How to divide the density of the grid

The grid should be placed between the human body and the film, which can filter most of the scattered rays, and only a small part of the scattered rays will leak.
The structure of the grid and the specifications of the grid: The grid has the following three main technical parameters:
The focal length of the grid: the vertical distance from the convergence line of the lead strip to the surface of the grid, f
The grid ratio of the grid: It is also a grid ratio, which is the ratio of the height of the lead bar to the lead bar gap, R
The grid density of the grid: the number of lead bars within a unit distance, N
The grid is classified according to the structure:
1 Convergence grid: each lead bar is inclined to the focus, that is, the extension line of the lead bar is concentrated on the focus
2Parallel grid: each lead bar is parallel to each other in the vertical plane
3Cross grid: It is composed of two layers of parallel grids, and the lead strips are 90° to each other.
4Circular arc grid: It is formed by overlapping from the center outwards with equal radius, tile-shaped

Author：Lillian