Structure Group

This section describes structure groups.

Structure group is a collection of structures and serves as a tool for managing and editing objects within the group, which facilitates users to model and design optical devices.

Features:

• Not only enable unified operations on structure units within a structure group, but also allow users to change properties of individual objects within a group.
• The setup script allows users to customize any structure group to facilitate overall optimizations and sweeps.

Utilizing structure groups for modeling makes the design of optical devices easy and efficient.

Built-in Structure Group Library

For common structures, the software offers a variety of structure groups to facilitate users in accomplishing complicated modeling tasks.

Built-in Structure Group Library

Name	Description
Cylinders	Including Custom revolution, Gear cylinder, Rough cylinder, Rough wire, and Rounded cylinder.
Cylindrical fibers	Including Bragg fiber, Core-cladding fiber, and Vertical multilayers.
Ellipsoids	Including Coated ellipse, Coated sphere, Dimer sphere, and Hemisphere.
Extruded polygons	Including All rounded quadrilateral, Complex n-sided polygon, Cross, Equation mirrored line, General polygon, Isosceles trapezoid, N-sided equilateral polygon with rounded corners, N-sided equilateral polygon, Parallelogram, Rectangular polygon with rounded corners, Star polygon, Equilateral triangle, Isosceles triangle, and Right-angle triangle.
Gratings	Including Blaze grating, Bragg grating, and Grating coupler.
Integrated optics	Including 180-deg waveguide bend, 90-deg waveguide bend, Cross waveguide, Directional coupler, Ring resonator, S-bend waveguide, Straight waveguide, Y-combiner, and Y-splitter.
Photonic crystals	Including BCC PC lattice, Circular lattice PC array, FCC PC lattice, FCC(111) PC array, Hexagonal lattice PC H-cavity, Hexagonal lattice PC L-cavity, Hexagonal lattice PC array, Hexagonal lattice PC intersection, Hexagonal lattice PC waveguide, Rectangular PC lattice, Rectangular lattice PC array, Rectangular lattice PC waveguide, Woodpile, and Rectangular lattice PC intersection.
Polyhedrons	Including Disdyakis dodecahedron, Regular octahedron, and Truncated octahedron.
Pyramids and cones	Including Coated pyramid, Cone, Diamond, N-sided Pyramid, N-sided Truncated pyramid, Parabola cone, Rounded tip cone, Tetrahedron, Truncated cone, and Truncated ellipse cone.
Random particles	Including Gaussian random particle distribution, Linear random particle distribution, and Uniform random particle distribution.
Toroids	Including Circular toroid, Ellipse toroid, Equilateral n-side polygon toroid, and Partial circular toroid.
Uncategorized structures	Including Helix and Spiral.

Add and Change

Add Built-in Structure Group

You can open the built-in structure groups available in the software, and view the options shown as below:

Edit Built-in Structure Group

Add a structure group in the Cylinders>Gear Cylinder, and open the Edit properties.

The built-in structure group in the software not only enables modification of global parameters (relative position, rotation) or script variables, etc., but also allows users to change parameters of an individual unit within the structure group, or to delete/add a certain structure unit.

Custom Structure Group

Create

The software supports custom structure groups that can be created according to the following general procedures:

Example: Circular Aperture Diaphragm

Based on these procedures, you can create a structure group for a common aperture.

1. Analyze the composition of the components and divide the complex structure into a combination of multiple basic units. For example, the aperture is usually a circular shape on a flat plate. Users can choose the 2D polygon structure to establish the aperture.
2. Add an empty structure group according to the operations shown in the figure:

3. Define the aperture parameters:

4. Write the script on the structure group Script page, including the code as follows:

   deleteall;
   
   # setup variables
   Rin = 0.5e-6;
   Lout = 2e-6;
   res = 100;
   
   
   # setup script
   xin = Rin.*cos(linspace(0,2*pi,res));
   yin = Rin.*sin(linspace(0,2*pi,res));
   xout = [Lout,Lout,-Lout,-Lout,Lout,Lout,Rin];
   yout = [0,Lout,Lout,-Lout,-Lout,0,0];
   V = [xout,xin;
   yout, yin];
   add2dpolygon;
   set("name","2d ring");
   set("vertices",V);
   
   

5. The structure group created is shown in the figure below (the image has been processed):