In binoculars, ED (extra-low dispersion) glass (also sometimes referred to as a high density - HD - glass) is a high quality optical glass that increases light transmission, decreases light dispersion, and so cuts down on chromatic aberration, or "color fringing", which is due to the splitting of the light spectrum. It is used in binocular objective lenses to help focus the light waves of the color spectrum on the human eye, and to deliver bright, sharp images. ED lenses are composed of a specific formulation that contains rare-earth elements.
LUXUN 12x50mm ED Lens Binoculars
Description: Six advantages: BAK4 prism, high-definition high magnification, low light level night vision, ED lens, 50mm large objective lens, IPX-6 waterproof grade 1. Large eyepiece, large field of vision: 28mm large eyepiece, wide field of vision, comfortable to watch. 2. ED lens, Extra low Displacement, sharp and transparent imaging. 3. Prism high dielectric coating, high light transmittance. 4. IPX-6 waterproof grade
