According to a newly published paper, Harbin Institute of Technology has made important progress in the development of a new bio-optical microscopy imaging technique that is expected to introduce a new technique in 3D imaging.
Associate Professor Wang Jian from the School of Physics at Harbin Institute of Technology recently published a paper in the latest issue of the optics journal Optica titled "Airy-beam Tomographic Microscopy" to present the latest research results.
His team proposed a new scanning-free, high-resolution, three-dimensional microscopy technique ATM, based on the Avery light field, and successfully applied to Biological Cell Imaging.
Optica is the flagship journal of Optics of America (OSA) and Associate Professor Wang Jian is the first author of the paper.
The Gaussian-distributed optical field is frequency-domain modulated to produce an Avery beam with diffraction-free, self-healing, and self-accelerating properties.
The diffraction-free property of the beam helps to improve the resolution of optical imaging; the self-healing property reduces the scattering effect of the beam through the medium. Improved imaging signal-to-noise ratio; self-accelerating feature enables the lateral self-bending propagation of light beams in free space.
Combining the above features, the team proposed a unique three-dimensional microscopic imaging method based on the reconstruction of two-dimensional projection images ATM ( See Figure 1), it is possible to reconstruct high-resolution 3D target images without mechanical scanning simply by changing the pattern on the modulator.
Figure 1 ATM imaging principle
The ATM imaging process includes a number of innovative technologies such as Avery Beam Propagation Control, PSF control, and projection reconstruction algorithms through the Chirp processing in the frequency domain increases the propagation distance in unilateral direction of the focal plane, suppressing the effect of the paraflap of the beam on the imaging resolution.
Particle imaging experiments show that the technique has a lateral resolution of 400-700 nm under a 40x objective and a depth resolution of 1-7.5 nm. 2 μm.
This technique was used in the article to observe the renal tubules and glomeruli in mouse kidney cells (see Figure 2), compared to conventional z-scan imaging The ATM technology provides high signal-to-noise ratio and enables deep field of view (10 microns or more) imaging without mechanical scanning.
Combined with the Avery Beam 3D reconstruction imaging algorithm, ATM lateral resolution is close to the optical diffraction limit and super resolution is achieved in the depth direction.
This technique is expected to be applied in other 3D imaging techniques.
Fig. 2 (a) Conventional z-scan imaging of renal tubules; (b) ATM imaging of renal tubules; (c) and (d) ATM imaging of renal tubules. Three-dimensional structural and cross-sectional maps; (e) two-color z-scan imaging of the glomerulus (upper 568 nm; lower 488 nm); (f) Two-color ATM imaging of the glomerulus (upper 568 nm; lower 488 nm); (g) two-color synthetic image; (h) figure (g) ) in an enlarged view of the tubular structure; (i), (j), (k) half-height width diagrams of the three dimensions of the tubular structure.
