The proliferation of touchscreen options is fueled by the advancement of technology. Therefore, choosing one will entirely depend on how much convenience it will bring to using the device.
Resistive touchscreens are preferred by many industries, though, for their applications. It has several advantages, including affordability and the ability to operate with multiple touches (gloves, bare fingers, and a stylus).
A resistive touchscreen's internal components include two layers of glass and film coated with a transparent conductive material, both of which are separated from one another by an air gap and microdots. The voltage at the point of contact is read through conductors at the edges of each layer in the case of a 4-wire or just the bottom layer in the case of a 5-wire when the flexible top or front layer is compressed. The touch point's location is determined by the voltage that was read there.
According to design, the two most prevalent types of resistive touchscreens that we have are the 4-wire and 5-wire versions. The subtle differences between the 4 and 5-wire resistive touchscreens can help you understand them if you are thinking about getting a resistive-wire touchscreen but are unsure about the design.
Each of the two layers in 4-wire resistive touchscreens has conductive bus bars printed along two of their opposing edges. Bus bars will be placed on the top and bottom of one layer and the left and right edges of the other layer, respectively. With the positive connected to one bar and the negative connected to the other, the controller will apply a DC voltage across one of the layers. Depending on how close it is to the positive buss bar or the negative buss bar, this will cause a voltage flow through the conductive coating of that layer that varies in voltage level. The controller uses the opposing layer as a voltage probe to measure the voltage at the touch point when a touch event takes place, bringing the opposite layer into contact with the voltage layer. The controller can then pinpoint the location of the touch point in that single plane (X or Y). The controller flips the layer functions to cause the same thing to occur in X rather than Y, or vice versa, to obtain the other plane. The layer functions are typically flipped more than 100 times per second, so there is no reporting lag for the X and Y coordinate readings.
The advantage of 4-wire resistive touchscreens is the affordable solution they provide. It continues to be the most affordable touch panel for entry-level applications.
Only the lower layer of the voltage is measured by 5-wire touchscreens. A 5-wire touchscreen differs from a 4-wire resistive touchscreen in that it only uses the top layer as a voltage probe to measure the voltage of the bottom layer. 4-wire resistive touchscreens use both layers to measure voltage. The 5-wire operates similarly to the 4-wire in that it measures the voltage in one plane and then flips the application of voltage to the other plane. However, it only operates on the bottom layer, which has a unique conductor pattern around its perimeter that enables this function to be performed on a single layer. It indicates that the micro-damage to the upper no-load voltage probe layer will not impair the performance or accuracy of the touchscreen.
Five-wired touch panels are favored for commercial applications over four-wire resistive touchscreens because they are more durable, accurate, and long-lasting. A 5-wire resistive touchscreen, though slightly more expensive, is an investment that can pay off in the long term.