====== Value of Two Prisms Stacked in the Same Direction (Prism Diopters) ======
|                |  **1st Prism**                                          |||||
| **2nd Prism**  | **10Δ**         | **20Δ**  | **30Δ**  | **40Δ**  | **50Δ**  |
| **10Δ**        | 21              | 33       | 46       | 60       | 77       |
| **20Δ**        | 33              | 47       | 66       | 89       | 122      |
| **30Δ**        | 46              | 66       | 94       | 141      | 264      |
| **40Δ**        | 60              | 89       | 141      | 339      |          |
| **50Δ**        | 77              | 122      | 256      |          |          |

{{tag>strabismus}}