A configuration is a variant of a basic optical system in which one or more defining parameters take on different values. Virtually any parameter in Zemax, such as a wavelength, aperture value, field position, radius, thickness, glass type, object parameter or other data, may take on multiple values. Each configuration may have different values for many different parameters.
This feature can be used to design conventional zoom lenses, scanning systems, athermalized lenses, multiple path systems, interferometers, lens arrays, beamsplitters and more.
Zemax can draw one, a specified sub-set, or all configurations of a system on one plot, either displaced or overlayed at any point in the optical system. Global reference coordinates make it easy to link the locations of various components in the system to one another across configurations. Here a galvanometer-style mirror scans a laser beam over the pupil of
Simultaneous optimization of multiple configurations is also supported. Zemax supports zoom lens analysis and design as a special case of the more general multi-configuration concept. Each configuration may have identical or different merit functions. Variables and constraints may be common to all configurations or unique to just a few. This powerful feature may also be used to athermalize an optical system by simultaneously optimizing over a range of temperatures.
Here for example is an afocal zoom from Zebase. Many low-power microscopes, used in inspection, as surgical microscopes, in electronic assembly etc use an afocal 'pod' as a means of obtaining the zoom. This has the advantage of allowing the manufacturer to make modular components, where the objective, eyepiece and prism assembly are all the same as on the fixed-power unit, and the afocal pod is inserted by the user to zoom. This particular system has a zoom ratio of 4:
It can be seen that some lenses change position while others are static. Here is a simple object scene viewed through the lens at each zoom position, with the zooms superimposed for easier comparison:
Related Knowledge Base articles:
How to Model an Adaptive Optical System
How To Model a Scanning Mirror
How to Model a Beam Splitter in Sequential Zemax