Ball lens Tower Optical

Ball Lenses

Ball lenses are used for various tasks such as improving the coupling between optical fibers and the emitters or detectors they interface with. Standard size lenses range from 1.0mm to 5.0mm. Custom-made sizes or special materials are also available. All Ball Lenses can be ordered with full-surface anti-reflection (AR) coating..

The effective focal length of a ball lens is given by the following formula:

BFL = F – D/2 and EFL = nD/4(n-1)

The Numerical Aperture, NA, of a ball lens is dependent on the focal length of the ball and on the input diameter, d.

NA = 2d(n-1)/nD

Specifications

Material: BK7 grade A optical glass

Diameter tolerance: ±0.005mm

Sphericity: ±0.003mm

Surface Quality: 40/20

Coating: none


Drum Lenses

A Drum Lens is a variation of a ball lens where a portion of the ball is ground down to a smaller diameter. These lenses are used in similar applications to those of ball lenses. The drum lens adds the ability to handle and package it in a different way.


Specifications

Material: BK7 grade A optical glass

Diameter tolerance: +0.0/-0.05mm

Length: ±0.005mm

Surface Quality: 40/20

Coating: none

More specifications...