Conventional microscopes have a very limited depth of focus.   Test surfaces  and features are clearly visible ONLY when they are within the focal depth . The Zeta system scans a sample over a user specified vertical (or Z) range. At each Z position, it records the XY location and the Z height of the pixels that are in focus.  This information is used to create a true color 3D image and a 2D composite image.  The resulting image has a extended depth of focus so the entire surface is seen clearly. The Zeta 3D software can be used to ascertain dimensional and roughness information.