Single photon avalanche diode detector array used for laser range finding

Abstract

The invention discloses a single photon avalanche diode detector array used for laser range finding. The array comprises a single point detection surface, shaping circuits, an ''And'' processing circuit and an ''Or'' processing circuit. The single point detection surface is integrated by a plurality of detection single tubes in an n*n (n is greater than or equal to 2) mode. Each detection single tube includes a single photon avalanche diode and a quenching circuit. An output signal of each detection single tube is shaped to a pulse square wave signal by the respective shaping circuit. Each twopulse square wave signals form one group and are input into the ''And'' processing circuit. All the signals which are processed by the ''And'' processing circuit are processed by the ''Or'' processing circuit so as to generate a final output signal. By using the detector array, false triggering caused by dark counting and a stray light noise can be effectively reduced; detection efficiency is guaranteed and simultaneously range finding accuracy is ensured; and laser range finding with a high sensitivity can be realized.

Description

technical field [0001] The invention relates to the field of an integrated circuit designed based on a single-photon avalanche diode detector array, in particular to a detector suitable for the field of time-of-flight (TOF) laser ranging. Background technique [0002] In recent years, the field of unmanned driving or the field of assisted driving is in a period of vigorous development, and vehicle lidar technology is an important part of the research process. It is the large demand that promotes the great development of lidar, and a large number of domestic and foreign lidar technology and related companies have emerged. [0003] In the existing laser ranging technology, the detector mostly uses an ordinary avalanche photodiode (Avalanche PhotonDiode, APD). In order to ensure the consistency of the waveform under different light intensities, the back-end needs to do a series of complex circuit structures to process the signal. At the same time, its gain is limited, and the...

AI Technical Summary

Problems solved by technology

[0005] However, there are still some limitations and deficiencies in SPAD's real application in laser ranging technology.

The most difficult to rule out is the noise problem, the noise signal and the effective signal are indistinguishable on the waveform

There are two main sources of noise: 1. The dark count of the device itself due to the characteristics of semiconductor defects; 2. The stray light in the environment cannot be completely filtered out by the front-end color filter of the detector.

Therefore, these randomly generated noises may be regarded as valid signals, and mistriggered as STOP signals to the Time-to-Digital Converter (TDC, Time-to-Digital Converter), resulting in serious measurement errors

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