How it works

The IR receiver head internally includes IR monitoring diode, amplifier, limiter, bandpass filter, integrator circuit, comparator, etc. The IR monitoring diode detects the IR signal and sends the signal to the amplifier and limiter, which controls the pulse amplitude to a certain level regardless of the distance between the IR transmitter and receiver. The AC signal goes to the band-pass filter (the band-pass filter can pass a load wave of 30khz to 60khz), and then through the demodulation circuit and the integrator circuit to the comparator, which outputs a high and low level to restore the signal waveform at the transmitter.