The BWN-FPC manual fiber polarization controller adjusts the state of polarization (SOP) in application-matched single-mode fiber. It is available with two or three paddles and 18, 27 or 56 mm loops. A usable quotation must state the wavelength, exact fiber, winding, lead lengths and termination.
Primary action: Request a configuration review.
Secondary action: Request the BWN-FPC RFQ checklist.
Product value summary
BWN-FPC is intended for setups where an operator can turn the paddles while watching a polarization-sensitive optical response. It is a manual controller, not an active tracker or a closed-loop stabilization system.
Loop diameter is not a performance grade. It changes curvature, retardance, fiber length and controller size. Approve the exact fiber, operating wavelength, loop diameter and winding pattern as one build.
BWN-FPC configuration-first rule: Do not approve loop diameter by itself. Freeze the fiber, wavelength, paddle and loop geometry, winding, leads and interface, and acceptance evidence in the same configuration record.
Use the platform specifications below for initial screening. The quotation must identify the supplied build and its acceptance conditions.
Related passive components are listed under Fiber Optic Components.
Quick navigation
- Choose a loop diameter
- Review published specifications
- Check fiber and interface compatibility
- Compare quotations on one baseline
- Define testing and acceptance
- Prepare a complete RFQ
Main features
- Manual paddle-style polarization adjustment in single-mode fiber
- Two- or three-paddle configurations
- Published loop options of 18 mm, 27 mm and 56 mm
- Empty or preloaded configurations, with unterminated, FC/PC or FC/APC options
- Standard 0.9 mm tube; 3 mm jacketed option subject to geometry review
- Fiber length of 0.25 m or customized for the winding and leads
- Aluminum base and Delrin paddles
- Quotation review based on wavelength, fiber, winding and termination
How does a paddle fiber polarization controller work?
Fiber wound around a paddle develops bend-induced birefringence. Rotating the paddle changes the orientation of the induced axes relative to the transmitted polarization. Retardance depends on the fiber properties, including cladding geometry and bend response, as well as wavelength, loop diameter and number of turns. The operator adjusts the paddles while observing the optical output.
A three-paddle arrangement approximates a quarter-wave, half-wave and quarter-wave sequence at its design condition. Its response still depends on the loaded fiber, wavelength, loop diameter and turns. During use, turn the paddles while monitoring the relevant optical response; record the loaded configuration and measured condition if the setup must be reproduced.
What changes when loop diameter changes?
Loop diameter affects four coupled design variables:
| Variable | Smaller loop | Larger loop | What must be verified |
|---|---|---|---|
| Curvature | Tighter bend | Lower curvature | Fiber and wavelength bend sensitivity |
| Retardance | Changes with the stronger bend and loaded length | Changes with the lower curvature and loaded length | Required winding at the design wavelength |
| Fiber used per turn | Less | More | Total loaded length plus lead allowance |
| Mechanical envelope | More compact | Longer/wider controller envelope | Mounting, connector clearance and paddle sweep |
Changing the diameter changes the loaded geometry. Recheck the fiber, wavelength and turns rather than treating the new loop as a drop-in size change.
The published loop diameter describes the controller geometry. It is not a generic minimum bend-radius rating for the loaded fiber. Review bend loss for the exact fiber and wavelength.
Which polarization controller loop diameter should you choose?
Quick answer: Start with the paddle layout, then check the loop curvature against the exact fiber and operating wavelength. BWN-FPC publishes an 18 mm loop for two paddles and 27 or 56 mm loops for three paddles. A 56 mm loop lowers curvature, but it does not guarantee lower total insertion loss.
| Starting option | Paddles | When to consider it | Check before approval |
|---|---|---|---|
| 18 mm loop | 2 | The setup needs the compact published two-paddle layout | Verify bend sensitivity for the selected fiber and wavelength |
| 27 mm loop | 3 | The setup needs a compact three-paddle layout | Define the winding for this diameter |
| 56 mm loop | 3 | The fiber configuration needs lower curvature | Verify fiber length, available space and measured loss |
Five-step manual polarization controller selection method
1. Define the optical task
State the input condition, desired output state, wavelength or band, source type and measurement method. If the system needs continuous compensation, select an active controller instead.
2. Confirm the exact fiber
Provide the fiber designation, single-mode operating condition, cladding or cover construction and connectorized or bare-fiber requirement. Wavelength alone is not enough to select the loop.
3. Determine the required winding
Map the proposed fiber, wavelength and diameter to a stated number of turns on each paddle. For an empty controller, use an approved loading instruction rather than copying a winding from a photograph or another controller.
4. Review optical and mechanical risk
Review bend-loss evidence, the insertion-loss measurement boundary, clamp compatibility, fiber routing, mounting points and the full paddle sweep. A controller can fit when the paddles are parked and still hit nearby hardware during adjustment.
5. Approve one configuration record
Record the model, paddle count, loop diameter, exact fiber, winding, total fiber length, lead lengths, termination, wavelength and agreed acceptance evidence.
An RFQ that states only "1550 nm, three paddles, FC/APC" is incomplete. It still needs the fiber designation, loop diameter, winding, lead lengths, quantity and acceptance requirements.
Need a winding review? Send the application, monitored optical response, wavelength, exact fiber and preferred controller envelope, and mark the winding as review requested. Do not copy turns from another diameter or supplier photograph.
How much fiber does a polarization controller need?
For an initial geometry check, the fiber used by the loops can be estimated as:
looped fiber length ≈ π × loop diameter × total number of turns
Use consistent units. Then add the internal routing length, input lead, output lead and a handling allowance defined by the loading method. This is a planning calculation, not a substitute for the approved loading drawing.
Do not confuse these three quantities:
- Looped length: fiber wrapped around the paddles
- Internal routing length: fiber between paddles and clamps
- External lead length: usable fiber outside the controller body
The order should state all three or reference a drawing that defines them.
Published BWN-FPC technical specifications
The table separates published family data from details that still need configuration-level approval.
| Parameter | Published BWN-FPC information | Procurement status |
|---|---|---|
| Model | BWN-FPC | Verified on current BWNFiber product page |
| Controller type | Manual paddle-style fiber polarization controller using stress-induced birefringence | Verified on current BWNFiber product page |
| Number of paddles | 2 or 3 | Verified |
| Loop diameter | 18 mm for 2 paddles; 27 mm or 56 mm for 3 paddles | Verified |
| Operating wavelength | 480 to 2400 nm published platform range | Map the quoted wavelength to the selected fiber and winding; the range does not describe one universal build |
| Fiber type | Application-matched single-mode fiber | Exact designation required for quotation |
| Fiber cover | 0.9 mm tube standard; 3 mm jacketed option stated as available | Confirm against the selected geometry |
| Fiber length | 0.25 m or customized | Confirm total loaded length and both leads |
| Connector options | None, FC/PC or FC/APC | Confirm mating interface and key requirement |
| Published preloaded connector detail | 2.0 mm narrow key | Confirm for the selected termination |
| Insertion loss including connectors | 0.2 dB typical | Define the maximum limit, wavelength, reference plane and test method |
| Return loss | 55 dB with FC/APC connectors | Define the measurement conditions and acceptance limit |
| Optical power handling | 0.5 W | Review the source conditions and final configuration before use |
| Materials | Aluminum base; Delrin paddles | Verified |
| Operating/storage temperature | Not published | Required before publication or purchase if material to the application |
| Dimensions, weight and mounting drawing | Not published | Request a configuration drawing |
| Certification and named test standard | Not published | Add only with approved evidence |
| MOQ, lead time and packaging | Not published | Confirm in the quotation |
Ordering note: The typical 0.2 dB figure is not a lot-acceptance limit. Put the wavelength, fiber, connectors, reference plane, test method and pass/fail threshold in the approved quotation or configuration-specific specification.
Specification notice: Published family values are for reference only and are not a guarantee for every fiber, winding or termination. The approved quotation governs the supplied build.
Need configuration-specific evidence? Request a datasheet and dimension/loading drawing for the proposed build. Use the family table for screening, but use approved configuration documents for technical acceptance.
Fiber, interfaces and compatibility
Compatibility depends on the loaded build, not a brand list.
Define the loaded fiber and termination
BWN-FPC is described for application-matched single-mode fiber. The public page lists a 0.9 mm tube as standard and a 3 mm jacketed option that needs review for the selected geometry. The controller can be ordered without connectors or with FC/PC or FC/APC terminations. State the exact fiber, cover, mating interface, key requirement and both lead lengths.
Empty versus preloaded controller
- Choose an empty controller when the user will load a qualified fiber and can follow an approved winding instruction.
- Choose a preloaded controller when the fiber, winding, leads and termination should arrive as one defined assembly.
Performance stated for a preloaded assembly does not automatically apply to an empty body loaded by the user.
Applications
BWN-FPC fits systems where an operator can adjust the paddles while observing a polarization-sensitive response.
- Fiber component testing
- Polarization-dependent loss measurement setups
- Fiber-laser and amplifier experiments
- Fiber sensing and interferometric experiments
- Laboratory optical communication setups
- Optical research and teaching setups
Match the application to an observable response
The controller changes polarization; it does not measure the result. Define what the operator will watch before selecting the controller or writing an acceptance plan.
| Optical task | Response to monitor | Configuration check | Manual-control boundary |
|---|---|---|---|
| Align to a polarization-sensitive component | The component-specific transmitted power or response | Wavelength, exact fiber, connector path and target device interface | Suitable when an operator can adjust and verify a static operating point |
| Build a PDL measurement setup | The power change produced as the input SOP is varied | Measurement method, required SOP coverage, reference plane and detector setup | BWN-FPC can provide manual adjustment; it is not a PDL meter or an automated scrambler |
| Optimize an interferometric or sensing experiment | Fringe visibility or the defined sensor response | Fiber path, environmental stability and required readjustment interval | Manual adjustment does not compensate continuous temperature or stress drift |
| Tune a fiber-laser or amplifier experiment | The experiment-specific optical response | Source wavelength, power condition, exact fiber and winding | Review the source condition before use; no active lock is published |
| Demonstrate polarization transformation in a laboratory | The measured output SOP or polarization-sensitive response | Required measurement instrument and repeatability record | Appropriate for hands-on adjustment, not unattended stabilization |
If the output must remain at a target SOP while the input or environment changes, define the required response speed and choose an active control system instead of treating a manual paddle controller as a stabilizer.
Need an application-fit review? Send the optical task, response to be monitored, wavelength, exact fiber and expected adjustment mode so BWNFiber can address the proposed manual-control configuration in the quotation. If continuous control is required, do not request BWN-FPC as a substitute for an active system.
How to build the model/configuration code for quotation
The public page identifies the family as BWN-FPC but does not list option-specific model codes. For a custom manual fiber polarization controller, use this RFQ string until BWNFiber publishes an approved coding table:
BWN-FPC / wavelength / exact fiber / 2 or 3 paddles / loop diameter / turns per paddle / input lead / output lead / connector / quantity / acceptance documents
Do not turn an example configuration string into an official model number without BWNFiber approval.
How to compare manual polarization controller quotations
Normalize every quotation to the same technical baseline. A lower price is not comparable if the fiber, winding, lead length, test boundary or included documents are different.
| Comparison field | What the quotation should state | Why it prevents a false comparison |
|---|---|---|
| Controller role | Manual paddle, active controller, squeezer or another mechanism | Separates products that perform different control tasks |
| Supplied condition | Empty body or preloaded assembly | Prevents assembly performance from being assigned to a user-loaded body |
| Optical configuration | Design wavelength or band, exact fiber designation and cover construction | Exposes configurations that only share a nominal wavelength |
| Paddle and winding geometry | Paddle count, loop diameter and turns on each paddle | Keeps retardance-related geometry visible instead of hiding it behind a family name |
| Fiber-length definition | Looped length, internal routing length and usable input/output leads | Prevents a total-length value from being mistaken for usable lead length |
| Termination | No connector, FC/PC or FC/APC, plus mating interface and key requirement | Makes connectorized builds mechanically and optically comparable |
| Optical values | Typical or maximum value, test wavelength, DUT boundary, reference plane and method | Prevents a catalog typical value from being compared with an agreed acceptance limit |
| Mechanical evidence | Overall envelope, mounting points, lead orientation and full paddle sweep | Identifies fit and access conflicts before installation |
| Included technical records | Configuration datasheet, drawing, loading instruction and available test record | Shows what evidence will govern inspection and repeat orders |
| Commercial basis | Prototype and production quantity, price, MOQ, lead time, packaging and quote validity | Keeps commercial differences separate from technical differences |
Create one comparison row per proposed build. If a field is unknown, mark it to be confirmed rather than assuming that two catalog families are equivalent.
BWN-FPC versus adjacent polarization solutions
| Solution type | Use when | Boundary |
|---|---|---|
| BWN-FPC manual paddle controller | An operator can adjust the state while watching the optical response | No published continuous feedback, remote control or locking function |
| Active or motorized controller | The system needs automated scanning, remote adjustment or closed-loop compensation | These functions are not published for BWN-FPC |
| Polarization-maintaining fiber assembly | The system must preserve a defined axis after an aligned launch | A PMF assembly does not replace arbitrary state transformation |
Common specification mistakes to correct before ordering
| Incomplete or unsafe shortcut | Procurement risk | Corrective check |
|---|---|---|
| “1550 nm polarization controller” with no fiber designation | Wavelength alone does not define bend response or winding | Record the exact fiber, cover, wavelength, diameter and turns as one configuration |
| Choosing 56 mm because it appears to be a higher grade | More space and fiber may be used without proving the required retardance | Treat diameter as geometry; evaluate curvature, winding and envelope together |
| Copying a winding from another diameter or product image | The loaded length and induced retardance change | Use a configuration-specific winding instruction or engineering review |
| Reading 480 to 2400 nm as one universal build | A platform range can be mistaken for one fiber configuration | Map the quoted wavelength to the supplied fiber and winding |
| Comparing a typical IL value with a maximum IL limit | Unlike values create a misleading supplier comparison | Label each value as typical or maximum and define wavelength, method and reference plane |
| Using controller loop diameter as the fiber minimum bend radius | Product geometry is mistaken for a general fiber handling rating | Review bend-loss and handling evidence for the exact fiber and wavelength |
| Applying preloaded-assembly performance to an empty controller | User loading, clamps and routing are outside the stated assembly boundary | Define the supplied condition and the evidence that applies to it |
| Checking body dimensions only with paddles parked | The controller may collide with nearby hardware during adjustment | Review the full paddle sweep, connector clearance and lead routing on the drawing |
| Accepting “FC connector” as a complete interface | Polish, mating interface and key details can remain ambiguous | Specify FC/PC or FC/APC, the mating interface, key requirement and lead length |
| Reordering from an old quote without revision control | Fiber, drawing or acceptance conditions may drift between orders | Reference the approved datasheet, drawing and quotation revision on the purchase order |
Testing and quality-control requirements
Define acceptance for the quoted configuration. State:
- Test wavelength or band
- Exact fiber and cover construction
- Winding pattern and loop diameter
- Device-under-test boundary, connector build and measurement reference plane
- Required insertion-loss and return-loss limits
- Optical source condition relevant to the power requirement
- Sample plan and report format
- Drawing and datasheet revision governing the order
Ask BWNFiber to list the checks and documents included with the quoted build. If the approved specification does not name a test method, certification or lot-acceptance limit, the page should not claim one.
If the approved test plan uses an external method, identify the exact edition and procedure. IEC 61300-3-4:2023 describes attenuation measurements for optical components, while IEC 61300-3-6:2008 covers return-loss measurements for a device under test. Referencing either standard does not establish BWN-FPC compliance unless the quotation adopts it for the supplied build.
Related BWNFiber resources include fiber optic test equipment and tools and a general fiber optic cable testing guide. The cable guide provides background only; it does not define BWN-FPC acceptance.
Packaging and procurement information
Pricing depends on the configuration. The public page does not state MOQ, sample availability, lead time, export packaging, labeling, serial-number options or included documents. Ask for these terms with the optical configuration and quantity.
Separate prototype and production quantities in the RFQ. The returned quotation should state the supplied configuration, price, MOQ, lead time, packaging and included documents.
For an international RFQ, also state:
- Destination country and delivery location
- Requested quotation currency and Incoterm
- Required drawing units and document language
- Required customs, country-of-origin or product-compliance documents
- Any storage, transport or operating conditions outside a controlled laboratory
- Required labeling, packing-list or serial-number format
- Requested delivery date and whether partial shipment is acceptable
These are buyer requirements, not published BWN-FPC capabilities. BWNFiber should confirm each applicable item in the quotation. Do not infer environmental suitability or compliance from the destination region alone.
Planning a prototype or production order? Ask whether a prototype unit is available for the proposed configuration. Request separate prototype and production quantities, commercial terms and document scope; sample availability is not published and must be confirmed.
Recommended downloads
Until approved public files are linked on the page, request these documents for the proposed configuration rather than assuming they are available as standard downloads.
| Document | Minimum useful content |
|---|---|
| Configuration-specific datasheet | Approved fiber, wavelength, loop diameter, winding, leads, termination and accepted optical values |
| Dimension and loading drawing | Fiber-path diameter, narrowest and widest envelope, mounting points, lead orientation, clamp locations and paddle sweep |
| Loading instruction for an empty controller | Compatible cover construction, turn sequence, clamp method and handling precautions |
| Test documentation | Configuration, measurement conditions, reference plane and agreed IL, RL or other results |
| BWN-FPC RFQ worksheet | All optical, mechanical, quantity and document inputs needed before pricing |
From inquiry to an approved BWN-FPC purchase configuration
Use one controlled configuration record from the first inquiry through the purchase order. This reduces the risk of approving one optical build and ordering another.
| Stage | Buyer action | What to request from BWNFiber | Approval gate |
|---|---|---|---|
| 1. Define the requirement | Submit the application, monitored response, wavelength, exact fiber, controller geometry, leads, interface and quantity | Confirmation of received configuration inputs and identification of missing fields | No technical proposal while critical fields remain ambiguous |
| 2. Review the proposed build | Resolve the loop diameter, paddle count, winding and supplied condition | A proposed BWN-FPC build with configuration-dependent items identified | Fiber, wavelength, diameter and winding are reviewed together |
| 3. Compare technical and commercial terms | Compare the proposal against the quotation baseline on this page | Price, MOQ, lead time, packaging, quote validity and available documents for that build | No comparison against a differently defined controller |
| 4. Request evidence or a prototype | Request the datasheet, drawing, loading instruction or available test record; ask whether a prototype is available | A list of documents and prototype terms that can actually be supplied | Do not assume every document or sample is standard |
| 5. Freeze acceptance | Agree the optical limits, conditions, reference plane, sample plan and governing revisions | Approved quotation, configuration datasheet and applicable drawing/test references | Typical catalog data is not used as a lot-acceptance limit |
| 6. Place and repeat the order | Reference the approved model family, configuration and document revisions on the PO | Confirmation of supplied configuration and commercial terms | Any later fiber, winding, interface or document change triggers reapproval |
The expected output of a BWNFiber configuration review should be a clearly identified proposed build, the available evidence for that build, unresolved items, and configuration-specific commercial terms. Ask for each item explicitly; this page does not imply that every document, prototype or option is available for every configuration.
Frequently asked questions
Which polarization controller loop diameter should I choose?
Choose the diameter only after confirming the exact fiber, operating wavelength, required winding, paddle count and available installation envelope. BWNFiber lists 18 mm for two paddles and 27 or 56 mm for three paddles.
Is a 56 mm loop always the safest option?
No. It reduces curvature but requires more space and more fiber per turn. Check the fiber, wavelength, winding and mechanical layout before approval.
Can I change from 27 mm to 56 mm without changing the winding?
Do not assume so. Moving to 56 mm changes curvature and fiber length per turn, so the original winding may no longer produce the intended retardance. Re-evaluate it for the target fiber and wavelength.
Which loop diameter is best for 1550 nm?
There is no universal 1550 nm diameter. Specify the fiber, diameter and turns as one configuration; more than one geometry may work when the winding is designed for that build.
How much fiber should I order?
Estimate the looped length from π × diameter × total turns, then add internal routing, both external leads and the handling allowance defined by the loading instruction. Use the approved drawing for the final quantity.
Should I choose two or three paddles?
The published two-paddle option uses the compact 18 mm layout. Select three paddles when the setup needs the quarter-wave, half-wave and quarter-wave adjustment sequence, then choose between 27 and 56 mm by fiber and mechanical requirements.
What fiber and cover options are published?
The public page lists application-matched single-mode fiber, a standard 0.9 mm tube and a 3 mm jacketed option. State the exact fiber and cover in the RFQ so BWNFiber can check the selected loop geometry.
What connector options are available?
BWN-FPC can be ordered without connectors or with FC/PC or FC/APC terminations. State the mating interface, key requirement and lead lengths.
Does the 480 to 2400 nm range apply to every configuration?
No. It is a platform range across configurable builds. One unspecified fiber and winding should not be read as covering the full range.
What insertion loss and return loss are published?
The public page lists 0.2 dB typical insertion loss including connectors and 55 dB return loss with FC/APC connectors. The quote still needs a maximum limit, wavelength, reference plane and test method.
Can BWN-FPC actively stabilize or lock polarization?
BWN-FPC is a manual paddle controller. A system that needs continuous stabilization, remote adjustment or a documented lock requires a different control category.
What should I send for a quote?
Send the operating wavelength, exact fiber, cover construction, paddle count, loop diameter, winding requirement, input and output lead lengths, connector termination, prototype and production quantities, and required acceptance documents.
Request a BWN-FPC configuration review
Send the full configuration with the product name. Request that BWNFiber identify the proposed build, available documents, unresolved conditions and the commercial terms for that assembly.
RFQ inputs
- Wavelength or band and source condition
- Exact fiber designation and cladding or cover construction
- Two- or three-paddle preference
- 18, 27 or 56 mm loop preference, if already defined
- Turns per paddle or a request for winding review
- Input lead, output lead and total fiber requirement
- No connector, FC/PC or FC/APC termination
- Prototype quantity and production forecast
- Required drawing, datasheet and acceptance records
What to request in the response
- Proposed BWN-FPC configuration and any deviation from the submitted requirement
- Available configuration datasheet, drawing, loading instruction and test documentation
- Items that remain subject to engineering or commercial confirmation
- Prototype availability, production quantity basis, price, MOQ, lead time and packaging
- Quotation, datasheet and drawing revisions that should govern the purchase order
Request BWN-FPC manual fiber polarization controller pricing and a configuration-specific datasheet. The memorable buying rule is simple: approve the configuration record, not only the family name or loop diameter.
Submit these details through the BWNFiber inquiry form so engineering and purchasing can review the same configuration record.
