two touch methods of touch all-in-one
September 6, 2021
With the rapid advancement of technology in recent years, the touch all-in-one machine has evolved from a simple query business to an intelligent product integrating multiple functions. The application field has gradually spread to various industries. The touch all-in-one machine is in restaurants or conference halls. , Or in large-scale scenic spots, you can see the touch all-in-one. At present, there are two types of touch all-in-ones in the industry. Today we will elaborate on these two touch methods for you:
The first type: capacitive sensing touch
The capacitive touch all-in-one machine uses the current induction of the human body to work. The capacitive touch screen is a four-layer composite glass. The inner surface and the interlayer of the glass screen will be coated with a layer of ITO, and there is a layer of silica glass on the outside. The protective layer of the sandwich ITO layer is used as the working surface. Four electrodes will be drawn on the four corners. The inner ITO layer is the shielding layer, mainly to ensure the working environment. When the finger touches the metal layer, due to the human body The self-existing power forms a coupling capacitor between the user and the touch screen. For high-frequency currents, the capacitor is a direct conductor, so the finger draws a small current from the contact point. This current flows from the four corners of the shielding layer. The electric power flowing through the four electrodes is proportional to the distance from the finger to the four corners. The controller obtains the specific position of the touch point through the accurate calculation of the four current ratios. Therefore, capacitive touch The surface of the all-in-one is very flat.
The second type: infrared touch
The display screen used by the infrared touch all-in-one machine is an infrared touch screen, which uses an infrared matrix densely distributed in the X and Y directions to detect and locate the user’s touch. The infrared touch screen is actually installed with a circuit board frame in front of the display. The circuit board will arrange infrared emitting and receiving tubes around the screen, corresponding to the horizontal and vertical cross infrared matrix. When the user touches the display screen, the finger will block the two horizontal and vertical infrared electronic whiteboard lines corresponding to this position. Therefore, the position of the touch point on the screen can be judged. The infrared touch screen is a highly integrated electronic circuit integration product. At the same time, the infrared touch also includes a complete integrated control circuit, a set of high-precision, anti-interference infrared emitting tubes and a set of The infrared receiver tube is installed in two opposite directions on a highly integrated circuit board to form an invisible infrared grating. The intelligent control system embedded in the control circuit continuously pulses the diode to form an infrared polarized beam grid. In order to realize the infrared touch function, the infrared touch screen is generally suitable for a slightly larger touch all-in-one machine, such as 49 inches, 55 inches or 65 inches.