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561-740-2525 • Fax 561-740-2518
sales@TowerOptical.com • www.TowerOptical.com
Cage Code: 1N2U3 SDVO-SB ITAR Compliant
Dia.
L
Ball and Drum Lenses
Specifications
Material: BK7 grade A or equivalent or
UV fused silica
Diameter tolerance: ±0.01 mm
Sphericity: ±0.003 mm
Surface quality: 40-20 Scratch-Dig
Coating: none
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 1.0 mm to 5.0 mm. 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
Ball Lens Material Model Price
Diameter Number
1.0 mm BK7 LB1-001 $22
2.0 mm BK7 LB1-002 $21
3.0 mm BK7 LB1-003 $20
4.0 mm BK7 LB1-004 $20
5.0 mm BK7 LB1-005 $22
1.0 mm UV FS LB2-001 $34
2.0 mm UV FS LB2-002 $28
3.0 mm UV FS LB2-003 $28
4.0 mm UV FS LB2-004 $28
5.0 mm UV FS LB2-005 $30
6.0 mm UV FS LB2-006 $41
8.0 mm UV FS LB2-008 $43
10.0 mm UV FS LB2-010 $58
Pricing and ordering info
Drum Lenses
Model No. Diameter Length Price
LD1-020-025 2.0 mm 2.5 mm $30
LD1-020-030 2.0 mm 3.0 mm $30
LD1-020-040 3.0 mm 4.0 mm $31
LD1-020-050 4.0 mm 5.0 mm $31
Specifications
Material: BK7 grade A optical glass
Diameter tolerance: +0.0/-0.05 mm
Length: ±0.01 mm
Surface quality: 40-20 Scratch-Dig
Coating: none
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.
Pricing and ordering info
LD2-XXX-yyy is Fused Silica drum lenses. Contact factory for pricing.
D d
EFL
BFL