Functional Principle

• fast and trouble-free use
• highly compact design
• low weight
• low insertion loss
• low back reflexion
• for the visible spectral range (400-700 nm)
• achromatic lenses
• excellent beam quality with low wavefrontdistortion (diffraction-limited imaging)
• for singlemode and polarizationmaintaining fibers

To collimate the divergent beam emitted by a fiber, the end surface of the fiber must be positioned exactly in the focusing plane of the lens. The diameter of the collimated beam dS and the angle of divergence α depend on the focal length f of the lens, on the core diameter dk and on the numeric aperture NA of the fiber (see drawing on beam collimation below).

LINOS offers three versions of fiber collimators:

Fiber collimator FOC10 Z has a diameter of 10 mm and a length of 19.5 mm. The lens can be optimized to meet specific customer requirements by using the focusing key supplied with the collimator.

Fiber collimator FOC12 has a diameter of 12 mm and a length of 50 mm. It is available only in conjunction with a fiber optic cable as beam collimation and the position of the beam axis to the housing are specially adjusted to the particular fiber. Here, a concentricity of ≤ ± 0.5 mrad and anexcentricity of ≤ ± 150 μm are attained. When polarizationmaintainingfibers are used, the direction of polarization of the light emitted is identified by a red dot on the housing.

Fiber collimator FOC16 Z has a diameter of 16 or 18 mm and a length of 30 mm. The lens can be optimized to meet specific customer requirements by using the focusing key supplied with the collimator. The adjustment possibilities allow to align the position of the beam axis of the collimated beam to the mechanical axis of the housing. Thanks to the outer diameter of 16 mm the FOC16 Z can be mount directly into LINOS Nanobench without any adapters.