Test & Measurements
 
Wavelength Stabilizer: Thermally stabilized FFPIs can be employed in a frequency control feedback loop to stabilize laser sources within the wavelength range of 400nm to 1650nm.
 
Beat Frequency Noise Source: A useful and unique high frequency measurement technique has been developed that uses a dense comb source generated from the combination of a broadband source and a FFPI. This technique provides a significant increase in measurement dynamic range for high-frequency characterization of photoreceivers.[1]
 
Stabilization in Amplified Delayed Self-Heterodyne Interferometer: Very high resolution linewidth measurement has been demonstrated by using an amplified re-circulating delayed self-heterodyne interferometer. A FFP-TF is incorporated to lock on the input signal and prevent spurious lasing. [2]
 
Tunable and Swept-Wavelength Source: Swept-wavelength and tunable lasers across different spectral regions can be built by incorporating a FFP-TF or a CTF into an active cavity. Different wavelength ranges can be obtained by using different active media such as active fibers, waveguides, and semiconductor optical amplifiers. Because of the high profile purity and low-loss nature of Micron Optics tunable filters, the resulting swept lasers can exhibit very high signal to spontaneous emission ratio (SSE) and signal to total spontaneous emission ratio (STSE) over a wide tuning range. An incoherent, narrowband swept source can also be configured by using a broadband source as the input.
 
A wide range of applications can take advantage of swept-wavelength lasers. These include WDM component testing (in 1.5µm for general network components, in 1.4 µm for Raman amplifier components, in 0.98µm for pump stabilizing FBGs), remote sensing, mechanical sensing, ranging, and bio-medical diagnostics. [3-18]
 
Tunable, Short-Pulse, Mode-Locked Lasers: High quality and high repetition-rate short-pulse lasers can be promising light sources for optical communication applications as well as numerous scientific and engineering applications. FFP-TFs and FFP-Is have been employed in a variety of short-pulse laser configurations to perform crucial functions such as the stabilization of mode-locked pulses, regenerative and harmonic mode locking, and wavelength tuning. Furthermore, FFP-TFs made of polarization-maintaining fibers have also been incorporated into mode-locked fiber lasers for transmitter applications.
 
When a section of active fiber (erbium/ytterbium co-doped fiber) is incorporated to form a FFP laser (FFPL), it can function as a multimode source and a high-finesse filter within a ring configuration to generate robust and stable mode-locked pulses. Enabled by precise fabrication processes, FFP-Is and FFP-Ls can contribute to the realization of practical and compact short pulse sources with precise repetition rates. [19-26]
 
Signal Generation By Modulation Side-Band Filtering: High-repetition-rate (10 to >100GHz) soliton pulse sources are very useful in high data-rate optical communications. One rather efficient and cost effective technique has been demonstrated that uses a single DFB laser source, an external phase modulator, and a FFP-TF. Specifically, the DFB laser was phase modulated at a specific frequency, and two optical carriers were generated by using a FFP-TF to filter out a pair of harmonic sidebands. The beat signal from the two combined side-band carriers were then amplified and compressed using a dispersion-shifted fiber to produce near-transform-limited soliton pulse train. A 100GHz soliton pulse train was demonstrated to have with very low timing jitter due to the advantage that the two sidebands share a common frequency noise. [27]

 
Microwave Photonics
 
Scanning Receiver for Microwave Signal Processing: High-resolution FFP-TFs, designed to have FSR in the microwave frequency ranges of 10’s of GHz, and bandwidths of MHz, have been applied in microwave scanning receiver applications. In essence, the FFP-TF can be used to analyze microwave sidebands that have been imposed on an optical carrier by a radio frequency (RF) signal. This approach should facilitate the removal of bulky local oscillator and downconverter blocks from the receiver system. [28]
 
Spectroscopy

Tunable filters can be fabricated for spectroscopic applications in various spectral regions, from 400nm violet to 1.6µm IR. Application techniques may include spectral noise filtering and signal band selection, source stabilization and referencing, emission band detection and analysis. Application areas include atomic emission spectroscopy, analytical chemistry, and remote atmospheric monitoring. [29]
 
Aerospace & Lidar
 
Micron Optics FFP-TFs have been designed into satellite communication platforms and structure health monitoring of aerospace vehicles. The filters robust design has allowed full qualification in rocket launch tests. Tunable filters and associated modules and instruments can be applied for:

• Ranging
• Atmospheric sensing
• Free-space communication
• In-flight optical networks
• In-flight structure health monitoring and control
   

Bio-Medical

Micron Optics tunable sources, filters, and spectrum analyzers can be applied in bio-medical field to analyze fluorescence spectrum, spectrally-resolved light stimulation, optical coherence tomography, fiber-optic spectral polarimeter, and other critical optical parameters.[30]
 
Defense and Security

In security applications such as perimeter surveillance, fault detection, and ranging, fiber-optic sensing technologies are being actively adopted. In sensing techniques incorporating optical frequency domain reflectometry (OFDR) or fiber Bragg grating (FBG) sensors, Micron Optics swept and tunable lasers can be applied as sensor interrogation sources.
 
Micron Optics’ swept sources and OSA instruments can be applied for bio-medical and chemical sensing of trace pollutants, toxic gases, and in vivo temperature profiling in human bodies. It will be extremely useful to advance the optical monitoring systems to protect trans-continental oil/gas pipelines, bridges/tunnels, and biological contamination.
 
FFP-Is made with different specialty fibers have been investigated for various sensing applications and research activities; some examples include magnetic and electric field sensors. [31]