Fiber Fabry-Perot Tunable Filter and Scanning Interferometer
Specifications for Scientific Applications

• Center Wavelength:
  • 400 to 1620 nm
    
• Bandwidth:
  • 50 kHz to 9,000 GHz
    
• Finesse:
  • 5 to 20,000
    
• Free Spectral Range:
  • 10 MHz to 45,000 GHz
    
• Loss:
  • to less than 1.0 dB
    
• Other options:
  • polarization maintaining filter
  • specialty fiber
  • PZT mechanical tuning
  • TEC thermal tuning
    

Chameleon Thin Film Tunable Filter
Specifications for Scientific Applications

• Center Wavelength:
  • 800 to 1650 NM
    
• Bandwidth:
  • 25 to 1000 GHz
    
• Loss:
  • to less than 1.0 dB
    
• Other possible options:
  • polarization maintaining fibers
  • manual tuning
  • high-speed mechanical tuning

FFP components have been fabricated for a wide range of applications in various spectral regions, from 400 NM violet to 1.6 µm IR. FFP-TFs have a micron-size air-gap for wavelength tuning, and generally have bandwidth >1 GHz. FFP-SIs have cavity lengths >20 mm, and are tuned by stretching the fiber cavity.

FFP components are usually made with single-mode fibers but have also been made with different specialty fibers:
·        multi-mode fibers (MMF),
·        polarization-maintaining fibers (PMF),
·        low-polarization sensitivity fibers,
·        dispersion-shifted fibers,
·        D-shaped fibers,
·        highly nonlinear fibers,
·        electro-strictive fibers,
·        fluoride fibers (e.g., ZBLAN).
 
In the blue and violet region, FFP-TFs have been used in a high-resolution inductively coupled plasma atomic emission spectroscopy (ICP-AES) system designed for compact and field-deployable nuclear contamination measurements. In the 600 NM wavelength region, both single-mode FFP-TFs and multi-mode FFP-TFs have been used for proprietary atmospheric monitoring. In the same wavelength region, FFP-SIs have also been used to monitor tunable lasers for uranium enrichment plants. FFP-TFs and FFP-SIs in the 800 and 900 NM regions have been used in laser characterizations and atmospheric Doppler laser radar (Doppler Lidar) measurements. Similarly, devices in the 1.06 µm wavelength ranges have also been useful for various applications including analytical chemistry and spectroscopy. Scientific activities using PM-FFP components included tunable lasers, polarization encoded fiber Bragg grating sensing, as well as fiber-optic spectral polarimeter for biomedical applications

FFP-Is made with different specialty fibers have been investigated for various sensing applications and research activities, including magnetic and electric field sensors, tunable sources for atmospheric sensing, fiber phase modulators, etc. FFP-SIs have proven to be extremely useful in high-resolution laser mode analyses. As they are all-fiber devices, no cumbersome trial-and-error cavity alignments are needed.

As more and more active gain media become available, such as rare-earth doped-fibers and semiconductor active media, FFP components are gaining interests in enabling wavelength tunability and referencing.

Chameleon Thin Film Tunable Filter [CTF]

Based on multi-layer thin-film design and angular tuning, the Chameleon thin-film filters can be incorporated to form tunable sources and tunable detectors for spectrally resolved applications. Intrinsically a free-space optic platform, CTFs can also be employed for free space applications.