Traversal Window Inversion of 3-D Boundary of Micro Magnetic Target Based on Quantum Imaging Technique

• Published in: IEEE transactions on instrumentation and measurement 2024, Vol.73, p.1-10
• Main Authors: Hao, Wenyuan, Fei Wen, Huan, Gao, Ziheng, Liu, Yanjie, Wang, Ding, Li, Xin, Li, Zhonghao, Guo, Hao, Ma, Zongmin, Tang, Jun, Liu, Jun
• Format: Article
• Language: English
• Subjects: 3-D boundary inversion; Accuracy; Image color analysis; Magnetic fields; Magnetic resonance imaging; nitrogen-vacancy (NV) color centers; regularized inversion; Superconducting magnets; Three-dimensional displays; traversal matrices; vector magnetic field detection; Vectors; wide-field of view
• ISSN: 0018-9456; 1557-9662
• DOI: 10.1109/TIM.2024.3428594

The 3-D boundary identification of magnetic targets is of significant importance for the magnetic characteristics assessment of magnetic devices. A high-fidelity reconstruction method for the 3-D boundary of tiny-sized magnetic targets through inversion techniques is presented in this article. Based on nitrogen-vacancy (NV) color centers in diamond, vector magnetic imaging with high sensitivity, wide field of view, and alignment-free is realized. Based on the anomaly distribution of the total magnetic field intensity (TMI), we determined the spatial dimensions and depth for the inversion and discretized the 3-D space into a grid. In order to overcome magnetic field noise and overlapping interference, we proposed a multiwindow inversion model by constructing inversion windows of various sizes. The application of various window sizes for inversion, along with the utilization of their corresponding gradient weights in a weighted combination, effectively addresses the ill-conditioned inversion challenges stemming from the nonlinear crosstalk of magnetic field noise. The experimental results show that the proposed method can achieve an inversion accuracy of 99.1% with a sensitivity of 2~\mu T/ \surd Hz. Compared with the method of L0-L2 norm regularization inversion, the inversion accuracy is improved by 3.5%. This method opens up a way for high-fidelity 3-D magnetic target boundary inversion.