In this paper,the liquid-based scattering microspheres phantom is studied, in order to evaluate the resolution of optical coherence tomography (OCT) equipment. By mixing pure water and polystyrene (PS) microspheres in proportion to fabricate solutions of different concentrations. The disadvantages of polydimethylsiloxane (PDMS) substrates are overcame, such as complex production process, microbubbles, uneven distribution or clustering of microspheres, easy tearing, and relatively low imaging contrast. The encapsulated liquid-based scattering microspheres phantom is characterized by optical microscopy, which shows that the microspheres are uniformly distributed without clustering. It can effectively improve the accuracy of resolution evaluation of OCT equipment. At the same time, the automatic identification, averaging and fitting of microspheres in OCT test images are realized by programming, and the evaluation results of lateral and axial resolutions are given automatically. Finally, the liquid-based evaluation phantom is validated by testing the resolutions of a commercial OCT equipment.
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