Biconvex lens 

A double-convex lens is compose of two convex surfaces, has a positive focal length. Normally Bi-Convex lenses are most suitable where the object and image are on opposite sides of the lens, and are popular for many imaging applications.
Changchun Yutai optics Co.,Ltd can customized biconvex lens as request and also have many kinds of stock lens to choose.(daisy@yt-optics.com)
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