Guilin Sun
Ansys Employee

Binary quality is lost? do you mean it chages the geometry such as hole sizes? you can modify the threshold for image import to change the refractive index. An alternative method is to create the binary object with script: https://optics.ansys.com/hc/en-us/articles/360034382754-Binary-spatial-data-Simulation-object

If the problem still exists, please give some screenshots and explain the procedures you followed.