| Answer | Crossword Clue |
|---|---|
| aplanat | an distortion-free lens |
| aplanats | APLANAT, an distortion-free lens |
| pincushion | A form of optical distortion in which straight lines along the edge of a screen or a lens bulge toward the center |
| pincushions | A form of optical distortion in which straight lines along the edge of a screen or a lens bulge toward the center |
| HIFI | Distortion-free |
| OPTI | ..-Free: contact lens solution |
| aplanatic | of a lens, free of spherical aberration |
| aplanatically | APLANATIC, of a lens, free of spherical aberration |
