High-resolution depth imaging with a small-scale SPAD array based on the temporal-spatial filter and intensity image guidance

Currently single-photon avalanche diode (SPAD) arrays suffer from a small-scale pixel count, which makes it difficult to achieve high-resolution 3D imaging directly through themselves. We established a CCD camera-assisted SPAD array depth imaging system. Based on illumination laser lattice generated by a diffractive optical element (DOE), the registration of the low-resolution depth image gathered by SPAD and the high-resolution intensity image gathered by CCD is realized. The intensity information is used to guide the reconstruction of a resolution-enhanced depth image through a proposed method consisting of total generalized variation (TGV) regularization and temporal-spatial (T-S) filtering algorithm. Experimental results show that an increasement of 4 x 4 times for native depth image resolution is achieved and the depth imaging quality is also improved by applying the proposed method. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

Currently, single-photon avalanche diode (SPAD) arrays face the challenge of having a small pixel count, making it difficult to achieve high-resolution 3D imaging directly. In this study, we propose a CCD camera-assisted SPAD array depth imaging system that utilizes a diffractive optical element (DOE) to generate an illumination laser lattice. This system aligns the low-resolution depth image captured by SPAD with the high-resolution intensity image captured by CCD. To enhance the resolution of the depth image, we introduce a method combining total generalized variation (TGV) regularization and temporal-spatial (T-S) filtering algorithm, guided by the intensity information. Experimental results demonstrate a 4x4 increase in the native depth image resolution and an improved depth imaging quality.