Related Clues:

• Eyepiece, in jargon
• Eyepiece
• Telescope part
• Eye-related
• Pertaining to the eyes
• Microscope part
• Of the eye
• Visual
• Relating to the eye
• Vision-related
• Done by sight
• Visionary?
• Of the eyes
• Pupil-related, maybe
• Eyesight-related