ZEMAX has hundreds of features that cover the vast majority of user needs for optical design and analysis. However, no matter how many features a program has, there always seems to be the need for a custom analysis or computation.

For these cases, ZEMAX offers three different approaches to performing your own calculations.

The first approach is the 1D/2D Universal Plot. This plot looks like a normal ZEMAX calculation window, except that you can define what is on the x and y axes directly.

The independent variables can be any system parameter (wavelength, field, temperature, pressure), or any surface parameter (radius of curvature, thickness etc). The dependent variable can be the merit function, any optimisation operand, or a macro (macros as discussed later on this page).

For example, this 2D universal plot screenshot shows the variation in power (W/mm^2) with front and back radius of curvature for a singlet lens in NSC. But it could just as easily show how MTF varies with the conic constant on surface 5, how spherical aberration varies with aperture, or many, many other features.

The next approach is the macro. Macros use a simple, BASIC-like   language called the ZEMAX Programming Language (ZPL). ZPL uses simple BASIC-like commands such as PRINT and GOTO, and also addsan extensive library of  new keywords such as RAYTRACE and GETMTF that can be used to extract data computed by ZEMAX.

A typical macro

ZPL supports inline function calls, user defined variables, text and graphical output, and a simple interface to the ray tracing algorithms. ZPL macros can read and write ASCII files to format custom data reports. It is ideal if the information you need can be quickly calculated from ray-trace data.

The third, and most powerful technique is to write your own program to control ZEMAX. ZEMAX is designed to operate in a client-server architecture; with ZEMAX being the server, and any other Windows program being the client. ZEMAX can be used to load existing or create new lens files, trace rays, and optimize, all under the transparent control of an external program.

One application for this technology is the extension of ZEMAX with user written programs to provide a user defined feature capability. These features are tightly integrated with the ZEMAX user interface. The extended features appear as menu items, and output is displayed as a standard ZEMAX feature.

Alternatively, the client-server architecture can be used for a third party program that only needs the ZEMAX server, and not the ZEMAX interface or graphics.

In either case, the programming language is C or C++ and all the power and flexibility of the common programming development tools are available.

Using C, you can write your own analysis features, optimization operands, optical surfaces and sources. This gives you total control over every capability in the program.