OFG / PLG - Optical fibers and fiber plug adapters

In order to connect the measurement head or optical probes to the spectrometer, Instrument Systems supplies a range of optical fiber guides (OFG-xxx). These are not attached directly to the spectrometer, but instead to a fiber plug adapter (PLG-xxx) appropriate for each fiber type. The fiber plug adapter is then mounted on the spectrometer's entrance port. This innovative concept means that calibration of the spectrometer remains intact when changing the accessories attached.

Optical fibers and fiber plug adapters

Properties of the different fiber guides:

Type FeaturesAdvantages Application
multimode fiber with SMA connectormultimode fiber with core diameter 200 - 1000 µmsuperior light transmission for small beam diameterscollecting and transmitting collimated light
fiber bundle with ferrule bundle of fibers each with core diameter of 50 µm large cross sections possible; bending the fiber does not affect transmission  collecting and transmitting diffuse light

Ordering information for fiber guides:

ModelDiameterSpectral rangeFeatures
Multimode fiber with SMA connector
OFG-311 / -312 / -313200 / 600 / 1000 μm300 - 2200 nmglass fiber
OFG-321 / -322 / -323200 / 600 / 1000 μm 190 - 1350 nm quartz glass fiber
OFG-352 400 μm 1000 - 6000 nm chalcogenide fiber
Fiber bundle with SMA connector
OFG-343 1 mm 280 - 2500 nm LIR fiber
Fiber bundle with ferrule
OFG-414 / -4151.5 / 3 mm 380 - 1600 nm glass fiber
OFG-424 / -425 1.5 / 3 mm 190 - 1350 nm quartz glass fiber
OFG-444 / -445 1.5 / 3 mm 280 - 2500 nm LIR fiber
OFG-464 / -465 1.5 / 3 mm 190 - 2500 nm mixed fiber bundle
Bifurcated fiber bundle with ferrule; 2 arms combined to 2.1 mm Ø

1.5 mm 190 - 1350 nm quartz glass fiber
OFG-554 1.5 mm 190 - 1600 nm mixed fiber bundle
OFG-555 1.5 mm 190 - 2500 nm mixed fiber bundle
Fiber bundle cross section conversion
OFG-625 3.6 mm 190 - 1350 nm changes cross section to 2 x 5 mm

Instrument Systems supplies appropriate connector adapters for both multimode fibers and fiber bundles. Fiber plug adapters are also available for all popular connectors as used in optical telecommunications and fiber sensor applications.

The fiber plug adapter slides into the optical input of the spectrometer and is fixed with the knurled ring. An alignment pin guarantees accurate and reproducible installation. Furthermore, the fiber plug adapter ensures efficient coupling of the light into the spectrometer due to the integrated lens that matches the fiber NA (numerical aperture) to the f-number of the spectrometer.

Ordering information for fiber plug adapter PLG:

SMA connector Fiber bundle ferruleSpectral rangeTransmission
PLG-310 PLG-410 300 - 2200 nm optimized for VIS
PLG-320 PLG-420 190 - 3200 nm optimized for UV
PLG-340 PLG-440 190 - 3200 nm optimized for IR
PLG-350 n/a 1000 - 5000 nm optimized for IR

Additionally, the PLG adapters of the type PLG-53x are compatible with the connectors popular in optical telecommunications: FC/PC, ST, DIN, Radiall, Diamond.