Geordi Laforge

Geordi Laforge is the Chief Engineer aboard the Enterprise-D, although he began the TNG series as a member of the bridge crew.

He was born completely blind. His eyes appear to be solid white with no sign of pupil, iris or lens. To compensate, he wears a VISOR which actually allows him to see a far greater range of EM-frequencies than normal eyes would.

Riker (while possing Q powers) restored Geordi's sight once but he immediately asked Riker to reverse the process. He wore the visor through the TNG series, including the first TNG film, Star Trek: Generations. Sometime after, he had the device replaced with more natural appearing "eyes" as seen in Star Trek: First Contact. The metaphasic radiation in Star Trek: Insurrection appears to have caused real eyes to grow, supposedly eliminating the need for artificial implants all together. There is no evidence either way in Star Trek: Nemesis although his eyes in the film are not the same color they were in Insurrection or when Riker restored his sight in "Hide and Q" (brown). The color seen in Nemesis does seem to match that seen when we see him in the future in "All Good Things" or the Voyager episode "Timeless" (blue-grey).