The working principle of Infrared Receiver Module and its wavelength identification mechanism
Publish Time: 2024-05-11
The working principle of Infrared Receiver Module is based on the phenomenon of infrared radiation. Specifically, its work includes the following main steps:Receive infrared light signal:The core component in the Infrared Receiver Module is an infrared sensor, usually a photodiode (PD). When an infrared transmitter (such as a remote control) emits infrared light signals, these signals travel through the air as light. The infrared sensor in the Infrared Receiver Module can sense and receive these infrared light signals.Convert optical signals into electrical signals:After the infrared sensor receives the infrared light signal, it converts it into a weak electrical signal. This electrical signal is very weak and requires further processing before it can be identified.Amplification and filtering:The converted electrical signal is first amplified by an amplifier to a level that can be processed. Next, the filter is used to remove noise and unnecessary frequency components to improve the signal-to-noise ratio of the signal.Demodulation and shaping:The amplified and filtered signal is sent to the demodulator, which restores the modulated infrared signal to the original encoded signal. The demodulated signal may also need to go through a waveform shaping circuit to ensure that its shape and timing meet the requirements for subsequent processing.Decoding and output:Finally, the demodulated and shaped signal will be decoded by the decoding circuit to restore the original instructions or data sent by the remote control or other transmitting equipment. The decoded signal will be output to the external circuit through the output pin for subsequent use by the device or system.How to distinguish and receive infrared light signals of specific wavelengths:Optical filter: The Infrared Receiver Module usually contains one or more optical filters, which are used to selectively allow infrared light of specific wavelengths to pass through. In this way, only infrared light signals that meet the requirements can enter the receiving module, and unnecessary signals will be filtered out.Spectral response: The infrared sensor itself also has a specific spectral response range, that is, it can only respond to infrared light within a certain wavelength range. Therefore, by choosing the appropriate combination of infrared sensors and filters, you can ensure that the receiving module only receives infrared light signals of specific wavelengths.Signal identification: Inside the receiving module, through processing steps such as demodulation, shaping and decoding, the infrared signals emitted by different devices or different buttons can be further distinguished and identified. The infrared signal emitted by each device or key has unique encoding and waveform characteristics, so different signals can be distinguished by these characteristics.
