General Photonics’ Polarization Scrambler uses a breakthrough all-fibre technology to effectively randomise polarization states. Depolarising by polarization scrambling has many important applications. Scrambling the input polarization can eliminate measurement uncertainties caused by the polarization sensitivity of the testing device. Performance degradation due to polarization dependent gain (PDG) induced in optical amplifiers can also be suppressed by polarization scrambling. In addition, polarization scrambling can be used in systems to facilitate and simplify PMD monitoring. Based on a patented, award-winning all-fibre technology, the PCD-104 delivers superior performance, including extremely low insertion loss, back reflection, and residual phase and amplitude modulation.
Spatial Mode Scrambler
Time varying speckle patterns from a multi-mode fibre can cause problems in many applications that require uniform, stable light distributions at the fibre output. ModeMixer™ is specially designed to solve this problem. Based on General Photonics’ patented fibre squeezer technology, ModeMixer™ effectively randomises multimode speckle patterns over time by modulating multiple sections of a continuous fibre with multiple fibre squeezers. The light distribution at the output appears uniform and stationary when viewed by cameras or detectors with refresh rates lower than ModeMixer™ ’s scrambling rate. In addition, the continuity of the optical fibre minimizes insertion loss. Most importantly, the fibre used for this device undergoes a special surface treatment to prevent breakage under stress, ensuring high device reliability. ModeMixer™ enables applications from DNA sequencing to multimode fibre sensing and test and measurement of multimode fibre devices.
Polarisation Synthesiser / Analyser
PolaFlex™ is a turn-key instrument that can generate and maintain any desired state of polarization (SOP), regardless of the input SOP. It combines General Photonics’ patented polarization controller, in-line polarimeter, and control algorithm into an instrument that functions as both a deterministic polarization state generator and a polarization analyser. The generated SOP and the corresponding Poincaré Sphere can be readily displayed on a computer screen via USB interface. To generate a desired SOP, a user simply inputs the corresponding Stokes parameters using the front panel keypad. The instrument automatically searches for the SOP and maintains it against input SOP fluctuations. Another attractive feature is that the user can scan through 6 distinct SOPs (0°, 90°, ±45°, RHC and LHC) sequentially with user defined speed for Mueller matrix calculations, or select any of the 6 states with the touch of a button. Furthermore, the user can select multiple predetermined SOP traces for the instrument to generate, emulating certain common polarization variations. The instrument can also function as a polarization scrambler, generating random SOP scans with user-defined scanning speed. Finally, with the internal polarization controller disabled, PolaFlex™ can function as an in-line polarimeter, displaying the instantaneous SOP and DOP of the input light beam. This instrument can be quickly and easily calibrated using its built-in self-calibration program to optimise DOP and SOP measurement and control at special wavelengths and temperatures. PolaFlex™ puts all of the tools necessary for polarization management at your fingertips.
Reset Free Polarisation Stabiliser
The PolaStay™ polarization stabilizer actively maintains a stable output state of polarization (SOP) against rapid input SOP fluctuations as fast as 2 ms, and tracks against an endlessly rotating input SOP up to 16p/s without reset. This unique product is a complete system consisting of General Photonics’ polarization controller, in-line polarization monitor, and proprietary algorithm. The instrument's output can be either single mode fibre or PM fibre with the output polarization aligned to its slow axis. When a polariser is placed at the output, the maximum power fluctuation caused by input polarization fluctuation is less than 0.1 dB. This instrument can be used to suppress noise figure in optical amplifiers, reduce PDL effects, demultiplex polarization division multiplexed channels, and eliminate polarization fading in coherent communication and fibre sensor systems. In addition to the standard configuration, specialized versions are available for low power applications (down to -30 dBm) and special wavelengths (1064 nm).
Multifunction Polarisation Controller
Controlling the state of polarization (SOP) of an optical signal has never been easier: This multifunction polarization controller has four operational modes for complete polarization control: variable rate polarization scrambling, manual polarization adjustment, polarization modulation, and externally triggered random SOP generation. Different polarization scrambling modes cause the SOP to a) trace out a spiral pattern about a static or rotating axis with a nearly uniform SOP variation rate for system stress tests (Tornado mode); b) generate a continuous trace with a Rayleigh distribution of SOP variation rate, for emulation of the SOP variation in a fibre link (Rayleigh mode); c) generate a continuous trace with uniform sphere coverage for PDL measurement (Triangle mode); or d) uniformly cover the Poincaré sphere with discrete, random points at a uniform rate (Discrete mode. In the SOP modulation mode, each polarization control axis can be selectively controlled with a sine, square, or triangle wave of user defined frequency and amplitude. Each polarization control axis can also be controlled manually, by setting the input voltage either from the front panel controls or through a remote control interface. In externally triggered scrambling mode, discrete, random SOPs are generated in response to a trigger input, a feature desirable for recirculating loop applications or other applications requiring synchronization with other devices. Finally, the MPC-201 can emulate the Agilent 11896A polarization scrambler function, allowing it to act as a plug-in replacement for this popular device, while offering many more advanced features. PolaMight puts the user in control.
Advanced Multifunction Polarisation Controller
The MPC-202 is an advanced Multifunction Polarization Controller specially designed to meet the requirements of coherent receiver performance tests. It combines General Photonics’ award winning PolaRite™ II/III polarization controller with proprietary polarization control algorithms to achieve a wide range of polarization control functionalities, including high speed quasi-uniform rate polarization scrambling, random-rate polarization scrambling with Rayleigh rate distribution, discrete-state polarization scrambling with high slew rate, sine, square, and triangle-wave SOP modulation, and manual polarization control functions. In particular, the “Tornado” quasi-uniform rate polarization scrambling function can achieve a high SOP scrambling rate of up to 60,000 revolutions/s (more than 360 krad/s) with a narrow rate distribution clustered around the highest rate. In short, the MPC-202 is an ideal tool for production or laboratory testing of polarization related functions and parameters, including passive/active component characterization, performance tests of fibre optic interferometers, sensor systems, RF photonics systems, etc. The quasi-uniform rate high speed scrambling function is particularly useful for SOP tracking speed testing of coherent receivers. The square wave SOP modulation is ideal for SOP recovery time tests.