What is touch display

Simply put, a touch screen display is an integrated device that combines a display screen and a touch screen: it not only outputs images like a regular display, but also allows users to directly click, slide, and write on the screen with their fingers or stylus to complete input, hence it is also called a touch display or touch screen display. It is not the same as a separate "touch screen" - the touch screen is only responsible for detecting the touch position and belongs to the input component; A monitor only displays images and is an output component; The touch screen display combines the two into a complete "display+interaction" terminal, which can be used as a "manually operated display" by plugging in the signal cable.

Upon disassembly, a touchscreen display consists of five parts: an LCD, LED, or OLED display panel responsible for imaging; The touch detection layers such as resistors, capacitors, infrared, surface acoustic waves, and optics are responsible for sensing the contact points; The touch controller converts the position of the touch points into coordinate signals; The driver and interface board handle both video and touch signals; The shell and installation structure determine whether it is desktop, wall mounted, embedded, or industrial panel form. When wiring, touch screen displays usually go through two channels: video signals come in from HDMI, DisplayPort, VGA, DVI, or USB-C, and touch coordinates are transmitted back to the host through USB, serial port, or HID interface. After obtaining the coordinates, the system maps them to the corresponding position on the screen, so clicking the button on the screen is equivalent to clicking the mouse. It is worth noting that the two channels are independent of each other - just because the touch screen display is on does not mean that the touch is connected. Conversely, when the USB cable is not properly plugged in, the screen is normal but does not respond when clicked, which is the most common "false fault" in on-site troubleshooting.

According to the technical route, there are significant differences in personality among various types of touch screen displays. Capacitive touch screen displays rely on changes in human body current for positioning, support multi touch and gesture operations, have high transparency and smooth hand feel, and are frequent visitors to mobile phones, tablets, and conference screens. Industrial models can also recognize thick gloves and wet hands after firmware tuning; Resistive touch screen displays rely on two layers of pressure contact positioning, which is cost friendly, not afraid of oil stains and static interference, and can be operated with nails or touch pens. They are widely used in industrial consoles, POS cashiers, and ATMs, but their shortcomings are low light transmittance and lack of support for multi-point operation; Infrared and optical touch screen displays are equipped with transmitting and receiving tubes on the frame, and rely on shading to determine the contact points, making it easy to achieve a size of 55 inches or even larger. They are commonly used in advertising machines, electronic whiteboards, and conference tablets, and are scratch resistant, wear-resistant, and have a long lifespan. However, the frame is thick and afraid of direct sunlight interference; Surface acoustic wave touch screen displays have outstanding clarity and transparent touch, but once the glass surface is stained with water droplets, oil stains, or dust, it will be misjudged, gradually replacing the first three in public environments.

In terms of application, the landing point of touch screen displays almost covers all positions of "human-machine dialogue": in self-service terminals, POS cash registers, ordering machines, and government inquiry machines, it is the main interface for customers to operate manually; On CNC machine tools, instruments, and production line workstations, industrial grade touch screen displays should be equipped with fanless sealed bodies and IP65 front panels, resistant to dust and scrubbing, and able to touch with gloves as usual; Conference tablets and interactive teaching use large-sized multi touch screen displays, with board annotations and wireless projection completed on one screen; There are touch screen displays of corresponding sizes next to medical equipment, in car central control, and in 86 boxes of smart home panels; Public information dissemination, advertising machines, and access control intercoms often use touch screen displays that support vertical installation and remote control.