Fiber Optic Cable

Signal stability and low noise in remote spectroscopy depend upon fiber optics with high transmission. The transmission must be affected very little by environmental influences such as temperature, vibration, and ambient light levels. From a patented fiber design to our emphasis on high-quality materials, Guided Wave spectroscopic grade optic cable is designed for the highest performance in transmission efficiency and durability. A polyimide coating and a patented silicone based buffer protect the fiber. Some of our fiber optic cable products also receive a tough outer jacket made of Tefzel™ and inner Kevlar™ strands for strength. 200 micron telecommunication grade fiber optic cables are not appropriate for spectroscopic applications, as they cannot bring enough light to the detector. Guided wave supplies 400, 500, and 600 micron fiber optic cables. The NIR-O and Clearview are optically matched to 500 micron, as it provides the best compromise between flexability for installation and light throughput.

Manufacturing High Performance Fiber

All Guided Wave optical fiber is constructed as a core-and cladding composite. The core – the filament that guides the light – consists of a thin strand of high-transmissivity fused silica. The cladding is an outer layer of doped, lower refractive index fused silica. This two-layer design keeps the light tightly confined to the central core of the fiber thus delivering a maximum amount of light at the far end. The diameter is tightly controlled during the drawing process. This produces a fiber that centers extremely well in connectors and has a very low loss rate per kilometer.

Unprotected silica fiber is quite fragile. To improve the fiber’s strength and flexibility, it is coated with a polyimide material during the drawing process. Then, another protective layer is added, a carbon-loaded buffer of silicone RTV (U.S. Patent #5,381,505). The buffer reduces stray light, both external ambient light that “leaks” through the jacket and internal stray light or “cladding” modes. Finally, we add an outer protective jacket. Our “process fiber” – fiber optic cable for harsh environment applications or applications requiring long cable runs – receives a multi-layer jacket made of Tefzel™ and Kevlar™. Our “laboratory fiber” – intended for short laboratory-bench runs – can be supplied in PVC-coated steel monocoil jacket, steel armored BX jacket, or PVC-zip tubing.

Jacketing Options

  • Process fiber cable: Tefzel™-Kevlar™
  • Laboratory fiber cable: PVC-coated, steel monocoil jacket
  • Armored fiber cable: Steel BX Armor with PVC Jacket (150 meter max length)  - contact Guided Wave for alternative lengths

Available Diameters – Core/Cladding/Polyimide

  • 200/220/239 μm (15 meter maximum length)
  • 400/440/480 μm
  • 500/550/590 μm
  • 600/660/710 μm
Fiber optic cable esigned specifically for NIR, UV-VIS spectroscopy

Two Kinds of Fiber Cable

Presently, Guided Wave offers two different kinds of optical fiber optimized for your spectral region of interest. Each type can be jacketed as outlined above and terminated in SMA, ST, or FC style connectors. Cables and bare fiber are available in a variety of core diameters from 200 μm to 600 μm (contact Guided Wave for alternatives). The type of cable you’ll choose depends on your application:

• Ultra Low-OH fiber provides the lowest possible amount of internal light attenuation. It is appropriate for visible or near infrared (Vis/NIR) spectroscopy. It is especially effective for
applications that require increased sensitivity in the spectral region near 1385 nm or where very long cables are necessary (> 150 m). This cable is effective over the spectral range from
400 nm to 2100 nm.

• Deep UV (UV-SR) fiber is intended for spectroscopy in the ultraviolet and visible (UV/Vis) regions – 200 nm to 800 nm. Typically, to avoid high attenuation, cable length is kept short, < 50 m. SR stands for solarization resistant. Fiber that is exposed to UV light forms f-centers which reduce the transmission of the fiber.

Fiber Termination Options

  • SMA 905
  • FC
  • ST
  • Custom (call)
  • Bifurcated (call)
  • Unterminated

Optional Accessories

  • SMA 905 and FC Bulkhead Unions
  • SMA 905 to FC Adapter, ST Adapter
  • Fiber Termination Kit and accessories
  • Calibrated torque wrench for SMA 905 connectors

Figure 1: Guided Wave Process Jacket Fiber Optic Cable Anatomy

Guided Wave Process Jacket Fiber Optic Cable Anatomy

Figure 2: Performance Characteristics of Guided Wave Fiber

performance characteristics of  Guided Wave fiber

Specifications: Fiber Optic Cable

Product NameUltra Low-OH FiberDeep UV Fiber (UV-SR)
Product Part Number
Wavelength Spectral Range400-2100 nm 200-850 nm
Application Typical VIS-NIRUV-VIS
Fiber Run Typical (Length) 10 to 250 m < 50 m
Temperature Maximum - Bare or Armored (If High-Temp Epoxy is used for termination)315 °C 315 °C
Temperature Maximum - Tefzel Jacket (If High-Temp Epoxy is used for termination)165 °C 165 °C
Temperature Maximum - PVC (If High-Temp Epoxy is used for termination)105 °C105 °C
Temperature Minimum (Contact Guided Wave for alternatives) -20 °C -20 °C
Core to Cladding Ratio Core Ø ≥ 200 μm 1:1.1 January 1, 1970
Numerical Aperture (NA) 0.22 ± 0.02 0.22 ± 0.02
Diameter Core Tolerance Core Ø ≥ 200 μm ± 1.5% x Cladding Ø ± 1.5% x Cladding Ø
Diameter Tolerance Total(Polyimide) ± 10 μm ± 20 μm
Baseline Attenuation (Unjacketed) ≤ 3 dB/km @ 1550 nm < 50 dB/km @ 380 nm
Attenuation Difference (1385 nm – 1550 nm) < 5 dB/km NA