost of capacitive touch screen.