EDF Macro Imaging

Imaging at large magnification traditionally has meant imaging with a very small depth of field or imaging with a very small aperature/large F/#. Often, the depth of field at a certain magnification is far less than the depth of the object being imaged. The above image offers an example of the limited depth of field related to traditional macroscopic imaging.

With optical/digital focus-invariant imaging systems, the depth of field can essentially be an independent parameter in the design of the imaging system. The depth of field can be selected and designed independent of the system magnification, F/#, etc. Move your mouse over the above image to view the focus-invariant color macro image. The illumination, exposure,geometries, scales, etc. are all identical to the traditional system.

The spatial resolution of the focus-invariant system is as good or better than the image from the traditional system for all points of the image. The image from the focus-invariant system is also in focus over the entire image. Since a focus-invariant system is a general aberration-invariant system, the negative effects of a number of aberrations on the final image are automatically corrected.