Both four-wire and five-wire resistive touch screens belong to the category of resistive screens. They are controlled by pressure sensing to make contact between the layers of the screen. There are many ways to touch, including fingers and touch pens. Below, we conduct a simple comparative analysis of four-wire and five-wire resistive touch screens through various aspects.

1. Brief introduction of four-wire resistive touch screen

The advantage of the four-wire resistive touch screen is that it can not only calculate the horizontal X and Y coordinates, but also measure the vertical Z coordinate, that is, the pressure of the finger. This is obtained by measuring the longitudinal contact resistance Rtouch. The value of this resistance can be measured It is used to quantify the contact pressure and convert it into the required instructions.

The disadvantage of the four-wire resistive touch screen is durability, and the long-term touch and pressure will damage the device. Because every time you touch it, the PET and ITO on the upper layer will deform, and the ITO material is brittle and easy to damage when deformation occurs frequently. Once the ITO layer is broken, the uniformity of conductivity is also destroyed, resulting in inaccurate proportional equivalence when deriving coordinates. This kind of breakage is very likely to occur in areas that are frequently touched, such as the confirmation key. Another disadvantage is that the ITO attached to the PET active substrate will not be fully oxidized. Once exposed to a humid or heated environment, the oxidation will lead to an increase in resistance, which will also destroy the uniformity of conductivity and cause errors in coordinate calculations, that is, "drift" Phenomenon.

Two, the origin of the five-wire resistive touch screen

The various shortcomings of the above four-wire resistive touch screen gave birth to the concept of a five-wire resistive touch screen. The structure adopted by the five-wire resistive touch screen is to attach the X and Y electrodes to the ITO layer of the glass substrate, and the ITO on the upper layer is only used as an active electrode. The X and Y electrodes of the bottom ITO lead out UL, UR, LL, LR from the four corners, and the active electrodes on the upper layer, so there are five lines in total. The advantage of the five-wire resistive touch screen is that the glass substrate is relatively firm and not easy to deform, and it can fully oxidize the ITO attached to it. The glass material will not absorb water, and its expansion coefficient is very close to that of ITO, and the deformation will not cause damage to ITO. The ITO on the upper layer is only used as the lead-out electrode, and no current flows, so uniform conductivity is not required, and even if it is damaged due to deformation, it will not cause the resistive screen to "drift".

Five-wire resistive touch screen
Analysis of the differences between three, four-wire and five-wire resistive touch screens

Four. Summary

The four-wire resistive touch screen has a relatively simple process and low cost, and can meet the needs of small-sized consumer products. From the perspective of cost control and economy, it is a good solution. The five-wire resistive touch screen has better light transmittance, click life, sensitivity, durability, etc., and can meet product solutions with larger sizes and higher requirements. But at the same time, due to the more complicated process, the cost will increase accordingly. Customers need to choose a suitable resistive touch screen according to their own needs.

Contact:Mr. Bin

E-mail:
binyq@ahtongchi.com

Phone:
+86-0566-5229929

Address:
Building 1, Fu'an Industrial Park, Chizhou Development Zone, Guichi District, Chizhou City, Anhui Province