Touch technology was initially developed for the military, medical and other technology industries. The working environment in these application fields is relatively harsh because there are water and gloves that may affect touching as well as electromagnetic interference, which are problems that have to be solved. The resistive touch technology can solve these problems well. However, when capacitive touch screen technology was first developed, it was intended for commercial markets of tablets and smartphones with multi-touch finger touches, which were not suitable for harsh environments with water or gloves. Therefore, resistive touch technology and capacitive technology have had their applicable fields.
Touch technology has come a long way and resistive touch technology is no longer the best choice since its only advantage is its low price. Although the hot days of resistive touch technology are over, there are still many people who mistakenly associate resistive touch with better performance in industrial applications and devalue the capacitive technology in the consumer market. The resistive touch panel used to almost monopolize the industrial display field due to its electromagnetic compatibility, which is a key feature in the industrial application market. Nowadays, projected capacitive touch screen technology is developing rapidly. It can not only work in environments with water, thick gloves, or severe electromagnetic interference, but also support multi-touch technology. It can easily cope with various touch display fields such as medical display, industrial application, and outdoor handheld. It has advantages of durability, small size, light friction and excellent touch texture, it also has benefits in commercial display fields such as smartphones and tablet computers.
The biggest advantage of the capacitive touch screen is its high touch precision, fast response and multi-touch support. The capacitive touch screen achieves multi-touch mainly by increasing the electrodes of mutual capacitance. To be specific, the screen is divided into blocks, and a set of mutual capacitance modules is in each block to work independently. Therefore, the capacitive touch screen can independently detect the touch situation of each area and achieve multi-touch after processing. When the user touches the capacitive screen, the user's finger and the working surface form a coupling capacitance due to the electric field of the human body. The finger will absorb a small current because the working surface is connected to a high-frequency signal. This current flows out from the electrodes at each corner of the screen, and the current flowing through each electrode is theoretically proportional to the distance between the fingers and corners. The position of the controller can be obtained by precise calculation of the ratio of the four currents. Therefore, the capacitive touch screen can achieve 99% accuracy and has a response speed of less than 3ms.
Do you have an answer in your mind from this article? Each terminal product and each customer has its considerations. We need to analyze multiple dimensions such as product cost, touch effect, product demand, and working environment in detail and then get an optimal touch panel display solution.