When to use grids in X-rays

The appearance of the grid plate is a flat plate with a thickness of 4~8mm. The internal structure is made up of many thin lead strips intersecting and arranging. The two lead strips are filled and positioned with an X-ray-transparent material and glued together. The filler can be wood, paper or aluminum, and saffron etc. Finally, the top and bottom are encapsulated with thin aluminum plates to form a grid plate. From the cross-section, the arrangement direction of the lead strips of the filter plate will converge to one point. From the whole grid, there is a convergence line. Its main function is to filter out the influence of scattered rays on the film. It should be placed between the human body and the film, and most of the scattered rays can be filtered out, and only a small part of the scattered rays of the sea are leaked. So, when you feel that the image quality is average, you can use the grid.
According to the structure, the wire grid can be divided into four types: convergence grid, parallel grid, cross grid and arc grid:
1 Convergence grid: each lead strip is inclined to the focus, that is, the lead strip extension line is concentrated in the focus
2 Parallel grid: each lead bar is parallel to each other in the vertical plane
3 Cross gate: It is composed of two layers of parallel gates, and the directions of the lead bars are 90° to each other.
4 Circular arc grid: It is formed by superimposing the center to expand with equal radii, tile-shaped
To choose the right grid, three important parameters need to be identified:
1 Focal length: the vertical distance from the convergence line of the lead strip to the surface of the grid, f
2 Grid ratio: also a grid ratio, which is the ratio of the height of the lead bar to the gap of the lead bar, R
3 Grid density: the number of lead bars in the unit distance range and file range, please feel free N

Author：X Ray Grids Maker