Fiber optic cable (FOC)

What is called optical fiber cable (FOC)?

FOC are optical fibers. Fiber optics transmit data in the form of light signals at high speeds over long distances.

They can be made of plastic or glass, the latter is called fiberglass. Optical fibers are therefore electrically non-conductive. The optical fibers are very flexible, but they can break if they are bent too much. For this reason, professional laying is essential. The optical fibers are covered with a plastic layer that protects them.

The optical fibers can transmit light signals of certain wavelengths. Fiber optic speeds depend on the type of cable used. A distinction must be made here between single mode and multimode. The differences lie mainly in the fiber core diameter, the wavelength, the light source and the bandwidth.


Singlemode has a very small core (9µm) that only allows one type of light. This means that the attenuation is very low and offers the advantage of using this optical fiber over longer distances.

ULL glass fibers – the special single mode

ULL fiber has the lowest attenuation of all single-mode fiber. It is successfully used worldwide where the requirements are ultra-low attenuation. This latest low-loss fiber optic technology offers lower maintenance costs and can transmit more data over longer distances. The fiber optic is actually not influenced by external environmental conditions (desert, rainforest, water, heat). Here too, we can offer splicing and measuring services thanks to our high-quality equipment.


Multimode hat einen größeren Kern. Heute haben diese einen Kern von 50 µm, es gibt ältere Multimodefasern mit 62,5 µm. Größere Kerne bedeuten auaMultimode has a larger core. Today these have a core of 50 µm, there are older multimode fibers with 62.5 µm. Larger cores mean on the one hand more data transfer, on the other hand more light refraction, which means higher attenuation. Therefore, multimode is more likely to be used for shorter distances.f der einen Seite mehr Datenübertragung, andererseits mehr Lichtbrechung, was eine höhere Dämpfung bedeutet. Von daher benutzt man Multimode eher für kürzere Strecken.
We offer measurements in the 62.5 µm range.

How do you process and connect fiber optic cables?

The so-called splicing

Special devices, so-called splicing devices, are required to process the extremely thin fibers. In our company we work with high-quality equipment from Fujikura. Using appropriate devices and light coupling, the glass fibers are brought together precisely and then connected using arc welding, the so-called splicing of the glass fiber.

What are splice boxes?

Fiber optic splice boxes are required for splicing fiber optics. Here the glass fibers are brought together using pigtails. Pigtails are optical fibers with an assembled connector. Fiber optic splice boxes are available in a variety of designs, e.g. as a sleeve for underground installation, as a surface-mounted housing and the most common variant as a 19″ splice box, usually with 1 U (height unit approx. 45 mm high). Fiber optic splice boxes are available with various connector outlets, the most common fiber optic connectors are ST / SC / LC and E 2000.

Do you know the hydrogen content (water peak) in your fiberglass?

Hydrogen oxide is embedded in glass fibers. Due to water atoms or molecules, impurities occur and the OH peak occurs. This causes significantly higher attenuation at certain wavelengths. These include 945 nm, 1240 nm and 1383 nm.
The wavelength of 1383 nm is particularly relevant for single-mode fiber optics. The older single-mode fibers are particularly affected. There are now so-called “low water peak” fibers. In these fibers, the OH peak in the wavelength 1383 nm could be strongly suppressed by changing the index profile. If signals are to be transmitted in this area, it is recommended to measure the transmission properties. Special ODTR modules are available for this, which contain a special laser for 1383 nm.
We have devices to measure hydrogen content in the fiberglass.