The fastest way to get help is directly inside the software interface. Pressing on your keyboard instantly opens the context-sensitive help section relevant to the specific tool, tab, or dialog box you are currently using. The Ansys Help Portal
The manual frequently references built-in sample files located in your Documents\Zemax\Samples folder. Always open these files alongside the text to see the concepts live. zemax user manual
However, the industry still commonly searches for the "ZEMAX user manual" because: The fastest way to get help is directly
Sequential ray tracing, non-sequential ray tracing, and physical optics propagation (POP). non-sequential ray tracing
to avoid designing unbuildable optics.