Research On Optical Filters Based On VIPA (Virtually Imaged Phased Array)

Virtually-imaged phased array (VIPA) is an optical element with a large angular dispersion which has been used as dispersion compensator and optical filter with high resolution. In addition, there are also research in polarization mode dispersion, wavelength division multiplexing and pulse shaping. However, as a result of high standard in incident beams, multiple diffraction orders and large loss, it has not been widely applied.2D spectral imaging can be achieved by using a VIPA in combination with a diffraction grating which is a great improvement in spectral processing. And many novel applications have been presented in fabricate optical filter with high resolution and high signal noise ratio, making complicate2D spectral processing and2D spectral imaging.Beginning with the VIPA basic working principle, this paper describes in detail the VIPA dispersion law based on paraxial wave theory, simulating the wavelength-light power strength two-dimensional mapping relationship of the beam, and in contrast with plane wave theory on the performance parameters of the simulation analysis; At the same time, comprehensively and systematically studies application in DWDM, and using approximate simulation discusses spatial chirp effect on peak wavelength shift and line width of the spectrum for eight channel hyperfine wavelength division multiplexing system, where using mask barrier method to simulate fiber array in the approximate simulation model. In addition, this paper builds a simulation model of DWDM system by means of spatial gate, working on its main performance parameters for parameter optimization analysis in combination with fiber size and the effect of incident angle on performance. This filter is different from the DWDM apparatus that using a small hole above the2D output plane as a space filter, while directly using a piece of optical fiber receiving after the output beam in DWDM.As a result of the limitation of the time and experimental condition, performance and reliability of simulation model of this DWDM system still needs to be demonstrated in experiment. Application value and prospect of eight channel system and filters by means of spatial gate remains to be further discussed.