The capacitive type senses touch by changing the capacitance between the human body and the electrode, and the resistive type changes the resistance by pressing. The internal infrared touch PCBA amplifies and filters the signal, and converts the signal into a digital signal to identify the touch.

Active infrared emission, according to the object occlusion or reflection of the infrared part of the receiver (receiver tube on the PCB) signal changes; The infrared ray of the object is detected passively and processed by PCB to generate output signal.

Focusing on touch signal processing, there are high-precision analog circuits, conversion chips and filter circuits, and there may be MCU to realize gesture recognition and other functions, and there is a communication interface design.

The focus is on infrared signal processing. The active type has the transmit and receive circuit, the passive type pays attention to the signal strength and the time difference analysis, some has the temperature compensation circuit.

Touch sensor Application scenarios:

It is mainly used in consumer electronics (such as mobile phones, tablet touch screens) and smart home (such as lamp touch switches).

Infrared sensor application scenarios:

Widely used in security (such as automatic induction door) and thermal imaging equipment.