Multiple access tomographic coding Bessel beam microscopy

Abstract Optical imaging has always been an efficient and intuitive imaging method in microscopy. To overcome the limitations of diffraction, a point-by-point scanning strategy is usually used for high-resolution imaging of large scenes. However, this approach results in lengthy imaging times, and the large amount of mechanical motion required for scanning tends to reduce the robustness of the system. Moreover, in microscopic imaging, weak optical signals with extremely low signal-to-noise ratios are often difficult to detect. To tackle these drawbacks, we propose a method using spatiotemporally encoded Bessel beams in microscopy. Due to the good orthogonality and autocorrelation of each encoded beam, we can efficiently separate the individual light signals at the receiving end. The non-diffracting and self-healing properties of Bessel beams enable imaging at large depths. We elaborate on the principles of beam encoding and decoding, then a home-made microscopy system is used in the experiment. By imaging polystyrene microspheres with an average diameter of 2 microns, we have experimentally demonstrated that our method is capable of obtaining clear imaging results, and imaging speed has been increased due to the reduction of a large number of scans. After decoding, the signal-to-noise ratio of the signal is enhanced, and its value shows a logarithmic relationship with the number of coded bits, which is consistent with our theoretical estimates.