Fluoride Glass Optical Fiber

Single Mode and Multimode Fluoride Fiber Manufactured In-House
Transmissive from the UV to 5.5 µm
Stable in Typical Lab Environments and Easy to Handle
Core Refractive Index Similar to Silica Glass

Multimode Fluoride Bare Fiber

Fluoride Fiber Cross Section

(Not to Scale)

Custom Ruggedized Fluoride Patch Cable

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Overview
Manufacturing
Specs
Graphs
Dual-Clad Fiber
Feedback

Fluoride Optical Fiber Manufacturing Overview

Applications

Spectroscopy
Fiber Lasers
Supercontinuum Light Sources
Environmental Monitoring
Surgical Lasers
Chemical Sensing
IR Imaging

Indium Fluoride and Zirconium Fluoride Fiber Comparison

Click for Details
Click for Raw Data
Typical attenuation for fluoride and silica fiber is plotted above. For information on run-to-run variations, please see the Graphs tab.

Features

Fluoride Glass Fibers Manufactured at Thorlabs' Fiber Draw Facility
- ZBLAN (ZrF₄) for 285 nm - 4.5 µm
- Indium Fluoride (InF₃) for 310 nm - 5.5 µm
World-Class Attenuation, Mechanical Strength, and Geometry Control
Fiber Bundles and Reflection/Backscatter Probes Available
Flexible Manufacturing Processes for Catalog and Custom Products (See Manufacturing Tab for Details)

Thorlabs manufactures an extensive family of mid-IR fluoride fiber using proprietary techniques that provide world-class purity, precision, and strength. These techniques give us excellent control over the fibers' optical and mechanical properties, allowing a wide range of configurations to be drawn. For details, please see the Manufacturing tab.

Based upon ZBLAN (fluorozirconate) or InF₃ (fluoroindate) glasses, our fluoride fibers feature high transmission over the 285 nm - 4.5 µm or 310 nm - 5.5 µm spectral range, respectively. Fluoride fibers offer flat attenuation curves in the mid-IR wavelength range (see the Graphs tab), aided by an extremely low hydroxyl ion (OH) content. The refractive index of fluoride glass is near that of silica; therefore, optical fibers manufactured using fluoride glass exhibit lower return losses and Fresnel reflections than chalcogenide glass fibers.

Products available from stock with same-day shipping include single mode and multimode patch cables, as well as bifurcated fiber bundles for transmission applications and reflection/backscatter probes designed for spectroscopy. Bare fluoride fiber is available upon request by contacting Tech Sales.

Custom Fluoride Fiber and Patch Cables

If our standard offerings do not meet your needs, please contact us to discuss customization and potential fiber draws. Some of the many customization options we provide for fluoride fibers and patch cables include:

Bare Fiber

Hand-Selected Extra-Low-Loss Fluoride Fibers to Meet Strict Attenuation Requirements
Custom Core and Cladding Geometries
Dual-Polymer Claddings Available
Increased Power Handling Capabilities

Patch Cables

Custom Options: Fiber Type, Length, Termination, and Tubing
OEM Patch Cables: Designed for Application Requirements
AR-Coated Patch Cables
Ruggedized Cabling for Harsh Environments

Fluoride Patch Cables from Stock

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A Thorlabs engineer mixes raw materials in our fluoride glass fabrication facility.

Thorlabs manufactures ZBLAN zirconium fluoride (ZrF₄) and indium fluoride (InF₃) fibers at our vertically integrated fiber draw facility. The facility handles raw materials, glass preforms, fiber draw, and patch cable production, all in the same location. By controlling the process from start to finish, Thorlabs can ensure fibers consistently meet world-class specifications, including low attenuation, high mechanical strength, and precise geometry control.

The facility, located in Newton, NJ, USA, is well-equipped for high-volume manufacturing and is capable of producing many kilometers of fiber with consistent performance. In addition, because the fiber stays within Thorlabs' facilities from start to finish, the manufacturing process can be adjusted to accommodate unique custom orders or R&D needs.

Fluoride Characteristics
Fluoride fibers are ideal for transmission in the mid-IR wavelength range, and Thorlabs' fibers feature low attenuation over this range as a result of stringent manufacturing processes yielding an extremely low hydroxyl ion (OH) content. Fluoride fibers also have lower refractive indices and lower chromatic dispersion when compared to other fibers that offer transmission in the mid-IR range, such as chalcogenide glass fibers. Thorlabs' tightly controlled processes mitigate scattering and point defects in the fiber, as well as eliminate micro-crystallization in the glass matrix.

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A Glass Drop During the Fiber Draw Process

Fluoride Fiber Characterization and Testing
In addition to manufacturing fiber, Thorlabs offers testing and characterization services for our fiber products. We precisely measure the properties of each drawn fiber to ensure that it meets our high standards of quality. Extensive testing also provides feedback for our fiber draw team, enabling tight control of each step in the manufacturing process. Customers can request custom testing of any Thorlabs-manufactured fiber, which is then provided with the shipped fiber. Testing of third-party fiber samples provided by customers is also available upon request. Available tests and services include:

Spectral Attenuation Measurement
- UV / Visible / NIR / MIR Wavelength Range
- SM or MM Fiber and Bulk Glass
SM Fiber Cutoff Wavelength Measurement
Fiber NA Measurement
Fiber Glass / Coating Geometry Measurement with Sub-µm Accuracy
MIR High-Power Screening for MM Fibers
Fiber Tensile Strength Testing
Defect / Break Analysis
Degree of Cure Testing for Fiber Coatings

Request testing for Thorlabs or third-party fibers by contacting Tech Sales.

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These graphs show Thorlabs' steady improvement in the average attenuation of all fiber draws during the given year.

Technical Team
Thorlabs' team of MIR fiber researchers and engineers has many years of experience in fluoride glass research and development, production, and fiber draw. Their knowledge and expertise have resulted in consistent improvement in the quality of our fluoride fiber. See the graphs to the left for the progression of our fluoride fiber performance.

Custom Fluoride Fiber and Patch Cables
If our standard offerings do not meet your needs, please contact Tech Support to discuss customization and potential fiber draws. Some of the many customization options we provide for fluoride fibers and patch cables include:

Bare Fiber

Hand-Selected Extra-Low-Loss Fluoride Fibers to Meet Strict Attenuation Requirements
Custom Core and Cladding Geometries
Dual-Polymer Claddings Available
Increased Power Handling Capabilities

Patch Cables

Custom Options: Fiber Type, Length, Termination, and Tubing
OEM Patch Cables: Designed for Application Requirements
AR-Coated Patch Cables
Ruggedized Cabling for Harsh Environments

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Thorlabs' Fiber Draw Tower

Single Mode Fluoride Fiber

SM Operation Begins around Transmission Cutoff Wavelength of Silica Fiber
SM Operation Ends at Multiphonon Edge of the Glass Material
Also Transmit Down to UV (Multimode Operation)
SM Fibers Available with Custom Core Sizes and Cutoff Wavelengths

Fiber Identification #^a	Fiber Type	Transmission Range	SM Operating Wavelength	Cutoff Wavelength	Typical Attenuation^b	Maximum Attenuation	NA^c	MFD^d
IRZS23	Fluorozirconate (ZBLAN)	285 nm - 4.5 µm	2.3 - 4.1 µm	≤2.3 µm	0.03 dB/m @ 2.5 µm	<0.2 dB/m (from 2.3 to 3.6 µm)	0.19 ± 0.02 @ 2 µm	10.5 ± 0.5 µm @ 2.5 µm
IRFS32	Fluoroindate (InF₃)	310 nm - 5.5 µm	3.2 - 5.5 µm	≤3.2 µm	0.15 dB/m @ 3.6 µm	<0.45 dB/m (from 3.2 to 4.6 µm)	0.26 ± 0.02 @ 2 µm	11.0 ± 0.5 µm @ 3.6 µm

Fiber Identification #^a	Core Diameter	Cladding Diameter	Coating Diameter	Core/Clad Concentricity	Core Circularity	Long-Term Bend Radius^e,f	Short-Term Bend Radius^e	Operating Temperature
IRZS23	9 ± 0.5 µm	125 +1/-2 µm	260 ± 15 µm	≤2 µm	≥94%	≥30 mm	≥10 mm	-55 to 90 °C
IRFS32	9 ± 0.5 µm	125 +1/-2 µm	245 ± 15 µm	≤2 µm	≥94%	≥30 mm	≥10 mm	-55 to 90 °C

These fibers are not offered as catalog items, but we have provided these identification #s here for convenience when discussing your order with Tech Sales.
Hand-Selected Extra-Low-Loss Fiber Available Upon Request
Defined by the Index Difference Between the Core and Cladding.
Mode Field Diameter is a nominal value, calculated using the fiber’s typical NA & core diameter.
Proof Testing Available Upon Request
Calculated Values for <0.2% Failure Rate, for a 10 m Length of Fiber over >20 years

Multimode Fluoride Fiber

Wide Selection of Core Sizes in Both ZBLAN and InF₃
All Fibers Transmit from UV to Mid-IR
Available with Custom Core Sizes and Other Fiber Geometry Specs

Fiber Identification #^a	Fiber Type	Transmission Range	Typical Attenuation^b	Maximum Attenuation	NA
IRZM05020	Fluorozirconate (ZBLAN)	285 nm - 4.5 µm	0.15 dB/m @ 2.5 µm	≤0.2 dB/m (from 2.0 to 3.6 µm)	0.20 ± 0.02 @ 2 µm
IRZM10020
IRZM20020
IRZM45020
IRZM60020		285 nm - 4.5 µm	0.2 dB/m @ 2.5 µm	≤0.25 dB/m (from 2.0 to 3.6 µm)
IRFM10026	Fluoroindate (InF₃)	310 nm - 5.5 µm	0.1 dB/m @ 2.5 µm and 3.6 µm	≤0.25 dB/m (from 2.0 to 4.6 µm)	0.26 ± 0.02 @ 2 µm
IRFM20026	Fluoroindate (InF₃)	310 nm - 5.5 µm	0.1 dB/m @ 2.5 µm and 3.6 µm	≤0.25 dB/m (from 2.0 to 4.6 µm)	0.26 ± 0.02 @ 2 µm

Fiber Identification #^a	Core Diameter	Cladding Diameter	Coating Diameter	Core/Clad Concentricity	Core Circularity	Long-Term Bend Radius^c,d	Short-Term Bend Radius^c	Operating Temperature
IRZM05020	50 ± 2 µm	140 ± 2.5 µm	270 ± 15 µm	≤2 µm	≥95%	≥35 mm	≥20 mm	-55 to 90 °C
IRZM10020	100 ± 2 µm	192 ± 2.5 µm	270 ± 15 µm	≤2 µm	≥98%	≥50 mm	≥25 mm
IRZM20020	200 ± 10 µm	290 ± 10 µm	355 ± 15 µm	≤3 µm	≥95%	≥80 mm	≥40 mm
IRZM45020	450 ± 15 µm	540 ± 15 µm	650 ± 25 µm	≤5 µm	≥95%	≥125 mm	≥30 mm
IRZM60020	600 ± 20 µm	690 ± 20 µm	770 ± 30 µm	≤10 µm	≥95%	≥160 mm	≥75 mm
IRFM10026	100 ± 2 µm	192 ± 2.5 µm	287 ± 15 µm	≤2 µm	≥98%	≥50 mm	≥15 mm
IRFM20026	200 ± 10.0 µm	290 ± 10 µm	430 ± 25 µm	≤3 µm	≥95%	≥80 mm	≥40 mm

These fibers are not offered as catalog items, but we have provided these identification #s here for convenience when discussing your order with Tech Sales.
Hand-Selected Extra-Low-Loss Fiber Available Upon Request
Proof Testing Available Upon Request
Calculated Values for <0.2% Failure Rate, for a 10 m Length of Fiber over >20 years

Multimode Dual-Clad Fluoride Fiber for High Power

Dual-Clad Structure with Polymer 2^nd Cladding
Good for High Power; See the Dual-Clad Fiber Tab for More Information
Dual-Clad Fibers Available in ZBLAN and InF₃ with Custom Core Sizes

Fiber Identification #^a	Fiber Type	Transmission Range	Typical Attenuation^b	Maximum Attenuation	NA
IRFH10026	Fluoroindate (InF₃)	310 nm - 5.5 µm	0.08 dB/m @ 2.5 µm and 3.6 µm	≤0.25 dB/m (from 2.0 to 4.6 µm)	0.26 ± 0.02 @ 2 µm
IRFH20026	Fluoroindate (InF₃)	310 nm - 5.5 µm	0.08 dB/m @ 2.5 µm and 3.6 µm	≤0.25 dB/m (from 2.0 to 4.6 µm)	0.26 ± 0.02 @ 2 µm

Fiber Identification #^a	Core Diameter	Cladding Diameter	Second (Polymer) Cladding Diameter	Coating Diameter	Core/Clad Concentricity	Core Circularity	Long-Term Bend Radius^c,d	Short-Term Bend Radius^c	Operating Temperature
IRFH10026	100 ± 2 µm	192 ± 2.5 µm	229 ± 15 µm	287 ± 15 µm	≤2 µm	≥98%	≥50 mm	≥15 mm	-55 to 90 °C
IRFH20026	200 ± 10.0 µm	290 ± 10.0 µm	330 ± 25 µm	430 ± 25 µm	≤3 µm	≥95%	≥80 mm	≥40 mm	-55 to 90 °C

These fibers are not offered as catalog items, but we have provided these identification #s here for convenience when discussing your order with Tech Sales.
Hand-Selected Extra-Low-Loss Fiber Available Upon Request
Proof Testing Available Upon Request
Calculated Values for <0.2% Failure Rate, for a 10 m Length of Fiber over >20 years

Multimode Fluoride Patch Cables Attenuation

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Click for Raw Data
This plot contains the measured attenuation from five independent draws of the Ø200 µm core ZrF₄ fiber. This data is representative of our Ø50 µm, Ø100 µm, Ø200 µm, and Ø450 µm core fibers.

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Click for Raw Data
This plot contains the measured attenuation from five independent draws of the Ø600 µm core ZrF₄ fiber.

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Click for Raw Data
This plot contains the measured attenuation from four independent draws of the Ø100 µm core InF₃ fiber.

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Click for Raw Data
This plot contains the measured attenuation from five independent draws of the Ø200 µm core InF₃ fiber.

Single Mode Fluoride Patch Cables Attenuation

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Click for Raw Data
This plot contains the measured attenuation for our single mode ZrF₄ fiber. The green shaded region in the plot denotes the specified range for single mode operation with attenuation ≤0.2 dB/m, and the blue shaded region denotes the range for single mode operation without a guaranteed attenuation specification. The orange shaded region denotes the range where the fiber is still transmissive, but provides multimode operation. The cutoff wavelength, denoted by a dashed vertical line, is the onset of this multimode operation and will vary from run to run. The peak near 1.9 µm corresponds to attenuation of the second-order mode.

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Click for Raw Data
This plot contains the measured attenuation for our single mode InF₃ fiber. The green shaded region in the plot denotes the specified range for single mode operation with attenuation ≤0.45 dB/m, and the blue shaded region denotes the range for single mode operation without a guaranteed attenuation specification. The orange shaded region denotes the range where the fiber is still transmissive, but provides multimode operation. The cutoff wavelength, denoted by a dashed vertical line, is the onset of this multimode operation and will vary from run to run. The peak near 2.9 µm corresponds to attenuation of the second-order mode.

Zirconium Fluoride SM Bend-Induced Attenuation

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Click for Raw Data
This plot contains the measured attenuation for a single loop of our single mode ZrF₄ fiber at five different bend radii. The green shaded region in the plot denotes the specified range for single mode operation with attenuation ≤0.2 dB/m, and the blue shaded region denotes the range for single mode operation without a guaranteed attenuation specification.

Indium Fluoride SM Bend-Induced Attenuation

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Click for Raw Data
This plot contains the measured attenuation for a single loop of our single mode InF₃ fiber at four different bend radii. The green shaded region in the plot denotes the specified range for single mode operation with attenuation ≤0.45 dB/m, and the blue shaded region denotes the range for single mode operation without a guaranteed attenuation specification.

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Microbend Loss in Dual-Clad Fiber: Light that leaks out of the core propagates within the first cladding. The light exits the fiber over a greater area with lower intensity, avoiding damage to the fiber.

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Microbend Loss in Standard Fiber: Light that leaks out at a single spot has high intensity and can damage the fiber.

Multimode Dual-Clad Fiber for High Power

Second Cladding Creates Additional Waveguide Layer
Reduces Risk of Damage Due to Light Leakage
Ideal for High Power
Contact Tech Sales to Order

Our unique dual-clad fiber is designed for delivery of high power beams. Light propagates in the core of the fiber due to total internal reflection upon hitting the interface with the cladding. In a perfect fiber, the light is reflected completely at each point and propagates through the fiber core. However, certain imperfections can cause light to exit the core and leak into the cladding; such imperfections include bends in the fiber cable, microbends in the layers of the fiber, and defects.

In a single-clad fiber, the light may leak out of the fiber at a single spot. This high-intensity spot can easily burn or otherwise damage the fiber. In contrast, double-clad fiber uses a second cladding as a light guide to distribute some of the light leakage along a length of the fiber. This significantly reduces the risk of damage, as the intensity of the leakage is greatly reduced. The images above illustrate the effect of the second cladding in preventing damage.

See the Specs tab for specifications for our dual-clad fiber, or contact Tech Support to discuss custom dual-clad fiber options.

Posted Comments:

Daniel Humberto Martínez (posted 2021-11-16 02:14:55.273)

Hi, My research group bought a ZBLAN Zirconium Fluoride (ZrF4) fiber (P3-23Z-FC-5), which we use for Supercontinuum Generation. In order to carry out simulations, could you provide us with the non-linear coefficients of the fiber or give us some information or reference in this regard?. I am awaiting your response Thank you

YLohia (posted 2021-11-23 02:04:54.0)

Hello, thank you for contacting Thorlabs. We don’t spec the non-linear coefficient but the value found in the literature for n2 is 2.1 x 10^-20 m^2/W. Please note that Thorlabs doesn't guarantee this value as we have not tested this parameter.

Ye Yujie (posted 2021-05-20 13:38:38.163)

中红外光纤的纤芯、包层折射率和直径

YLohia (posted 2021-05-20 10:22:37.0)

Hello, an applications engineer from our team in China (techsupport-cn@thorlabs.com) will discuss this directly with you.

YLohia (posted 2021-05-20 10:22:37.0)

Hello, an applications engineer from our team in China (techsupport-cn@thorlabs.com) will discuss this directly with you.

Jun Zhao (posted 2020-07-28 17:15:42.74)

Could you suggest and quote for InF3 fiber with core size of 10um?

nbayconich (posted 2020-07-28 11:15:23.0)

Thank you for contacting Thorlabs, I will reach out to you directly to discuss our custom capabilities.

Ian McLaughlin (posted 2019-08-28 14:40:21.59)

Please provide a quote for the Mid-Infrared Optical Fiber

nbayconich (posted 2019-08-28 04:18:38.0)

Thank you for contacting Thorlabs. I will reach out to you directly to discuss our custom capabilities and quote you a custom patch cable. For future custom requests please contact techsupport@thorlabs.com directly or you can request a quote from the "Request Quote" link above the feedback section.

todd (posted 2017-03-03 11:36:46.65)

What is the fluoride fiber buffer material? Is the buffer strippable? Once I know this I will figure out how much fiber I will need a quote for.

tfrisch (posted 2017-03-13 02:41:45.0)

Hello, thank you for contacting Thorlabs. The buffer is acrylate, and I will contact you directly on how the recommended handling differs from silica fibers.

ilindsay (posted 2015-08-27 15:41:39.307)

Hi. Can you comment on the end preparation of your mid-IR (fluoride) fibers, e.g. differences from SiO2 fibers in terms of cleaving and polishing techniques in the case of applications where connectors are not appropriate?

besembeson (posted 2015-09-29 08:59:55.0)

Response from Bweh at Thorlabs USA: We recommend Thorlabs Vytran products, such as the LDC-400 (http://vytran.com/product/ldc-400) for cleaving bare fiber. Polishing is only relevant when terminating fiber with a connector and it is different with these mid-IR fibers. I will follow-up with you for further guidance with these if needed.