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With an emphasis on improving the fidelity even in super-resolution regimes, new imaging techniques have been intensively developed over the last several years, which may provide substantial improvements to the interferometric observation (such as ALMA) of protoplanetary disks (PPDs). In this talk, I will introduce a novel super-resolution imaging technique utilizing sparse modeling to enhance the fidelity and spatial resolution of the ALMA images, as well as its principle. Next, I will turn to our recent results of high-resolution images of 43 Taurus-Auriga protoplanetary disks with spatial resolutions ranging from 0.01 to 0.1 arcseconds (1-14 au at a distance of 140 pc), 2-3 times higher than those obtained from conventional imaging technique. The resolved dust disks have radii that widely range from 8 to 238 au but exhibit a roughly similar average surface brightness temperature of 8 K. The analysis revealed various substructures, such as gap and ring, regardless of disk size. The locations of the gaps show bimodal distribution peaking at 10-20 au and 30-100 au. The locations of gaps and rings show a linear relationship, while several systems do not lie in this correlation. Such outlier’s gap widths are 2-3 times larger than typical sizes on the corresponding locations. Finally, I will discuss two types of these disks with different gap sizes that indicate the presence of two distinct planet-forming mechanisms by assuming that the gaps are carved by planets and that their sizes are proportional to planetary masses.