Calibration Target is used in machine vision, image measurement, photogrammetry, three-dimensional reconstruction and other applications to correct lens distortion; determine the conversion relationship between physical size and pixels; and determine the three-dimensional geometric position of a point on the surface of a space object and its location. The relationship between the corresponding points in the image requires the establishment of a geometric model of the camera imaging.

Through the camera's shooting of the fixed-spacing pattern array plate and the calculation of the calibration algorithm, the geometric model of the camera can be obtained, so as to obtain high-precision measurement and reconstruction results. The flat plate with a fixed-pitch pattern array is the calibration plate.

Optry optical glass series calibration plate and ceramic series calibration plate are commonly used calibration tools for university experiments, research unit project development and machine vision integrators product calibration, machine vision, image measurement, photogrammetry and other customer groups. Obtain the calibration data of the camera.

The function of the calibration board:

In order to correct lens distortion, determine the conversion relationship between physical size and pixels, and determine the relationship between the three-dimensional geometric position of a point on the surface of an object in space and its corresponding point in the image, it is necessary to establish a geometric model of camera imaging. It is a special high-precision calibration tool for research units and the field of vision, 3D image measurement, 3D reverse engineering, stereo matching, 3D reconstruction, etc. It mainly obtains the data of camera calibration results through calibration software.

Optry Optics can customize various calibration plates and calibration sheets.

Standard manufacturing process: The glass substrate is polished, cleaned, coated, etc. The film layer is firm, and there are few defects in the post-production process. If one of the processes is reduced or the machine used is not very good, the cost of the product will be much cheaper, and the quality must not be very good.

About the selection of calibration board:

1. Select the calibration plate size:

Select the appropriate calibration plate according to the size of the field of view. It is recommended in the halcon document that the size of the calibration plate pattern should be at least larger than 1/4 of the field of view and smaller than the entire field of view, and take 15-20 calibration images; it is recommended that the pattern of the calibration plate be larger than 1/3 of the field of view , less than the entire field of view, the number of calibration images depends on the requirements; for the calibration board of the halcon12 version, it is recommended that the pattern of the calibration board be larger than the field of view area, and about 5 calibration images with different attitudes; the calibration board of the halcon12 version currently only supports halcon12, but halcon12 Version software can use calibration boards from previous versions.

2. How to choose the calibration plate material:

Please choose a ceramic/metal calibration plate for the front light source to avoid reflection. The backlight source can choose optical glass material.