At present, there are many types of so-called touch screens. Generally, the touch screen is composed of different components from the liquid crystal display of the display device. A transparent touch screen is attached to the front of the display device. This kind of touch screen is called a "narrow" touch screen. Generally, the input medium is a finger.
In addition, there are input devices using special pens or touch screens with touch-control functions in the recent liquid crystal display itself. These are called "broad" touch screens.
Narrowly defined touch screens are roughly divided into four types: resistive, capacitive, optical, and ultrasonic. Broad sense touch screens include electromagnetic induction type and In Cell type. These methods are classified in Figure 2-1. Because no touch screen is omnipotent, there are multiple touch screens. For example, the resistive type is the only superior method that does not choose to enter the media, but it has poor durability and is not suitable for the operation needs of the public. Although capacitive or optical touch screens are relatively expensive and have limitations in use, they are more suitable for products such as electronic kiosks that require long-term durability.
classifies touch screens from different perspectives, which can be divided into "electronic detection methods" and "non-electrical methods". The touch screen using electronic detection is mainly resistive and capacitive. In this case, it is necessary to use a transparent conductive film such as ITO (Indium Tin Oxide) or ATO (Antimony Tin Oxide), which may reduce the transmittance. But its disadvantage is that even if this optical method is superior in optical characteristics, it will often have the shortcoming of wrong operation.
