| Certain magnifiers have lens systems which
correct optical distortion or aberration that might otherwise |
| • Distortion
Uncorrected lens - "straight lines" curve toward
center |
| • Chromatic
and Spherical Aberration Uncorrected lens-size
and shape differences occur in a pattern |
| consisting of one size dot. |
| Achromatic......................................................................Lens
that eliminates chromatic aberration. |
| Aplanatic..........................................................Lens
that corrects for spherical aberration and coma. |
| Chromatic Aberration..........................Inability
of a lens to focus light of different colors at a point. |
| Coma........................................Blurry
appearance around an object viewed through uncorrected
lens. |
| Corrected................Lens
system that corrects for distortions and aberrations to
produce a sharp image. |
| Spherical Aberration......................................Lens
defect that produces an image that lacks contrast. |
