Wavelength division multiplexing module with ultrahigh isolation
By using a combination of dual-fiber collimators and single-fiber collimators in the wavelength division multiplexer, along with a dual-filter and fusion protection tube structure, the problem of insufficient isolation in the prior art is solved, and the miniaturization and cost-effectiveness of the ultra-high isolation wavelength division multiplexing module are achieved.
Patent Information
- Application Number
- CN202423279138.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-12-30
AI Technical Summary
Existing commercially available filter-type wavelength division multiplexing devices have low transmission and reflection isolation, making it difficult to meet the ultra-high isolation requirements of 60dB and above. Furthermore, the multi-stage cascaded structure results in high cost, large size, and unsuitability for miniaturized applications.
A combination of dual-fiber collimators and single-fiber collimators is used. The light of the target transmission wavelength is transmitted into the single-fiber collimator by using dual filters. Multiple wavelength division multiplexers are connected in series, and each wavelength division multiplexer is equipped with dual filters to improve the isolation between the transmission and reflection ends, meeting the isolation requirement of 60dB and above. Miniaturized packaging is achieved through fusion-bonded protective tubes and adhesive bonding sealing structure.
It achieves ultra-high isolation between the transmission and reflection ends, reduces the number of components, lowers costs, and meets the requirements of small-size packaging, making it suitable for miniaturized applications.
Smart Images
Figure CN223565934U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to communication field especially a kind of super-high isolation wave division multiplexing module. BACKGROUND
[0002] Wave division multiplexing (WDM) is the main means of current fiber communication to increase capacity, filter piece wave division multiplexer (FWDM) belongs to WDM one, it is based on thin-film filter technology, can be combined or separated in the wide wavelength range with different wavelength light.FWDM has the characteristics such as low loss, high isolation and high reliability, is widely used in WDM fiber system, CATV system and FTTH system etc.
[0003] The transmission isolation and reflection isolation of the FWDM device that can be commercialized in the current market are generally low, the transmission isolation is only 30dB, the reflection isolation is only 15dB, if the reflection isolation is increased to 30dB, it causes high cost.In some special application fields, super-high isolation FWDM module is used, such as isolation requirement 60dB or above, for this application, in order to improve transmission and reflection isolation, and under the premise of using commercial cost filter piece, the conventional structure such as Figure 1 , multiple devices are used in cascade, such as FWDM device 10, 20 and 30 with the same transmission and reflection wavelength, the transmission end fiber 002 of device 10 and the COM end fiber 004 of device 20 are fused by fusion protection tube 003, the reflection end fiber 006 of device 10 and the COM end fiber 008 of device 30 are fused by fusion protection tube 007, the isolation of the last stage transmission end 005 and reflection end 009 is improved by multi-stage transmission mode.This scheme uses more FWDM devices in series, the reflection isolation may still not reach 60dB, and the insertion loss after multi-stage transmission increases, reduces the system margin, at the same time, causes the cost waste of multiple devices, the manufacturing volume is also relatively large, and there is incompatibility for some miniaturization application scenarios. UTILITY MODEL CONTENT
[0004] In view of the above problems, the utility model provides a kind of super-high isolation wave division multiplexing module, and double-fiber collimator is transmitted to single-fiber collimator by double filter piece with target transmission wavelength light, can meet the 60dB and above super-high isolation index requirement of transmission end and reflection end, reduce volume, meet small size package.
[0005] The technical scheme adopted by the utility model is:
[0006] The utility model provides a kind of super-high isolation wave division multiplexing module, including at least two wave division multiplexers, each wave division multiplexer has reflection end, incident end and transmission end, and incident end and transmission end are respectively at both sides of wave division multiplexer, and reflection end is with incident end at the same side of wave division multiplexer, it is characterized by: each wave division multiplexer is connected in series in turn, and the reflection end of one wave division multiplexer in adjacent two wave division multiplexers is connected with the incident end of another wave division multiplexer, and each wave division multiplexer includes double-fiber collimator and single-fiber collimator respectively placed into the both ends of first housing tube, and double-fiber collimator is coupled with single-fiber collimator, and the end of double-fiber collimator close to single-fiber collimator is equipped with double filter for transmitting target transmission wavelength light into single-fiber collimator, and double filter includes two single filters that are attached.
[0007] Preferably, the transmission isolation of the single filter in the double filter is greater than 35dB.
[0008] Preferably, the reflection end fiber of one wave division multiplexer in the adjacent two wave division multiplexers is fused with the incident end fiber of another wave division multiplexer through a fusion protection tube.
[0009] Preferably, the double-fiber collimator and the single-fiber collimator in the wave division multiplexer are respectively sleeved into the housing tube, and are sealed by point gluing and UV curing.
[0010] More preferably, the housing tube is a glass tube.
[0011] Preferably, the wave division multiplexing module includes two wave division multiplexers connected in series.
[0012] Preferably, the wave division multiplexing module includes three wave division multiplexers connected in series.
[0013] Preferably, each wave division multiplexer is packaged in a box body.
[0014] Compared with the prior art, the utility model has the beneficial effects that: the utility model provides a kind of super-high isolation wave division multiplexing module, and double filter is arranged at the end of double-fiber collimator of each wave division multiplexer connected in series, to transmit target transmission wavelength light into single-fiber collimator, and the transmission isolation of the single filter in the double filter is greater than 35dB, so as to meet the super-high isolation index requirement of 60dB or more of the transmission end and the reflection end of wave division multiplexer target wavelength, compared with the same index product of multi-stage interconnection structure, the number of cascaded devices can be reduced, the cost is reduced, and small size packaging is met. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 It is a schematic diagram of the principle of conventional high-isolation filter type wave division multiplexer module.
[0016] Figure 2The utility model provides a kind of WDM module of super-high isolation degree first kind of implementation mode's schematic view.
[0017] Figure 3 The utility model provides a kind of WDM module of super-high isolation degree first kind of implementation mode encapsulation in the schematic view of box body.
[0018] Figure 4 The utility model provides a kind of WDM module of super-high isolation degree first kind of implementation mode encapsulation in the right view of box body.
[0019] Figure 5 The utility model provides a kind of WDM module of super-high isolation degree second kind of implementation mode's schematic view.
[0020] Figure 6 The utility model provides a kind of WDM module of super-high isolation degree first kind of implementation mode encapsulation in the schematic view of box body.
[0021] Figure 7 The utility model provides a kind of WDM module of super-high isolation degree second kind of implementation mode encapsulation in the right view of box body.
[0022] Figure 8 The utility model provides a kind of WDM module of super-high isolation degree in the schematic view of wave division multiplexer.
[0023] Figure 9 The utility model provides a kind of WDM module of super-high isolation degree in the schematic view of double-fiber collimator. Specific embodiments
[0024] According to the preferred embodiment of the utility model provided by the drawings is specifically explained.
[0025] Figures 2 to 9 The utility model provides a kind of WDM module of super-high isolation degree preferred implementation mode. As Figures 2 to 9As shown, the ultra-high isolation wavelength division multiplexing module includes at least two wavelength division multiplexers 10, each wavelength division multiplexer 10 has a reflection end 101, an incident end 102 and a transmission end 103, the incident end 102 and the transmission end 103 are respectively at both sides of the wavelength division multiplexer, the reflection end 101 is at the same side of the incident end 102 of the wavelength division multiplexer, the wavelength division multiplexers 10 are sequentially connected in series, the reflection end 101 of one of the two adjacent wavelength division multiplexers 10 is connected with the incident end 102 of the other wavelength division multiplexer, each wavelength division multiplexer 10 includes a double-fiber collimator 11 and a single-fiber collimator 12 which are respectively arranged at both ends of the holding tube 13, the double-fiber collimator 11 is coupled with the single-fiber collimator 12, the double-fiber collimator 11 is provided with a double filter 111 for transmitting light of a target transmission wavelength into the single-fiber collimator at the end close to the single-fiber collimator 12, the double filter 111 includes two single filters which are attached together; in this way, the full-band 1260-1650nm optical signal is input from the incident end 102 fiber of the wavelength division multiplexer 10 at the first position, the light of the target transmission wavelength is transmitted into the corresponding single-fiber collimator 12 through the first double filter 111 of the target transmission wavelength, that is, the light is output from the transmission end 103 fiber of the wavelength division multiplexer 10 at the first position; while the other reflected light signal enters the incident end 102 fiber of the adjacent wavelength division multiplexer 10 from the reflection end 101 fiber of the wavelength division multiplexer 10 at the first position, the light of the target transmission wavelength is transmitted into the corresponding single-fiber collimator 12 through the double filter 111 of the target transmission wavelength, that is, the light is output from the transmission end 103 fiber of the wavelength division multiplexer 10, the transmission of the other wavelength division multiplexers is similar; so as to meet the requirement of the wavelength division multiplexer target wavelength transmission end and reflection end 60dB and above ultra-high isolation degree index, compared with the same index product of the multi-stage interconnection structure, the number of cascaded devices can be reduced, the cost is reduced, and the small size package is met.
[0026] As shown in Figure 9 , the transmission isolation of the single filter in the double filter 111 is greater than 35dB; the transmission isolation of the single filter in the double filter 111 used in the wavelength division multiplexer 10 at the first position is greater than 35dB, so that the transmission isolation detected by the transmission end 103 fiber after the transmission light passes through the double filter 111 can reach 60dB and above; the transmission isolation of the single filter in the double filter 111 used in the wavelength division multiplexer 10 at the rear position is greater than 35dB, and the reflection isolation of the wavelength division multiplexer 10 at the front position is superimposed, so that the transmission isolation detected by the transmission end 103 fiber after the transmission light passes through the double filter 111 can reach 60dB and above.
[0027] As shown in Figure 2 and Figure 5 , the reflection end fiber of one of the two adjacent wavelength division multiplexers is fused with the incident end fiber of the other wavelength division multiplexer by a fusion protection tube 20.
[0028] As shown in Figure 8 The dual-fiber collimator 11 and the single-fiber collimator 12 in the wavelength division multiplexer 10 are respectively sleeved into the accommodating tube 13, and are sealed by point gluing and UV curing; in assembly, the dual-fiber collimator 11 and the single-fiber collimator 12 are coupled, after meeting the parameter standards, the dual-fiber collimator 11 and the single-fiber collimator 12 are respectively sleeved into the accommodating tube 13, and are sealed by point gluing and UV curing, thereby the wavelength division multiplexer 10 is completed.
[0029] The wavelength division multiplexer 10 is packaged in the box body 30. The box body 30 is a small-size aluminum box. The optical fibers connected with the ends of the wavelength division multiplexer 10 can be common bending radius optical fibers or bending-resistant optical fibers such as G657A2 / B3. According to the type of the bending-resistant optical fiber, the box body 30 can be made smaller in size.
[0030] Figure 2 The wavelength division multiplexer module provided by the utility model has the advantages that the wavelength division multiplexer module includes two wavelength division multiplexers, the reflection end 101 of the first wavelength division multiplexer is connected with the incidence end 102 of the second wavelength division multiplexer through an optical fiber, the full-waveband 1260~1650nm optical signal is input from the incidence end 102 of the first wavelength division multiplexer 10 through the optical fiber, the target transmission wavelength light is transmitted to the first single-fiber collimator 12 through the first double filter 111 of the target transmission wavelength, that is, the target transmission wavelength light is output from the transmission end 103 of the first wavelength division multiplexer 10 through the optical fiber, the transmission isolation degree of the single filter in the double filter 111 used in the first wavelength division multiplexer 10 is greater than 35dB, so that the transmission isolation degree detected by the transmission end 103 optical fiber after the transmission light passes through the double filter 111 can reach 60dB or above, and the other reflected optical signals enter the incidence end 102 of the second wavelength division multiplexer through the reflection end 101 of the first wavelength division multiplexer 10, the target transmission wavelength light is transmitted to the single-fiber collimator 12 through the double filter 111 of the target transmission wavelength, that is, the target transmission wavelength light is output from the transmission end 103 of the second wavelength division multiplexer through the optical fiber, the transmission isolation degree of the single filter in the double filter 111 used in the second wavelength division multiplexer 10 is greater than 35dB, and the reflection isolation degree of the first wavelength division multiplexer 10 is superimposed, so that the transmission isolation degree detected by the transmission end 103 optical fiber after the transmission light passes through the double filter 111 can reach 60dB or above, thereby meeting the requirement of the 60dB or above super-high isolation degree of the target wavelength transmission end and reflection end of the wavelength division multiplexer. Figures 3 to 4 As shown in
[0031] Figure 5The utility model provides a kind of WDM module of super-high isolation degree second embodiment provided in the utility model, in this embodiment, three WDMs are included in WDM module, three WDMs are respectively first WDM, second WDM and third WDM, the reflection end 101 of first WDM is connected with the incidence end 102 of second WDM by optical fiber, the reflection end 101 of second WDM is connected with the incidence end 102 of third WDM by optical fiber, and the optical signal of full wave band 1260~1650nm (wherein 1625~1650nm can be used for OTDR monitoring) is input from the optical fiber of the incidence end 102 of first WDM, and the light of target transmission wavelength is transmitted to single-fiber collimator 12 by target transmission wavelength double filter piece 111, that is, the optical fiber output of transmission end 103 of first WDM, the transmission isolation of the optical fiber detection of transmission end 103 can reach 60dB and above after transmission light passes through double filter piece 111, and other reflected optical signals enter the optical fiber of the incidence end 102 of second WDM by the optical fiber of the reflection end 101 of first WDM, and the light of target transmission wavelength is transmitted to single-fiber collimator 12 by target transmission wavelength double filter piece 111, that is, the optical fiber output of transmission end 103 of second WDM, the transmission isolation of the optical fiber detection of transmission end 103 of second WDM can reach 60dB and above after transmission light passes through double filter piece 111 of second WDM, and the light of third WDM is output by the optical fiber of transmission end 103 of third WDM, the transmission isolation of the optical fiber detection of transmission end 103 of third WDM can reach 60dB and above after transmission light passes through double filter piece 111 of third WDM, and the transmission isolation of the optical fiber detection of transmission end 103 of third WDM can reach 60dB and above after transmission light passes through double filter piece 111 of third WDM. Figures 6 to 7 As shown in FIG.
[0032] In summary, the technical scheme of the utility model can fully and effectively realize the above-mentioned utility model purposes, the structure and function principle of the utility model have been fully verified in the embodiments, the expected effects and purposes can be achieved, various changes or modifications can be made to the embodiments of the utility model without departing from the principles and essence of the utility model. Therefore, the utility model includes all the replacements within the range mentioned in the patent application, any equivalent changes made within the range of the patent application of the utility model belong to the patent application of the utility model.
Claims
1. A super-high-isolation WDM module, comprising at least two WDMs, each WDM having a reflection end, an incident end and a transmission end, the incident end and the transmission end being on opposite sides of the WDM, the reflection end being on the same side of the WDM as the incident end, characterized in that: The wavelength division multiplexers are connected in series, the reflection end of one of the two adjacent wavelength division multiplexers is connected with the incidence end of the other wavelength division multiplexer, each wavelength division multiplexer comprises a double-fiber collimator and a single-fiber collimator respectively arranged at two ends of a first placement tube, the double-fiber collimator is coupled with the single-fiber collimator, and the end of the double-fiber collimator close to the single-fiber collimator is provided with a double filter for transmitting light of a target transmission wavelength into the single-fiber collimator, the double filter comprises two single filters which are attached to each other.
2. The ultra-high isolation wavelength division multiplexing module of claim 1, wherein: The transmission isolation of the single filter in the double filter is greater than 35 dB.
3. The ultra-high isolation WDM module of claim 1, wherein: The reflection end fiber of one of the two adjacent wavelength division multiplexers is fused with the incidence end fiber of the other wavelength division multiplexer through a fusion protection tube.
4. The ultra-high isolation WDM module of claim 1, wherein: The double-fiber collimator and the single-fiber collimator in the wavelength division multiplexer are respectively sleeved into the placement tube, and are sealed by point gluing and UV curing.
5. The ultra-high isolation WDM module of claim 4, wherein: The placement tube is a glass tube.
6. The ultra-high isolation WDM module of claim 1, wherein: The wavelength division multiplexing module comprises two wavelength division multiplexers connected in series.
7. The ultra-high isolation WDM module of claim 1, wherein: The wavelength division multiplexing module comprises three wavelength division multiplexers connected in series.
8. The ultra-high isolation WDM module of claim 1, wherein: Each wavelength division multiplexer is packaged in a box body.