Analysis of mainstream technology behind the popul

Behind the popularity of touch panel: mainstream technology analysis

in recent years, the application of touch panel can be said to be more and more widely. From the early military or some special applications, to the current many places have adopted touch panel, if Yahoo! Or if Google searches with the touchpanel keyword, it grows with hundreds of results every day and presses into the surface of the tested material under a constant load. It can be seen that the touch panel has become a popular and rapidly growing application and market. However, touch panel has more than 4 or 5 technologies and many manufacturers have invested in it. If some customers want to use touch panel, they are bound to be dazzled and overwhelmed by a variety of information. This article is based on the current mainstream and future technologies, and hopes to provide some useful references for readers who are first involved in touch panel

resistive

resistive touch screen can be said to be one of the most used technologies at present. The driving principle of resistive touch screen is to find the coordinate axis by means of voltage drop. As can be seen from the figure below, x-axis and y-axis are driven by a pair of 0 ~ 5V voltages respectively. When the resistive touch screen is touched, the circuit will be turned on, resulting in voltage drop, The controller will calculate the proportion of the voltage drop, and then further calculate the coordinate axis

from the perspective of resistive structure, usually the upper layer of resistive structure is made of itocoating pet, and the lower layer is made of itocoating pet or glass. When it is not normally used, the upper and lower layers are supported by insulator spacerdot, otherwise there will be a problem of Jiangsu Jinfa science and technology new Material Co., Ltd. invested by Jinfa science and technology group with constanttouch (cursor fixing every point)

general resistive structured filmonglass (FG), that is, the upper layer is itocoating pet, and the lower layer is itocoating general glass. The disadvantage is that if the general glass is accidentally broken in use, glass fragments will cut the user

in order to avoid such accidents, 3M specially adopts a safer architecture, polyesterlaminated (PL). The upper layer is itocoating pet (refer to the figure below), but the lower layer is itocoating pet, optical glue, and chemically strengthened glass (from top to bottom). The pressure resistance of chemically strengthened glass is 3.4 times stronger than that of ordinary glass. When the chemically strengthened glass is unfortunately broken, the optical glue can cover the fragments of the chemically strengthened glass in a whole layer to prevent the fragments from cutting the user, just like the heat insulation paper of the automobile windshield, it will only crack but not break. The safety of the resistive panel with this kind of polyesterlaminated structure is far better than filmonglass (FG)

capacitive

capacitive touch panel, compared with resistive, is a completely different technology. The capacitive structure is relatively simple. Basically, it takes ITO glass as the main body, discharges at the four corners of ITO glass, and forms a uniform electric field on the surface. When conductive objects, such as human fingers, absorb a small amount of current, The later controller will calculate the proportion of current being sucked away and calculate the x-axis and y-axis

light transmittance

the touch panel is attached to the outside of the LCD, so its light transmittance and its anti glare and anti reflection characteristics are also relatively important. It is not easy for capacitive touch panel to achieve high light transmittance and anti glare. Generally, the light transmittance is only 85%. And the anti dazzle effect is also poor

however, 3M's new generation capacitive capacitive touch screen, cleartek II, has a light transmittance of 91.5%, and its surface is treated with anti glare and anti reflection. Compared with the resistive touch screen, the capacitive touch screen brightens the whole vision, and the whole visual texture is also improved a lot. The manufacturers of touch screens do not have to go to the user to set and transform the LCD at will to improve the brightness, which saves a lot of costs

hardness

the surface of the resistance type is made of pet (plastic), and the hardness is usually 3H. The so-called h hardness here is the hardness of our pencils, such as 2B and Hb pencils. We all know that pencils are easy to break when using pencils, and they will become brittle after adding the aging of plastic. The resistance touch panel is easy to damage 51 acid resistant bricks. It's ok if the resistance type is used in PDA or other personal items, Usually, we will take great care of our own things, but if it is public, it is easy to be damaged due to careless use or improper use, which will usually cause trouble in the maintenance of manufacturers, not to mention the opportunity cost lost by customers because the machine cannot be used

3m adopts 3M's exclusive hardcoat on the surface of the capacitive panel, which can make the surface of the capacitive panel reach the hardness of glass. Mohs' grade ranges from one to ten, and the hardest grade is ten: diamond. Capacitive panel is very suitable for various occasions, because the hardness of 7mohs can easily be competent for various applications and the destruction of users