Raster imaging system and its scanning method

Abstract

The invention discloses a grating imaging system, wherein the system includes: a source grating (G0), which is used to convert incoherent light emitted by a light source into coherent light; a first grating (G1) formed by splicing a plurality of first grating units , used to obtain the first imaging after the coherent light passes through the first grating (G1); and a second grating (G2) formed by splicing a plurality of second grating units, used to operate the first imaging to obtain the second imaging; wherein , the imaging irradiation position is set between the first grating (G1) and the second grating (G2), and the source grating (G0), the first grating (G1) and the second grating (G2) form an optical path to form a system. While maintaining good image quality, the overall scanning time is reduced to a level close to that of clinical X-ray chest films, and the radiation dose is well controlled; in general, the large-field raster imaging system has a large imaging field of view. , fast scanning speed, low radiation dose and other advantages and characteristics.

Description

technical field [0001] The invention relates to the technical field of optical imaging, in particular to a grating imaging system and a scanning method thereof. Background technique [0002] X-ray grating phase-contrast imaging technology can realize local structure resolution on micron or submicron level, which is a good supplement to traditional X-ray imaging technology. This technology can simultaneously extract three kinds of information of absorption, phase contrast and dark field images, and is suitable for the distinction between low atomic number and low density substances, especially for biological soft tissue structures including breast. In order to obtain better image quality, grating imaging technology usually acquires data by phase stepping. This method refers to displacing one of the gratings along the direction perpendicular to the grid line of the grating in one or more cycles, so as to obtain the displacement curve before and after placing the object. [0...

AI Technical Summary

Problems solved by technology

A larger imaging field of view also means a larger grating group, and the current grating manufacturing process cannot be processed in one go

Similarly, for the traditional grating imaging method, the measured object is generally scanned by moving relative to the grating, and the scanning process is more complicated; in addition, the traditional phase step scanning is time-consuming, and the radiation dose is high, which is harmful to the measured object.

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