An ultra-narrow-band comb filter

Abstract

The invention relates to an ultra-narrow band comb type filter, which belongs to a photoelectronic device and solves the problems that the existing comb type filter does not have the polarization beam splitting function, and the single channel has wide band width. The ultra-narrow band comb type filter consists of a photoisolator, a polarization beam splitter, a first multi-channel filter and a second multi-channel filter, wherein an incident light beam enters the polarization beam splitter through the photoisolator and is divided into a path of S light and a path of P light, the S light and the P light respectively enter the first multi-channel filter and the second multi-channel filter to be filtered, the center frequencies of the first multi-channel filter and the second multi-channel filter are staggered and conform to the international telecommunication union regulations, the output channel intervals are respectively 50GHz, 100GHz or 200GHz, and the output of the first multi-channel filter and the output of the second multi-channel filter are the output of the ultra-narrow band comb type filter. The ultra-narrow band comb type filter simultaneously has the polarization beam splitting function of the polarization beam splitter and the ultra-narrow band multi-channel filtering function of the multi-channel filters, adopted optical devices are few, the structure is simple, the output signal line width is narrow, the output channel intervals can select 50GHz, 100GHz or 200GHz, the center frequency conforms to the international telecommunication union regulations, and the ultra-narrow band comb type filter is suitable for being used in dense wave multiplexer systems with different requirements.

Description

technical field [0001] The invention belongs to optoelectronic devices, in particular to an ultra-narrow-band comb filter. Background technique [0002] With the development of dense wavelength division multiplexing (DWDM) systems, in order to better utilize bandwidth resources, channel spacing becomes narrower and narrower. The DWDM system with 100 GHz spacing of 32 waves or 40 waves has been widely used commercially. In order to further improve bandwidth utilization, channel spacing has been developed from 100 GHz to 50 GHz or even narrower. The narrower the channel spacing, the higher the requirements for the DWDM system multiplexer and demultiplexer, and the greater the difficulty of the manufacturing process. The 50 GHz and narrower bandpass filters used as demultiplexers have low yields, which makes narrowband filters expensive. The application of the comb filter will greatly reduce the cost of the system and relieve the pressure of the DWDM system on the filter dev...

AI Technical Summary

Problems solved by technology

[0004] The invention provides an ultra-narrow-band comb filter, which solves the problem that the existing comb filter does not have the function of polarization splitting and has a wide single-channel bandwidth

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