A Touch Screen Controller Board is a circuit that acts as an interface between a touchscreen device’s sensors and its operating system. It translates commands into signals that the sensor can understand, such as changes in electrical current from a finger touch.
When choosing a controller, consider its features and how it will work with your display. For example, it should support a high-resolution screen and be compatible with your video source.
Capacitive
Touchscreens are the backbone of Human-Machine Interface (HMI) panels. These devices enable intuitive and efficient control and monitoring of industrial machinery and production processes. They are also used to provide better clarity and precision for users. While resistive touchscreens respond to external factors such as temperature, humidity and light, capacitive touchscreens are less affected by these variables and offer higher levels of clarity and accuracy.
Capacitive touchscreens have a separate touch sensor and cover lens to protect them from mechanical stresses and optical deformation. The adhesive used to bond the cover lens and touch sensor must be able to withstand tensile, compressive and shear forces.
The touch sensor is powered by the LCD controller board via a short low impedance ground path. This ground connection must be insulated from any metal that may be present in the device chassis to avoid electrical noise and potential galvanic corrosion. In addition, the circuit and chassis grounds must be at the same voltage to prevent signal interference.
Resistive
Resistive touchscreens overlay a flat panel display and allow you to interact with displayed symbols by touching specific areas. They detect the precise location of the touch and transmit this information to the application software. The application software then determines what further screen actions should occur.
The touch sensors in a resistive touchscreen monitor consist of several thin layers that bend when pressed. The layer that bends closes a circuit and generates a current. This is detected by the sensors in the corners of the screen.
The sensor outputs a voltage gradient in the X and Y directions. This voltage can be read with the help of a special circuit. The circuit uses two ICs that function as dividers. One of the ICs outputs the Y direction results and the other outputs the X direction results. The Y and X results are combined to determine the coordinates of the touched point on the screen. Four and five wire resistive touchscreens require different bias configurations to read the X and Y coordinates of the touch points.
Infrared
Infrared-based touch screens detect touch input based on interruptions in infrared light beams projected over the screen. They are suitable for a variety of applications, including self-service kiosks and retail displays. They are also ideal for industrial use due to their robust construction and ability to withstand contaminants, such as dust and grease.
IR touchscreens use LEDs embedded in the screen frame to emit invisible infrared beams in a grid across the surface of the overlay. Photodetectors installed around the frame detect these beams and register their X and Y coordinates. The digitized signal is then compared to a list of corresponding positions to identify the touched location.
Unlike PCAP touchscreens, which require an electrode film to register a touch, IR screens can be activated with any object that is not transparent, including bare fingers, thin surgical gloves, or wet hands. They are also less susceptible to wear and tear, making them a cost-effective solution for large displays.
CP-TOUCH
Whether it’s a simple tap or a multi-touch gesture, a touchscreen controller turns these inputs into seamless on-screen actions that enhance the user experience. It’s a crucial part of any human machine interface (HMI) or self-service terminal, converting the signals from a touch screen into commands that the device’s operating system can understand. For more details please visit Touch Screen Controller Board
This is accomplished by a series of circuits that sense when a finger or other object touches the display panel and sends the corresponding signal to the touchscreen controller. The controller processes the touch information to identify the corresponding command and relay it to the OS for execution.
Typically, the controller also includes circuitry that can detect when the finger is wet or dirty, as well as other advanced features like gloved hand support, palm rejection, custom gestures and force sensing. It’s important to keep your touch controller software current in order to avoid any security issues. It also helps improve performance and reduces the amount of processing power required.