Discussion Forum

If I understand you correctly, you are asking about how to use the 2D and 3D drawing tools. I encourage you to work through some of the tutorials available in the Applications Library. Also, just experiment with the features provided. The Help system is sometimes actually helpful, too. Operations such as extrude, sweep, revolve, and loft are definitely worthy of some study, in addition to the various Boolean operations, and such simple operations as move, rotate, scale, and others. Learn how to use Workplanes. Learn about using bezier curves and parametric curves, surfaces, etc. After enough practice and experience, you will be quite skilled in creating very complex and completely custom geometries. See also https://www.comsol.com/support/learning-center .

Thank you for your reply. I have no problem to draw. I am referring to the tutorial Tapered Waveguide. The tutorial shows down tapered, but my design structure is combining a down tapared(left), straight waveguide (middle) and upper tapered (right). I am doubt that i can use the same step for DEFINITION and STUDY.

2) I also confuse what is the different with d_taper and n_taper as mentioned in parameter file ?

n_taper 200 "Taper length in vacuum wavelengths" d_taper n_taper*lam0 "Taper length"

3) Why use lam0 as 1.55um wavelength? can use UV wavelength?

Thank you in advanced

Sorry, I thought you were talking about an RF waveguide model. The model to which you refer is optical. But, more importantly, it also involves some rather careful customizations, so I suggest that other readers -- those more familiar than I am with novel optical fiber structure modeling using Comsol Multiphysics -- respond.

Anyway, thank you for your concern. I really apprecieated it. Hope for an optical simulator can help me for some solutions ;-)