Sometimes traditional means of dialogue with a computer, such as a mouse and trackball, are not entirely convenient. Then the optimal solution is the touch panel. For a small monitor, this is most relevant. The name itself comes from the ability to respond to touch. The monitor reflects an image representing the program menu in an accessible and understandable form. The user works with the system using ordinary touches to a specific picture. Thus, a special program receives the coordinate of the contact point, comparing it with a particular image.
The modern touch panel with high accuracy determines the element of the program menu selected by the user. These days, there are types of screens that can recognize contact from almost any subject. The interaction of a person with a computer by pointing a finger at a specific element is considered the most natural action. This property is taken into account primarily by developers of various devices and systems around the globe. However, touch panels have many other advantages that other means of dialogue with a computer cannot boast of. The presence of any buttons can give real flexibility to the interface. There is a possibility of quick adaptation to unusual conditions.
Any touch panel includes a multilayer screen, usually having a flat shape. On the inside, a supporting glass is installed, providing rigidity to the entire structure. At the edges of the screen there are contacts that allow you to read electrical signals. Using the controller, the source signal is converted to one that is suitable for processing. As for the interface, it is a controller node, including a connecting cable, connector and the necessary drivers. Its task is to transmit information from the controller to the base control node.
Depending on the method of receiving the signal and finding the touch point, the touch panel may be of a certain type. The most widespread are resistive structures with a multilayer structure. Their device provides for the presence of two conductive surfaces, separated by an insulating composition. When touching the outer layer, the surface is connected to the conductive layer of the main plate.
Another type is a capacitive touch panel, which uses glass as a sensitive element. On the glass surface is a thin conductive coating. When you touch the screen, a capacitive connection is formed between the finger and the surface. The distance to the touch point is determined by the proportionality of the electric current from each corner of the screen. The controller, comparing these currents, sets the contact point. There are also analogues on surface acoustic and infrared waves. However, their manufacturability and high cost currently do not allow them to become widespread.