Figure 1.
The measurement system
Figure 2.
Schematic diagram of camera imaging
Figure 3.
Principle of camera imaging
Figure 4.
Camera distortion
Figure 5.
Rasterization of the checkerboard calibration board
Figure 6.
Design drawing of calibration board
Figure 7.
The calibration process based on circular marking points
Figure 8.
Main view of calibration board
Figure 9.
Position relationship diagram between points and straight lines
Figure 10.
Automatic matching of marking points at different angles
TABLE I.
THE BACK PROJECTION ERROR RESULTS OF THE ALGORITHM
| Group | ea | em |
|---|---|---|
| 1 | 0.191 | 0.650 |
| 2 | 0.177 | 0.801 |
| 3 | 0.266 | 0.502 |
TABLE II.
BACK-PROJECTION ERROR RESULTS OF ZHANG'S CALIBRATION METHOD
| Group | ea | e m |
|---|---|---|
| 1 | 0.613 | 1.124 |
| 2 | 0.691 | 2.316 |
| 3 | 0.827 | 1.528 |
TABLE III.
MEASUREMENT INFORMATION OF DENTAL MODEL (UNIT: MM)
| Name | Average measurement result of this system | Measurement standard deviation | LJ-V7000measurement results |
|---|---|---|---|
| Arch length | 63.87 | 0.10 | 63.91 |
| Arch width | 58.02 | 0.12 | 58.03 |
| 41 teeth | 5.58 | 0.12 | 5.63 |
| 42 teeth | 6.52 | 0.09 | 6.45 |
| 43 teeth | 7.28 | 0.11 | 7.32 |
| 44 teeth | 7.89 | 0.17 | 7.89 |
| 45 teeth | 7.48 | 0.06 | 7.46 |
| 46 teeth | 11.00 | 0.07 | 10.97 |
| 31 teeth | 5.41 | 0.08 | 5.41 |
| 32 teeth | 6.39 | 0.10 | 6.31 |
| 33 teeth | 6.98 | 0.07 | 7.06 |
| 34 teeth | 7.79 | 0.12 | 7.76 |
| 35 teeth | 7.45 | 0.07 | 7.43 |
| 36 teeth | 11.05 | 0.13 | 10.95 |