Hi Hao,

Thank you for your post!

Regarding your first question, when entering Start Order as -57 OS will automatically set the Stop order to -18, because there can only be 40 orders being traced simultaneously at one time. You can find this discussed in the help file at The Setup Tab > Editors Group (Setup Tab) > Non-sequential Component Editor > Object Properties (non-sequential component editor) > Diffraction (object properties, non-sequential component editor)

This means you can only trace 40 orders simultaneously. Some of the parameters under the Object Properties can be varied using Multiconfig operand NPRO, but it seems this Start and Stop order setting are not supported by NPRO so you can only trace 40 orders in one system. 

Regarding your second question on designing DOE using OpticStudio, our engineer Michael wrote a KBA on this topic at How to design DOE lens or metalens in OpticStudio. Binary 1 is certainly one option to go for DOE design. As for all the parameters associated with Binary 1, you can find those explained in the help file at The Setup Tab > Editors Group (Setup Tab) > Non-sequential Component Editor > Non-sequential Geometry Objects > Binary 1 (non-sequential geometry objects)

Best,

~Hui