What is the difference between edge blackened and not edge blackened?
Edge-blackened lenses, or inked lenses, minimize the stray light within an optical system. Stray light in imaging and electro-optical systems can scatter off the ground edges of the lens elements within that system. The scattered light increases the noise which severely limits a system’s ability to reproduce contrast. Coating the edges with a black paint or ink minimizes the scattered light, improving the signal to noise ratio. Many of our Broadband Anti-Reflection (BBAR) coated lenses have been made available as off-the-shelf products with blackened edges. Achromatic lenses are available Edge-Blackened as well as our Plano-Convex, Double-Convex, Plano-Concave and Double-Concave Lenses.