Four-quadrant detector signal amplification circuit

Abstract

The invention relates to a four-quadrant detector signal amplification circuit. The circuit comprises a four-quadrant detector and further comprises a trans-impedance amplifier, a voltage amplification circuit and an amplitude limiting amplification circuit which are sequentially connected with the four-quadrant detector, and the current output signals of the four quadrants of the four-quadrant detector after photoelectric conversion are transmitted to the trans-impedance amplifier, the voltage amplification circuit and the amplitude limiting amplification circuit respectively for signal amplification. According to the present invention, sirstly, by adopting the trans-impedance amplifier, and through the AC coupling, the direct-current noise of a photodiode is limited, a resistor at the positive end of an operational amplifier is used for compensating the leakage current of the photodiode, a capacitor connected with the operational amplifier in parallel is used for reducing the resistance thermal noise and improving the signal-to-noise ratio, and the amplification multiple of the signal is controlled through a feedback network of the voltage amplification circuit, and finally, through the amplitude limiting amplification circuit, the amplitude limiting amplification is realized by adopting the broadband high-gain voltage limiting amplifier, and the amplification multiple is determined through the feedback network, so that the effects of high gain and high bandwidth are realized.

Description

technical field [0001] The invention relates to the field of photodetector signal processing, in particular to a four-quadrant detector signal amplifying circuit. Background technique [0002] The four-quadrant detector is widely used in laser alignment, laser centering, laser guidance, laser guidance, laser warning, laser reconnaissance, laser automatic tracking and other fields due to its high spectral response range, high positioning accuracy, and fast calculation speed. middle. The four-quadrant detector is integrated with four photocells with almost identical performance in the form of four-quadrant distribution, and uses the magnitude of the light signals output by the four quadrants to calculate and locate the light spot according to a certain algorithm. Four-quadrant detectors are used in laser detection applications such as lidar. The laser echo signal is often weak, the laser repetition rate is high, and the laser pulse width is narrow. Lidar often requires a larg...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a four-quadrant detector signal amplification circuit, which is used to solve the problem that the existing four-quadrant photodetector cannot achieve high gain and high bandwidth for weak light signals

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