Common issues with calibration boards:
1. What is a calibration board?
Calibration Target is used in applications such as machine vision, image measurement, photogrammetry, and 3D reconstruction to correct lens distortion; Determine the conversion relationship between physical dimensions and pixels; To determine the three-dimensional geometric position of a point on the surface of a spatial object and its corresponding point in the image, it is necessary to establish a geometric model for camera imaging.
By shooting a flat panel with a fixed spacing pattern array using a camera and performing calibration algorithms, the geometric model of the camera can be obtained, resulting in high-precision measurement and reconstruction results. The flat panel with a fixed spacing pattern array is the calibration board.
2. What are the materials of the calibration board?
There are usually two types of materials for calibration boards:
(1) Soda glass
The calibration plate of glass substrate is widely used in transmissive visual measurement systems, with characteristics such as low coefficient of thermal expansion, high accuracy, high hardness, and good corrosion resistance.
(2) Ceramic material
The ceramic calibration plate adopts a ceramic substrate standard plate, which has the characteristics of low thermal expansion coefficient, high strength, high hardness, good wear resistance, low thermal conductivity, and good acid and alkali resistance. Its good surface diffuse reflection treatment solves the problem of reflection of glass material calibration plate under the condition of front light source in the application process, and can better identify the detailed information of the calibration plate pattern, thereby achieving higher calibration accuracy and measurement accuracy.
3. What are the types of calibration boards?
Common types of calibration boards include: international chessboard calibration board, solid circular array calibration board, grid calibration board, ceramic calibration board, and so on. Other calibration boards can be customized according to requirements.
4. What are the common calibration board specifications?
——The common specifications of the dot calibration board are as follows:
External dimensions (mm) Dot diameter (mm) External dimensions (mm) Dot diameter (mm)
Glass calibration board
63ⅹ63 3.5 63ⅹ63 2
63ⅹ63 3 63ⅹ63 4
100ⅹ100 2 100ⅹ100 3
100ⅹ100 4 100ⅹ100 5
125ⅹ125 3 125ⅹ125 5
138ⅹ138 6 275ⅹ225 3（4个Φ7）
300ⅹ300 3
600mm×800mm
Other special specifications can be customized according to customer requirements
Ceramic calibration plate:
50ⅹ50 63ⅹ63
100ⅹ100 200ⅹ200
300ⅹ300
——The common specifications of the chessboard calibration board are as follows:
External dimensions (mm), grid dimensions (mm), external dimensions (mm), grid dimensions (mm)
Glass calibration board:
63ⅹ63 1ⅹ1 63ⅹ63 2ⅹ2
63ⅹ63 3ⅹ3 63ⅹ63 4ⅹ4
63ⅹ63 5ⅹ5
100ⅹ100 4ⅹ4 100ⅹ100 5ⅹ5
100ⅹ100 6ⅹ6 125ⅹ125 3ⅹ3
125ⅹ125 5ⅹ5 200ⅹ200 3ⅹ3
200ⅹ200 5ⅹ5 206ⅹ206 3ⅹ3
300ⅹ300 3ⅹ3 300ⅹ300 5ⅹ5
300ⅹ300 20ⅹ20 351ⅹ351 1.35ⅹ1.35
600mm×800mm
Other special specifications can be customized according to customer requirements
Ceramic calibration plate:
63ⅹ63 100ⅹ100
125ⅹ125 200ⅹ200
300ⅹ300
