Resistive Touch screen has been popular around in 2003, when single touch mobiles were popular. the main application for mobile phone and Car DVD . The touch screen factories in China were rapidly growing.at that on the market mainly producing 4 wire and 5 wire resistive touch screens. Even now in 2019 for some industry Resistive touch screen are still the first choice because of cost-effective, durable, waterproof, dustproof, versatile solution features. When you ask for price from the Manufacturer,we know that for the same size touch screen, 5 wire resistive touch screen will be more expensive than 4 wire. So What’s the main technical difference between 4 wire and 5 wire touch screen ?
4 wire touch screen is a 2 layer structure that’ s consisted of a ITO conductive film in upper layer and ITO conductive glass or film in bottom layer which are separated by extremely small, transparent spacer dots. The 2 layers are coated with a resistive substance called ITO, when the ITO film is pressed down, and the 2 layers are contacted, That results the electrical contact, producing the voltages. It presents the position touched.
One of these layers contains electrodes in
the Y direction, whereas the other layer contains electrodes in the X direction
The two layers are designed to measure the voltage created by the opposite
layer.
To get the “X”
touch position, the controller sets Pin4 to +5V and Pin2 to GND (0V). Pin1 is
left unconnected. The controller uses Pin3 to read the voltage where the top
layer meets the bottom layer. The controller converts the voltage to a number
(data) and sends it to the host computer.
To get the “Y” touch position the
controller sets Pin1 to +5V and Pin3 to GND (0V) Pin2 is left unconnected. The
controller uses Pin4 to read the voltage where the top layer meets the bottom
layer. Again, the controller converts the voltage to a number (data) and sends
it to the host computer.
Notice that some pins switch functions
depending on if the controller is looking for a X-touch or a Y-touch position
The controller reads the X and Y position many times per second so the user may
move his stylus (or finger) rapidly across the touch screen and the data will
be captured. This provides smooth operation and allows drag-and-drop or
signature capture
the 5 wire resistive touch screen also consists of a conductive glass bottom layer and conductive top film layer. The fundamental difference between the two is, in the 5- wire resistive touch screen construction, all the electrodes are on the bottom layer and the top layer acts as a voltage-measuring probe. With this structure, the touch screen may still work properly even when the top layer is slightly scratched or damaged. The result is an accurate, durable and reliable touch screen that offers a higher touch life.