The capacitive screen can be simply regarded as a screen body composed of four layers of composite screens: from the outside to the inside, respectively, a glass protective layer, a conductive layer, a non-conductive glass screen, and a conductive layer. The innermost conductive layer plays a role in shielding the internal electrical signals. There are direct leads on the four corners or four sides of the middle conductive layer to detect the touch point position, which is a key part of the entire screen. Double glass protects the conductor layer and the sensor, which better supports multi-touch.
Advantages of industrial Panel PC using capacitive screen:
1. You can multi-touch.
2. High positioning accuracy.
Disadvantages of industrial Panel PC using capacitive screens:
1. The main disadvantage of capacitive screen is drift: when the ambient temperature, humidity, and electric field change, it will cause the capacitive screen to drift, which will cause the industrial tablet computer to operate incorrectly. For example, the temperature of the display panel rises after the industrial tablet computer is turned on, which will cause drift; when the user touches the screen, the other hand or the side of the body near the display will drift. The reason for the drift of the capacitive screen is technically inherent. Although the environmental potential surface is far away from the capacitive touch screen, it is much larger than the area of the finger, which directly affects the determination of the touch position.
2. The capacitive screen can only sense the touch of objects with bioelectricity, such as fingers. If you want to use other objects to operate the capacitive screen, the industrial tablet computer will not have any response.
A resistive touch screen is a sensor that converts the physical location of a touch point (X, Y) in a rectangular area into a voltage that represents the X and Y coordinates. The resistive touch screen is a thin film and glass structure. The adjacent surface of the thin film and glass is coated with an ITO (nano-indium tin metal oxide) coating. ITO has good conductivity and transparency. When touched, the ITO on the lower layer of the film will contact the ITO on the upper layer of the glass, and the corresponding electrical signal will be sent out through the sensor, which will be sent to the processor through the conversion circuit, which will be converted into the X and Y values on the screen by calculation, and the completion point The selected action is presented on the screen of the industrial tablet.
Advantages of industrial Panel PC using resistive screen:
1. The cost is cheap and the response sensitivity is very good.
2. It can adapt to a variety of harsh environments, and can operate industrial Panel PC with anything.
Disadvantages of industrial Panel PC using resistive screens:
1. It can only touch with one touch, that is, one place of the industrial Panel can be touched at a time. If you touch another place, it will have no effect.
2. As the resistive screen requires a certain amount of pressure, it will easily cause surface wear over time and affect the service life of the product.
3. The resistance screen has a poor ability to prevent misoperation. Anything touched will cause action.
How to distinguish between capacitive screen and resistive screen
The resistive screen does not support multi-touch. It can be controlled using sharp, insulated objects such as nails and stylus. The capacitive screen relies on the capacitance formed by the human body and the electrode to achieve positioning. It must be touched through the skin or other conductive objects can only be used, with a nail, stylus, etc. can not control the industrial Panel.