In terms of the durability index of the touch screen, its performance indexes are different according to different purposes. The durability indexes include: number of hits, vibration, impact, etc., in addition to the tensile strength and flexural strength of the FPC connected to the external circuit . In dictated game products, the touch screen is also continuously tapped with a pen, so the structural design of the touch screen is very important. Generally, resistive film/glass structures can be knocked up to 1 million times. The emergence of the five-wire structure of the touch screen has extended the number of screen taps.
The general resistive touch screen is a four-wire type. In actual operation, if the upper substrate film or conductive film is deformed, problems will occur. The electrodes of the four-wire resistive touch screen are respectively located on the X axis and the y axis of the upper and lower substrates, but the electrodes of the five-wire resistive touch screen are all arranged on the X axis and the F axis of the lower substrate. In a five-wire resistive touch screen, the top electrode only functions to sense the access point and is hardly damaged. Compared with a four-wire resistive touch screen, its impact life is much longer. In addition, the upper substrate of the four-wire resistive touch screen uses a thin glass structure, the transparent electrode has good contact with the glass substrate, and its knock life is longer. The touch screen has also developed a material that is not a transparent electrode of ITO, which is a metal nanostructure. The high-molecular-weight polymer substrate made of this transparent electrode material has excellent flexibility and can significantly increase the impact life.
Environmental reliability indicators mainly include high temperature storage, low temperature storage, high temperature and high humidity rotation, cycle temperature storage, and high temperature action test and low temperature action test while power is on. In addition, according to customer requirements, performance indicators such as chemical resistance, dust resistance, and salt spray condensation can also be added. Reliability tests are all based on the operating temperature and storage temperature described above. That is, the upper and lower limits of the temperature for the placement test are within the storage temperature range, and the upper and lower limits for the operation test are within the operating temperature range. Table 4-7 lists the performance parameters of standard mode, medium reliability and high reliability.
