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Table 3
Lens features.
| Inner radius | 0.25 m |
| Outer radius | 2.26 m |
| Focal length | 20 m |
| Number of rings | 100 |
| Geometric area | 158 496 cm2 |
| Crystal radial length | 20 mm |
| Crystal tangential length | 10 mm |
| Crystal thickness | 5 mm |
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