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Comparison table for the phantom test with different types of spacers.
| Spacer | Setting Angle (°) | Average Measurement Angle (°) | Error (°) |
|---|---|---|---|
| Type A (d = 2.5 mm) |
45° | 46.3° | 1.3° |
| 90° | 91.2° | 1.2° | |
| 135° | 136.5° | 1.5° | |
| Type B (d = 5.0 mm) |
45° | 47.7° | 2.7° |
| 90° | 93.1° | 3.1° | |
| 135° | 137.5° | 2.5° | |
| Type C (d = 10.0 mm) |
45° | 49.8° | 4.8° |
| 90° | 95.9° | 5.9° | |
| 135° | 139.9° | 4.9° |
d means thickness of the spacer.
