Index grating is a common method to alter the frequency characteristics of light. In Rsoft, a graded index component is found under the “Index Taper” tab when right-clicking on a component. By selecting the tab “Tapers…”, one can create a new index taper.
Here, the taper is called “User 1” and defined by an equation step(M*z), with z being the z-coordinate location.
Selecting “Test” on the User Taper Editor will plot the index function of the tapered component:
The index contour is plotted below:
Here, the field pattern:
Light contour plot: