Wells Research & Development

Library

Technical Library and FAQs

Tests and Configurations

Common Configurations

Measuring Image Quality

Other Measurements

Measuring EFL

Measuring BFL/FFL

Measuring Magnification

Measuring Astigmatism

Measuring Axial Color

Measuring Lateral Color

Measuring Distortion

Measuring Field Curvature

Other Measurements

Measuring Lateral Color

Lateral color is not generally present on-axis. Consider a white square on a black background, close to the edge of the FOV of the lens. Lateral color will cause one edge of the square to have a blue fringe, and the opposite edge a yellow fringe. The magnification of the lens is not exactly the same for all colors.

Measuring Lateral color

Set up for operation off-axis. Use a reticle with a feature whose location is easily measured.
Starting with one narrow band filter, adjust stage for best focus
Use the Feature Location tool to measure the location of the feature
Change narrow band filters

The OpticStudio hardware is rigid enough that you will not disturb the setup by swapping filters, or even reticles. On the other hand, common sense is essential: a firm knock on the system may indeed disturb the setup.
Note the change in location of the feature.

This measurement is especially easy if you press the "set zero reference" button when the first filter is in place.