ToF pixel structure capable of simultaneously capturing depth and gray information

Abstract

The invention discloses a TOF (Time Of Flight) pixel structure capable of simultaneously capturing depth and gray information. The TOF pixel structure consists of a PMOS (P-channel Metal Oxide Semiconductor) tube P1-P2, a photodiode Photo-detector, a differential comparator DDA, a transparent latch, a high-speed ADC (Analog to Digital Converter), an NAND gate NAND and an AND gate AND, a photosensitive part in the pixel structure adopts a three-FD structure, two FDs are used for collecting depth information signals, and the two FDs are connected with a pixel internal integrated double-end differential comparator. The double-end differential comparator can effectively filter visible light information and convert depth information into pulse number, and signal reading is carried out through acounter outside a pixel. And the other FD is used for sensing visible light information and reading the visible light information through an analog-to-digital converter outside the pixel. According to the invention, depth information and gray scale information can be captured at the same time, real-time fusion processing is carried out, the detection performance of the ToF-based 3D image sensor is improved, and the use occasion is broadened.

Description

technical field [0001] The invention belongs to the field of image sensors, in particular to a three-dimensional image sensor (TOF) pixel structure that simultaneously captures depth and grayscale information. Background technique [0002] As an extension of human senses, sensors realize accurate and reliable acquisition and conversion of external information. CMOS image sensors play an important role in various fields. In recent years, the demand for 3D image sensors has increased, figure 1 A schematic diagram showing the effect of two-dimensional imaging and three-dimensional imaging. 3D image sensors can be used in 3D reconstruction, automatic processing, height measurement, etc. in the industrial field; in the military field, they can be used for drone detection, submarine navigation, interstellar telemetry imaging, etc.; in the automotive field, they can be used for unmanned driving and assisted driving; In consumer electronics, it is used in somatosensory games, ges...

AI Technical Summary

Problems solved by technology

At the same time, the position of the field of view of the target object image captured by different sensors is also different, which also increases the difficulty of later image fusion

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