Diameter 30mm Fused Silica Ball Lens

What is ball lens/ball lenses?

Ball lenses are great optical components for improving signal coupling between fibers, emitters, and detectors. They are also used in endoscopy, bar code scanning, ball pre-forms for aspheric lenses, and sensor applications. Ball lens are manufactured from a single substrate of glass and can focus or collimate light, depending upon the geometry of the input source. Half-ball lenses are also common and can be interchanged with full ball lenses if the physical constraints of an application require a more compact design.

Why use a ball lens/ball lenses？

A sphere or ball performs surprisingly well as a lens. At closer scrutiny, one finds that such an element can be broken down into two plano-convex lenses, separated by a plane-parallel plate. The positive lenses have under-corrected spherical aberration and the plane-parallel plate is over-corrected. Therefore, there is a compensating effect. A ball lens finds its main application as a coupling element for optical fibers. It deserves an analysis, especially since there are certain limitations that need to be understood.

The figure below indicates that the focal length is measured from the center of the sphere, where the extensions of the entering and exiting rays meet. This means that the back focal distance bfl is merely the difference between the focal length and the radius R of the sphere. One can see immediately that the focus falls on the rear surface of the sphere if f = R.

Ball lens/ball lenses we can provide 

Regular specifications of our ball lens.