Touchscreen for the tablet. general information
The touchscreen for the tablet is one of the key components. It can be said, fundamental. If not for him, the work with the gadget would be done with the help of mechanical control buttons.
What it is
Touchscreen for a tablet or any other technique -this means of information input. This device is a screen that responds to touching it. It is he who is responsible for providing control signals to the operating system or applications on the gadget. If we draw an analogy, the touch screen is the mouse and the keyboard for the tablet.
- Resistive. The touchscreen of this type is a transparent membrane with a conductive coating applied, under which is a glass containing a similar layer. The principle of operation of this device is quite simple. When you press a stylus or a finger on the screen, the membrane and glass close at a certain point, resulting in a voltage change. The microprocessor captures these oscillations and calculates the coordinates. Such a touch screen is of low cost. Also in his favor says the possibility of feedback to touch any objects. But it has a low strength and a small working resource, which is about 35 million taps for each point. And - which is no less important - the lack of the possibility of implementing a multitouch. Also, the work of this display is accompanied by a large number of errors in the processing of gestures "sliding" and "turning over". This technology is not widely used in tablets. Today, you can meet single models of devices equipped with a similar touch screen. For example, the touchscreen for the tablet "TEXET TM-7020".
- Capacitive. This is the second technology by which touch screens are created. Work with such touch screens can only be done with your finger or with a conductive stylus. This kind of touchscreens can be divided into two categories: conventional and projection-capacitive. In the first type of devices, a conductive layer is applied to the glass. At the corners of the display are placed electrodes, which supply alternating voltage to the coating. When you touch the screen with your finger, a leakage occurs. The microprocessor monitors the point of contact. This is done by changing the electrode readings, since the nearest one significantly increases the current strength and decreases the resistance. A full multitouch on this type of screen will not work.
- A more advanced technology isprojection-capacitive. The internal side of the display in this case is covered with a grid of electrodes. When you touch one of them, a capacitor is formed, the capacitance of which is used to calculate the coordinates. This technology allows you to implement a full multitouch. That is, such a display is capable of supporting 2, 5 or even 10 simultaneous touches. A vivid example of the implementation of this technology is the touchscreen for the tablet "EXPLAY sQuad 9.71".
Ways of fastening
Installing the touch screen to the gadget is performedby gluing. The touchscreen for the tablet is mounted either on the display or on the case. In the first case, the glue base can be applied only along the perimeter or across the entire screen area. In the second case, it is distributed over the body parts with which the sensor contacts.
The touchscreen for the tablet can be made fromglass or plastic. In the first case, the touch screen has lower strength characteristics. In addition, when it is damaged immediately visible cracks. Devices made of plastic are more durable. And with damage, the appearance of cracks is unlikely.