Instructions for machine vision calibration board for camera calibration

1. Confirm the performance of the optical system and restore the one-to-one correspondence between the 3D space of the camera model and the 2D space.

One of the functions of calibration is to find the distortion coefficient (because there will be more or less distortion after imaging through the lens), and the other is to get the correspondence between the spatial coordinate system and the image coordinate system. . 2. The positioning accuracy is as high as 0.001mm; 3. The classic checkerboard calibration board, solid circle array calibration board, and halcon calibration board are compatible with the calibration algorithms of most image processing algorithms.

The following takes the halcon calibration board as an example:

The halcon calibration board is compatible with the German MVtech company's Halcon and ActiveVision Tools machine vision software development kits.

With a border and a bevel on the periphery, a 7x7 dot matrix

Take the 60*60mm specification as an example:

7*7 array

Outer border length: 60mm *60mm

Inner border length: 58.125mm*58.125mm?

That is: the black border line is a dot with a radius of 1.875 (the diameter is 3.75)

Black Dot diameter: 3.75mm

Dot center spacing: 7.50mm

Corners: indent from the black outer border by the length of the center margin (7.50mm)

This is the calibration board specification generated by the halcon calibration description file