Equipment of the Photonics Laboratory


The Photonics Laboratory has established a wide range of high level equipment for various fiber sensing applications, including fiber processing, fiber Bragg grating (FBG) manufacturing and calibration devices.


FBG Manufacturing

Laser source:
MLI-200KrF FBG, MLase AG, Germering (Germany)


FBG Inscription Facilities

Excimer-laser at 248 nm and phase mask technique

  • Uniform and pi-shifted FBG gratings (length: 1 mm to 2 cm)
  • Sensor arrays with predefined spatial distance (11 phase masks with periods between 1046 nm and 1091 nm)
  • FBGs in different types of fibers: Fibers with different cladding diameters (80 µm to 250 µm), singlemode fibers, polarization maintaining fibers and photonic crystal fibers
  • Inscription in hydrogen-loaded and highly germanium-doped fibers

High pressure hydrogen chamber:
FMB Feinwerk und Messtechnik GmbH, Berlin (Germany)


Hydrogen Loading Facility

High pressure hydrogen chamber

  • Hydrogen loading is used to increase the fiber's photo-sensitivity for FBG inscription
  • Used for the fabrication of regenerated FBGs, FBGs with high reflectivity and FBGs in fibers with a low germanium concentration in the fiber core.

FBG Calibration

Four point bending setup:
Munich University of Applied Sciences, Munich (Germany)


Strain Calibration Facility

Four point bending: -1000 µstrain to 1000 µstrain

  • 4-point bending beam (1300 mm, 30 mm, 30 mm) for strain calibration: Munich University of Applied Sciences, (Germany) (self-construction)
  • Accurate displacement detection at three points on the surface (HMT2571), Dr. Johannes Heidenhain GmbH, Traunreut, (Germany)
  • Calibration range: approx. -1000 µstain to 1000 µstrain
  • Accuracy: approx. 0.15 %
  • Complaint with VDI/VDE 2660 guideline

Hydrogen calibration facility:
Munich University of Applied Sciences, Munich (Germany)


Hydrogen Calibration

Custom-built hydrogen calibration below 2 vol. %

  • Hydrogen concentration range between 40 ppm and 20000 ppm
  • Flow-accuracy: 1 % of the full scale
  • Calibration in nitrogen or dry air
  • Hydrogen calibration at temperatures between 10 °C and 50 °C
  • Modular design

High temperature furnace:
ROS 20/250/12, IBF Industrie Beratung Finkel, Nürnberg (Germany)


Temperature Calibration

Several furnaces with a total temperature range between -40°C and 1200°C

  • Climatic chamber: VCL 4010, Vötsch / Weiss Umwelttechnik , Balingen (Germany),
    temperature range: -40°C to 170°C
  • High temperature calibration furnace: Isotech Pegasus Plus 1200 S, Isothermal Technologie Ldt. Merseyide (Great Britain),temperature range: 150°C to 1200°C
  • High temperature tube furnace: ROS 20/250/12, IBF Industrie Beratung Finke Nürnberg (Germany),
    temperature range: 100°C to 1200°C
  • Reference furnace near room temperature, Munich University of Applied Sciences, Munich (Germany) (self-construction), temperature range: 5°C to 40°C
  • High-temperature micro-furnace, Micropyretics Heaters International, Redna Terrace (USA),
    temperature range: 400°C to 1800°C

FBG Evaluation

optical sensing instrument:
FAZ I4, FAZ Technology Ltd., Dublin (Ireland)


FBG Interrogation

Scanning laser systems (FBG wavelength multiplexing)

  • Spectral FBG evaluation: Bragg wavelength determination with a peakfit algorithm as post process or internal wavelength determination
  • Utilisation of fully polarization resolved measurements
  • High precision interrogation: FAZ I4, FAZ Technology Ltd., Dublin (Ireland), wavelength range: 1530 to 1565 nm, sweep rate: 1KHz, wavelength repeatability: 0.5pm @ 1KHz
  • Interrogation in a wide wavelength range: si255, Micron Optics, Atlanta (USA): Wavelength range: 1460 to 1620 nm, scanning frequency: 10 Hz, wavelength repeatability: 1 pm, 0.3 pm at 1 Hz
  • Standard interrogation: sm125, Micron Optics, Atlanta (USA), wavelength range: 1510 to 1590 nm, scanning frequency: 2 Hz, wavelength repeatability: 1 pm at 2 Hz

Optical spectrum analyzer:
Advantest Q8384, Anritsu, Tokyo (Japan)
Amplified spontaneous emission (ASE):
HM Munich (Germany)


Spectral Analysis

Optical spectrum analyzer

  • Optical spectrum analyzer: Advantest Q8384, Anritsu, Tokyo (Japan), wavelength range: 600 to 1700 nm, accuracy: ≤±20 pm 1530 to 1570 nm, ≤±40 pm 1570 to 1610 nm, linearity: ≤±10 pm (1530 to 1570 nm), ≤±20 pm (1570 to 1610 nm), repeatability: ≤±3 pm (1530 to 1610 nm)
  • Broadband light source ASE (Amplified spontaneous emission): self-construction Munich University of Applied Sciences, Munich (Germany), wavelength range: 1525 to 1570 nm , output power: 25 mW


Fiber Processing and Testing

Filament Splicing Unit:
LFS4000, Vytran Thorlabs UK Ltd, Exeter (Great Britain)


Fiber Splicing, Cleaving and Recoating

Arc-charge and filament splicing units

  • Utilization of transmission controlled splices of single mode and polarization maintaining fibers enables thoug Filament splicing with possibility of azimuthal alignment of the fibers: LFS 4000, Vytran Thorlabs UK Ltd, Exeter (Great Britain)
  • Splices with different fibers and with special fiber types:
    Diameters: 80µm to 2mm
    Fiber types: single mode, polarization maintaining and photonic crystal fibers
    Fabrication of fiber packaging, such as spliced capillaries
  • Fusion Splice Systems: OptiSplice LID (Corning Cable Systems, Munich (Germany): Quick and easy splices of single-mode fibers
  • Fiber Cleaver: LDC400, Vytran Thorlabs UK Ltd, Exeter (Great Britain)
  • Fiber Recoating: SS541, Fitel / Furukawa Information Technologies and Telecommunications, Tokyo (Japan)

SMF28, Corning Cable Systems,Munich (Germany)


Fiber Testing

Optical and mechanical fiber characteristics

  • Attenuation properties of fibers and splices: OTDR measurements, MU100021A, Anritsu, Kanagawa (Japan)
  • Polarization properties of fibers and optical components: Polarization maintaining properties (Extinction Ratio, Degree of Polarization), polarization states (Stokes Vectors), polarization controlling: Tunable Laser Source 8163B and polarization controller N7788B, Agilent Technology, Santa Clara (USA)
  • Testing facility for tensil strength of fibers

Coupler Workstation
Fiberforge FF-280,Lightel, Renton (USA)


Fiber Coupler Development and Fabrication

Forging tool for fiber optics

  • Manufacturing of standard / novel fiber components
  • Manufacturing of 2x2 standard fiber couplers
  • Manufacturing of 2x2 high temperature fiber couplers