reTORT Graphing Wizards
Graphing a variety of lens metrics is a critical part of using reTORT. This is true for any optical system analysis. In fact, this is so for any electromagnetic analysis. To ease the graph-generating process, reTORT provides wizards for the most common plots used by lens designers. These plots include spot diagrams, wavefront error plots, MTF graphs, and TRA traces.
Running the reTORT Wizards
To open a graphing wizard, you only need to right-click on a reTORT simulation in the GEMSIF Model Hierarchy dock. Next, open the Tools submenu. You can also do this by selecting the reTORT simulation in the Model Hierarchy dock. Next, click on “Tools” in the menu-bar at the top of the window. The options in the Tools menu allow you to create:
- Spot Diagram
- Wavefront Error Plot
- Modulation transfer function of MTF Graph
- TRA Trace
Graphing Wizard Options in reTORT
Click on the Tools option for the wizard of your choice. A popup dialog will appear asking for details about the plot you wish to create. Here, you can control the focal plane at which the metrics are computed. It also specifies the types of ray-bundles displayed in the graph.
1. Optical Output
This option selects the optical output used to compute the plotted metric. Most importantly, this controls the focal plane used to compute the metrics. Selecting “Create New Output” will generate a new optical output with a focal plane at the minimum RMS spot size of the rays.
2. Optical Source
Here, the source whose rays will be displayed in the diagram is selected. If you select “All Sources”, then the diagram will include rays from all sources in the simulation.
3. Wavelength
This option selects the wavelength to include in the graph. The diagram will include ray-bundles at the specified wavelength. If you select “All Wavelengths”, then ray-bundles of any wavelength will be shown in the plot.
4. Incident Elevation Angle
I this dropdown, you select the incident angle to display in the graph. The diagram will include ray-bundles matching this elevation angle. If you select “All Angles”, then ray-bundles of any angle will be included.
5. Trace Axis
This is only available to you for the MTF and TRA plots. This option controls whether the MTF/TRA is plotted over the meridonal plane, the sagittal plane, or both.
Once you have selected the options you want, click the OK button to generate the plot.
Spot Diagrams in reTORT
The reTORT spot diagram wizard generates a plot showing where each ray intersects the focal plane. It also displays the diffraction-limited airy disk for the lens system. Rays and airy disks of different wavelengths are rendered in different colors.
reTORT Wavefront Error Plots
The wavefront error wizard generates a contour plot of the wavefront error at the selected focal plane. If you select multiple ray-bundles, then each ray-bundle is displayed as a separate plot in the same window.
reTORT MTF Graphs
You can choose graphs generated by the MTF wizard to display either a meridonal MTF trace, a sagittal MTF trace, or both. MTF is the modulation transfer function. It also displays the diffraction-limited MTF curves. Different ray-bundles are traced in different colors.
reTORT TRA Traces
The TRA wizard creates ray-fan plots in either the sagittal plane, the meridonal plane, or both. The TRA traces of different ray-bundles are displayed in different colors.
