A resistive touch screen is a sensor whose principle is to convert the physical position of the touch point (X, Y) in the matrix area into a voltage representing the X coordinate. The resistive touch screen is a structure of film and glass. The adjacent sides of the film and glass are coated with ITO (nano-indium tin metal oxide) coating. ITO has good conductivity and transparency. When a touch operation is performed, the ITO on the lower layer of the film will contact the ITO on the upper layer of the glass, and a corresponding electrical signal is transmitted through the sensor, sent to the processor through the conversion circuit, and converted into X and Y values on the screen through calculation, and the point is completed. The selected action is displayed on the screen of the industrial tablet computer.
Advantages of using resistive screens for industrial tablet computers:
1. The cost is cheap and the response sensitivity is also very good.
2. It can be used in various harsh environments, and the industrial tablet computer can be operated with anything.
Disadvantages of using resistive screens for industrial tablet computers:
1. It can only be single-touch, that is, you can only touch one place on the industrial tablet computer at a time. If you touch another place, it will have no effect.
2. Since 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 resistive screen has poor ability to prevent malfunctions, and anything that touches it will cause it to move.
Capacitive touch screen technology works by using the human body’s current induction. The capacitive screen can be simply regarded as a screen composed of four layers of composite screens: from the outside to the inside, they are a glass protective layer, a conductive layer, a non-conductive glass screen, and a conductive layer. The innermost conductive layer serves to shield internal electrical signals. The middle conductive layer has direct leads on the four corners or sides to support the detection of the touch point position, which is a key part of the entire screen. Double glass can protect the conductor layer and sensor to better support multi-touch. The inner surface and interlayer of the glass screen are each coated with a layer of ITO. The outermost layer is a thin layer of silica glass protective layer. The interlayer ITO serves as the working surface. Four electrodes are drawn from the four corners. The inner layer of ITO is a shielding layer to ensure good working environment.
Advantages of using capacitive screens for industrial tablet computers:
1. Multi-touch is possible;
2. High positioning accuracy.
Disadvantages of using capacitive screens for industrial tablet computers:
1. The main disadvantage of the capacitive screen is drift: that is, when the ambient temperature, humidity, and electric field change, it will cause the capacitive screen to drift, resulting in inaccurate operation of the industrial tablet computer. For example, after the industrial tablet computer is turned on, the temperature of the display screen will increase, which will cause drift; when the user touches the screen, the other hand or side of the body is close to the display, which will cause drift. The drift of the capacitive screen is caused by inherent technical shortcomings. Although the environmental potential surface is far away from the capacitive touch screen, it is much larger than the finger area, which directly affects the determination of the touch position.
2. The capacitive screen can only sense the touch of bioelectric objects, such as fingers. If you want to use other objects to operate the capacitive screen, the industrial tablet computer will not respond in any way.
The above is an introduction to the differences and advantages and disadvantages of resistive screens and capacitive screens. I hope it will be helpful to readers.
Post time: Oct-26-2023