Glass ball lenses are always used for fiber coupling. to couple light from one fiber optic to another fiber optics of similar NA, two identical ball lenses can be used. Place two ball lenses at the back focal length from the fiber. If the optical fibers have the same NA, then the same logic can be applied.

Glass ball lens is our regular optics too, we started to produce glass ball lenses since our factory was established. so we have very rich experience for production of ball lenses. the diameter we do is from 1mm to 8mm. but we could not coat the ball lenses.

Here is a list of glass ball lenses we have in stock:
Diameter: 1.5mm, 2mm, 2.15mm, 2.3mm, 2.5mm, 2.55mm, 2.75mm, 4mm, 5mm and 6mm
Materials for the ball lenses are BK7, S-LAH64, N-LASF44, H-LAK7, LASFN9 and N-SF8.
Surface quality: 40-20
Diameter tolerance: +/-0.005mm

Payment terms: T/T

Delivery: by DHL express or UPS.