TOF distance sensor, sensing array and distance measuring method based on TOF distance sensor

Abstract

The invention provides a TOF distance sensor and a distance measuring method based on the distance sensor, and the sensor comprises: an electronic device which is used for generating a modulation signal, i demodulation signal groups, and one reset signal; a radiation source used for emitting radiation; a receiving device for receiving radiation reflected by an object; a determination correction means used for correlating the received radiation with a corresponding one of the demodulation signals to form a plurality of correlation values, obtaining the time between a rising edge of the demodulation signal corresponding to the maximum correlation value in the plurality of correlation values and an emission starting point of the modulation signal, taking the time as the time delay of the emission starting point of the demodulation signal, and reducing a current pulse width of the demodulation signal; a circulating device used for circularly carrying out time delay on the emission startingpoint of the demodulation signal through the determination correction means until the current pulse width of the demodulation signal is a set threshold value; a correlation device used for acquiringa plurality of correlation values which are finally used for calculation; and a calculation device that calculates a distance from the object.

Description

technical field [0001] The invention belongs to the technical field of laser radar, and in particular relates to a TOF distance sensor, a sensing array and a distance measuring method based on the TOF distance sensor. Background technique [0002] With the development of laser technology, embedded technology and integrated optics, laser ranging is developing in the direction of digitization, automation, low cost and miniaturization. Laser ranging radar has the advantages of high precision, small system size and rapid measurement, and has a wide application prospect. [0003] Traditional laser radar detectors mostly use single-point or multi-line scanning measurement methods, which require a mechanical scanning device, slow scanning speed, and low image spatial resolution. TOF (time-of-flight) technology is generally used for distance measurement. This technology can be applied in industries such as automobiles, artificial intelligence, games, and machine vision. Laser trans...

AI Technical Summary

Problems solved by technology

Therefore, in practical applications, in order to avoid the high quantum efficiency of the photosensitive area of ​​the pixel in the visible light band for the TOF sensor using the CMOS process, the laser wavelength is usually set in the near-infrared band (850nm ~ 1100nm) with weak atmospheric spectral energy. , coupled with restrictions on the use of long-distance ranging, low-power laser ranging, and focal plane imaging ranging, further weakened the laser echo energy entering a single pixel

Although increasing the photosensitive surface and integrating time will improve the quantum collection efficiency of the laser echo, the parasitic effect of the large photosensitive area affects the bandwidth, and the inability to separate the DC background light signal from the storage readout node introduced by the long integration period will seriously affect the The ranging accuracy and measurement range of TOF are difficult to balance between "high-precision ranging and not far away" and "long-distance ranging with large errors". At the same time, the TOF ranging method without modulation and demodulation mechanism has caused laser measurement Mutual interference between devices

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