Hello!
Attached image shows the prism ring parameter calculated by the Rx software. Can someone kindly teach me the calculation method?
Click image for larger version. 

Name:	1_different fornt curve_1.PNG 
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ID:	9458Click image for larger version. 

Name:	2_different fornt curve_2.PNG 
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ID:	9459Click image for larger version. 

Name:	3_different Index.PNG 
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ID:	9460Click image for larger version. 

Name:	4_different Bolck ring diameter.PNG 
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ID:	9461.