Wide angle 50 degrees, 6-element optics that include two elements crafted from special ED glass to reduce chromatic aberration to a minimum.

Long eye relief and large 28mm diameter eye lenses (the lens nearest the eye) and soft, fold-down silicone rubber eyecups, provide an exceptionally comfortable viewing experience, for all users, including spectacle wearers. Advanced fully broadband multi-coatings ensure reflection effects are reduced to a minimum level.

All Rigel ED eyepiece models are parfocal.