What Are The Components of A Capacitive Touch Screen Module?

Capacitive touch screen modules are mainly composed of the following parts:

Outer Cover:

This is the part that users touch directly, usually made of glass or plastic.

The surface is treated with special methods, such as scratch resistance and fingerprint prevention, to enhance the reliability of touch and improve the user experience.

Conductive Layer:

Located beneath the overlay, it is made of transparent conductive materials such as ITO (Indium Tin Oxide) or metal mesh.

The function of the conductive layer is to form a capacitance with the human body when touched, thereby detecting the position of the touch.

The conductive layer is divided into two directions: horizontal (X-axis) and vertical (Y-axis).

Insulating Layer/Isolation Layer:

Located between the conductive layer and the sensor, it is used to isolate the two conductive layers and prevent capacitive coupling between them.

Typically made of insulating materials such as polyester film or glass fiber.

Touch Detection Screen:

Responsible for detecting the location and type of touch events.

In a capacitive touch screen, the touch detection screen determines the position of the touch by measuring the change in capacitance between the conductive layers when touched.

Backlight LED:

For TFT-LCD capacitive touch screen modules, backlight LED lights are used to provide the background light source for the screen.

Display Liquid Crystal:

Responsible for displaying images and text.

Drive Backplane (PCB Drive Backplane):

For powering the display and converting driver signals (RGB interface signal, touch I2C interface signal).

Different touch screen modules may require different power supply voltages and signal interfaces.

Interfaces:

Touch screen modules typically have two main interfaces: RGB display driver interface and capacitive touch screen interface.

The RGB display driver interface is used to connect the display and the driving backplane, providing display signals.

The capacitive touch screen interface is used to connect the touch detection screen and the driving backplane, transmitting touch signals.

Other auxiliary components:

It may also include components such as OCA (Optically Clear Adhesive) for bonding and protecting connections between layers.

The above are the main components of a capacitive touch screen module, and there may be some differences in specific implementations between different manufacturers and models.