Category: In-line Polarizer

Polarizing Perspectives: Unveiling the Inner Workings of In-line Polarizers

Have you ever wondered how certain optical devices can magically filter light to reduce glare, enhance image quality, or even make 3D movies possible? In the fascinating world of optics, one of the key players in achieving these effects is the in-line polarizer. In this article, we’ll take an in-depth journey into the realm of polarizers, exploring their inner workings, applications, and the science behind their mesmerizing feats.

1. Introduction to Polarizers

Polarizers are optical devices designed to control and manipulate the orientation of light waves. By allowing light waves to pass through in a specific direction, polarizers play a pivotal role in a wide range of industries and technologies.

2. Understanding Polarized Light

Before delving into in-line polarizer, it’s essential to grasp the concept of polarized light. Light, which usually travels in all directions, becomes polarized when its waves oscillate predominantly in one plane.

3. Types of Polarization

There are two primary types of polarization: linear and circular. Linear polarization occurs when light waves vibrate in a single plane, while circular polarization involves the rotation of light waves as they propagate.

4. What are In-line Polarizers?

In-line polarizers are specialized optical components that transmit light waves with a specific polarization while blocking or attenuating light waves of other polarizations. They are often used to enhance visual clarity and reduce glare.

5. How In-line Polarizers Work

In-line polarizers employ various techniques, such as dichroism or birefringence, to selectively filter light waves based on their orientation. These devices consist of aligned molecules or microstructures that interact with incoming light to achieve the desired polarization effects.

6. Applications in Everyday Life

In-line polarizers have found their way into numerous aspects of our daily lives. Sunglasses, for instance, use polarizers to reduce glare from reflective surfaces like water or roads, making outdoor activities more comfortable.

7. In-line Polarizers in Photography

Photographers often use polarizers to enhance the quality of their images. By reducing reflections and boosting color saturation, these polarizers enable the capture of stunning landscapes and vivid scenes.

8. The Role of Polarizers in 3D Technology

Polarizers play a crucial role in 3D technology, particularly in stereoscopic cinema. They enable the separation of images intended for the left and right eyes, creating the illusion of depth in 3D movies.

9. Polarizers in LCD Screens

LCD screens utilize liquid crystal in-line polarizers to control the passage of light and create the images we see. The liquid crystals can be manipulated to adjust the polarization state of the transmitted light.

10. Polarization in Physics and Astronomy

Polarization phenomena extend to the field of physics and astronomy. By studying the polarization of light from celestial objects, scientists can gain insights into the properties of stars, galaxies, and interstellar matter.

11. Manufacturing and Technology Behind Polarizers

The production of high-quality in-line polarizers involves intricate manufacturing processes, including precise alignment of molecules or microstructures. Advanced technologies ensure consistent performance and reliability.

12. Challenges in Polarizer Design

Designing effective polarizers comes with challenges. Achieving broad-spectrum polarization, reducing energy loss, and adapting polarizers for specific environments are some of the ongoing design considerations.

13. Advancements and Future Possibilities

As technology advances, new applications for in-line polarizers continue to emerge. From augmented reality to medical imaging, these devices hold the potential to revolutionize various industries.

14. Making the Right Choice: Selecting Polarizers

Choosing the appropriate in-line polarizer depends on factors such as intended application, wavelength range, and desired polarization efficiency. Careful consideration ensures optimal results.

Conclusion

In-line polarizers stand as remarkable tools that manipulate light to serve a myriad of purposes. From enhancing visual experiences to advancing scientific research, these devices unlock a world of possibilities through the precise control of polarized light.

How to Enhance Optical Systems with In-line Polarizers?

Introduction

Optical systems play a crucial role in various industries, from photography and telecommunications to medical and scientific fields. These systems rely on the precise manipulation of light to achieve desired outcomes. In-line polarizers, a type of optical component, have gained significant importance for enhancing optical systems. In this article, we will explore the fundamentals of in-line polarizers, their functioning, and how they can be effectively used to improve optical setups.

Understanding Optical Systems

Before delving into in-line polarizers, it is essential to understand the basics of optical systems. An optical system is a collection of components that interact with light to modify its properties, such as direction, intensity, or polarization. Common optical elements include lenses, mirrors, filters, and polarizers, all working together to control light behavior.

What are In-line Polarizers?

An in-line polarizer is an optical device used to filter and transmit light of a specific polarization while blocking light with different polarizations. It allows only the desired polarized light to pass through, resulting in more controlled and refined optical output.

Importance of In-line Polarizers in Optical Systems

In-line polarizers are invaluable tools in optical systems due to their ability to manage light polarization. By selectively allowing certain polarizations, they enable better control over optical pathways, leading to improved image quality, reduced glare, and enhanced signal transmission.

Types of In-line Polarizers

There are several types of in-line polarizers available, each with its own unique properties and applications. Some common types include:

Polaroid Sheets

Polaroid sheets are made of stretched polymer material that selectively transmits polarized light. They are cost-effective and find use in photography and 3D glasses.

Wire-grid Polarizers

Wire-grid polarizers consist of fine metal wires arranged in a grid pattern. They are widely used in LCD displays and imaging applications.

Glan-Taylor Prism Polarizers

Glan-Taylor prism polarizers utilize birefringent crystals to separate polarizations. They are commonly used in laser systems and polarimetry.

Glan-Laser Prism Polarizers

Glan-Laser prism polarizers are an enhanced version of Glan-Taylor polarizers, providing better performance at higher laser power levels.

How Do In-line Polarizers Work?

The working principle of in-line polarizers is based on the selective absorption and transmission of polarized light. When unpolarized light passes through an in-line polarizer, only the component with the desired polarization orientation can pass through, while the orthogonal component is absorbed or blocked.

Factors to Consider When Choosing In-line Polarizers

Selecting the right in-line polarizer for a specific application requires considering various factors:

Wavelength Range

Ensure that the polarizer operates within the required wavelength range for your optical system.

Polarization Efficiency

Higher polarization efficiency leads to better light control and minimal loss of light intensity.

Extinction Ratio

A higher extinction ratio indicates better polarizer performance in blocking undesired light.

Temperature Stability

Some applications demand polarizers with excellent stability under varying temperature conditions.

Applications of In-line Polarizers

In-line polarizers find versatile applications in different industries:

Photography and Camera Lenses

In-line polarizers help improve color saturation and reduce reflections in photographs.

LCD Displays and Monitors

They enhance the contrast and clarity of images displayed on LCD screens.

Fiber Optics Communication

In-line polarizers play a role in maintaining polarization alignment in fiber optic communication systems.

Laser Systems

They are vital components in laser setups, ensuring precise polarization control.

Microscopy

In-line polarizers aid in extracting valuable information during polarized light microscopy.

Tips for Enhancing Optical Systems with In-line Polarizers

To make the most of in-line polarizers, consider the following tips:

Proper Alignment

Ensure accurate alignment of the polarizer within the optical system to achieve optimal performance.

Maintenance and Cleaning

Regularly clean and maintain polarizers to avoid performance degradation due to dust or debris.

Polarizer Combinations

Experiment with different combinations of polarizers to achieve specific polarization states.

Dealing with Light Loss

Account for light loss when designing optical setups with in-line polarizers.

Common Challenges and Troubleshooting

While using in-line polarizers, some common challenges may arise:

Glare and Reflections

Improper placement of polarizers can cause unwanted glare and reflections.

Polarizer Damage

Physical damage to polarizers can lead to decreased efficiency or complete failure.

Compatibility Issues

Ensure compatibility between polarizers and other optical components in the system.

Conclusion

In-line polarizers are indispensable tools for enhancing optical systems across various industries. With their ability to control light polarization, they enable improved image quality, reduced glare, and enhanced signal transmission. By understanding the different types, working principles, and factors to consider, one can effectively leverage in-line polarizer for their specific optical requirements.

A Concise Selection Guide for In-Line Polarizers

How do I select the right in-line polarizers? If you also have the same question in mind, then this guide will help you learn all those things that you should know for choosing the best in-line polarizers for your applications. But why do you need to buy only the best in-line polarizers? Why does their quality matter?

In-line polarizers are the small and compact fiber optic devices placed in line to improve and enhance the extinction characteristics of a fiber optic cable. They are designed to allow only one pre-defined polarization state and block the transmission of all other polarization states. Their use in many industries has become vital because if polarization extinction degrades in the fiber, it can lead to significant noise interference and reduce the performance of the entire fiber optic system.

Thus, one should never cut corners when buying in-line polarizers and should choose only the highest quality. So, without any delay, let’s find out how to buy the best in-line polarizers.

Things to Consider When Choosing the Best In-Line Polarizers

  • Polarization

It is no secret that light waves are highly susceptible to noise and interference, which is very harmful to the fiber optic systems’ performance and quality. Thus, to avoid unwanted interference and improve the performance of signals, in-line polarizers that have better control on the transfer of desired polarization state and block unwanted polarization states are considered the best choice. In short, it must transmit only linearly polarized light with a high extinction ratio and low insertion loss.

  • Signal Characteristics

The next thing you need to keep in mind includes signal characteristics. All fiber optic systems transmit light waves characterized by wavelength. Besides, a light signal is also characterized by the optical power of the signal, which is measured in dBm or mW. Due to the nature of the transport medium (i.e. fiber), fiber optic systems transmit usually longer light waves from red (650nm) to the infrared region. That’s why you see 650 nm in-line polarizers, 980nm in-line polarizers, etc. on the market.

Shorter wavelengths get perturbed due to scattering of the light source, and absorption bands at certain frequencies further attenuate the signal. Therefore, long wavelengths work better for fiber optic systems.

  • Optical Power

Optical power is the measure of wavelength and photon density. Usually, low-power signals are used in fiber optic systems. The most common units used for optical power are dBm or mW (milliwatts). A power level of 0 dBm is equivalent to 1mW, -10 dBm is 0.1 mW, and +10 dBm is equivalent to 10 mW.

  • Preferred Cable Type

In fiber optics, there are two cable types: single mode optical fiber and multimode optical fiber. While single-mode fiber cable allows a single path for light, multimode fiber cable offers multiple paths for light. It is important to note that multimode fiber cables limit the distance that a signal can travel as multiple paths of transmission force the different modes of light to disperse, and hence, they also limit transmission bandwidth. On the other hand, single-mode fiber cables facilitate signal transmission at very high bandwidth and long transmission distances.

If you need high-quality 980nm in-line polarizers or in-line polarizers with other wavelength requirements, get in touch with DK Photonics.

What does polarization refer to in polarization maintaining components?

In polarization maintaining components, there is a huge rule of polarization as it influences the performance of these components, the quality of the signal transmitted across the network, and their desirability in certain applications. So, if you wonder about what this polarization means in optical fiber communication networks, this blog is a must-read for you.

What is the meaning of polarization in optical fiber communication?

A light beam is composed of two electrical vector field components that are orthogonal to each other. These components vary in terms of frequency and amplitude. We call a light beam polarized when these two components vary in amplitude (or phase).

Polarization in optical fibers has been extensively researched and studied, and now, we have a variety of ways to either minimize this polarization or maximize it to take advantage of polarization, depending on our requirements.

Meaning, in polarization maintaining components, components are designed using optical fibers to maintain polarization to take advantage of this phenomenon.

When talking about polarization, there is another term that you should know about for better understanding.

Birefringence

This phenomenon occurs in certain types of materials that can split a light beam into two different paths. It happens because these materials have different indices of refraction based on the polarization direction of the light. This phenomenon is also seen in optical fibers because of the slight asymmetry in the cross-section of the fiber core and external stresses exerted on fiber due to bending. In general, birefringence is induced more often by external stresses than the geometry of the fiber.

A specialty fiber that maintains polarization creates a consistent birefringence pattern along its length intentionally, and thereby prevents the coupling between two orthogonal polarization patterns. In any fiber design, the geometry of the fiber and materials used in the formation of fiber creates a lot of stress in one direction and hence produces higher birefringence as compared to the random one.

In the market, a number of designs with stress-inducing architectures, such as Panda and Bow Tie PM Fibers with different cut-off wavelengths are available for commercial use.  

Did you know polarization is characterized by some measurable properties? We have enlisted some of these properties below:

  • Extinction Ratio: It is expressed in dB and refers to the ratio of minimum polarized power and maximum polarized power.
  • Polarization Dependent Loss: Also expressed in dB, it is the maximum peak-to-peak variation in insertion loss.
  • Polarization Mode Dispersion: It is another form of material dispersion.

Since the fiber core is not perfectly circular in general and it is exposed to mechanical stresses that induce birefringence in the fiber, it causes one of the orthogonal polarization modes to travel faster than the other. This, in turn, causes dispersion of the optical pulse.

The maximum difference in the times of the mode propagation caused by dispersion is known as differential group delay, which is typically expressed in picoseconds.

How Does Birefringence Affect the Polarization in Optical Fibers?

Applications that involve the transmission of data and light guiding are highly benefitting from fiber optic cables as they can safely transmit data at a wide bandwidth over long distances. This is why they find huge demand in industries like medical, military, and networking. Since unpolarized light travels through optical fibers with considerable losses and distortions, especially over long distances, it is critical to use polarized light in fiber optic cables for data transfer. To solve this problem, in-line polarizers are used as they help in facilitating the strongest and cleanest output signal. 

In-Line Polarizers – An Ideal Solution to Minimize Losses and Distortions

In-line polarizers are small pieces of cable in fiber capable of polarizing the incoming light signals. These devices are called in-line polarizers because they are positioned in-line with the fiber. Fiber with polarization controlled capacity can produce output signals with optimum intensity and bandwidth without causing any hindrance in velocity. 

Birefringence – How is it related to polarization in fibers?

Birefringence is an important property of optical materials where the refractive index is dependent on the incoming light’s polarization. This property is most commonly found in nonlinear crystals and various optical fibers as well. Though fiber cores with perfectly circular shape are considered to be ideal, most fibers in practical suffer mechanical stresses caused by bending or handling. This results in shifted geometry and that further leads to polarization-mode distortion along the length of single and multimode fibers. As a result, one polarization mode travels at a different space than the other. 

But, the question is how can birefringence affect the performance of optical fibers? 

Pulses lengthened due to birefringence produce noisier and lower quality output light signals. Since different polarizations of light can be absorbed by different materials at different angles, it becomes necessary to have control over polarization, particularly in optics applications because light polarization affects the focus of laser beams and which, in turn, influences the cut-off wavelengths of fibers. So, controlled polarization is critical to prevent undesired back reflections. 

Factors to Consider While Buying In-Line Polarizers

  • Insertion Loss: When a fiber optic polarizer is introduced in a system, it certainly causes attenuation. A good in-line polarizer is the one that causes minimized resultant loss. 
  • Bandwidth: Since different bandwidths are used in different applications, you must choose an in-line polarizer and fiber that can accommodate desired bandwidth.
  • Size: Usually smaller in-line polarizers are preferred because of the space constraints. Besides, they also come with lower insertion loss. 
  • Extinction Ratio: It is the ratio of the transmission of the desired polarization to the transmission of undesired polarization. Thus, it is the best indicator of quality for an in-line polarizer. 

Do you also need in-line polarizers? Keep in mind the above four factors to decide which one is the best for your application. 

Top Features and Applications of In-line Polarizers

When it comes to data transmission and light guiding applications, you can rely on fiber optic cables. They play a vital role in constituting a complete network that is used for transmitting data over long distances at a wide range bandwidth. Fiber optic technology is considered to be ideal for medical, networking, military, electronics, communications, and various other applications.

Though light waves (polarized or unpolarized), can travel through optical fibers with ease, losses are experienced with unpolarized light. Unpolarized light waves travel with significant losses and distortions especially for long distances and this can be detrimental for transmitting information.

To avoid such issues, fiber optic polarizers are used because they can provide the strongest and cleanest output signal.

In this blog, we will explore what these fiber optic polarizers are, what features they have, and where these devices are used.

What is Fiber-Optic Polarizer?

Fiber optic polarizers are small pieces of cable placed in-line with fiber that helps in polarizing the incoming light wave/signal. Fiber with controlled polarization yields output with maximum intensity and bandwidth without disturbing the velocity.

The term that is quite popular with fiber optic technology is in-line polarizer.

In-line polarizers are specially designed to pass the light with specific polarization while blocking the orthogonal polarization. They help in the conversion of unpolarized light into polarized light with a high extinction ratio.

Generally, the standard configuration used for these polarizers is single-mode fiber for input and polarization-maintaining fiber for output.

Features of In-line Polarizers

The salient features that define high quality in-line polarizer are as follows:

  • Low insertion loss
  • Very small in size
  • High extinction ratio
  • Excellent reliability
  • High power handling ability
  • Very affordable
  • Superior performance

Available Versions of In-line Polarizers

The two versions of in-line polarizers are available in the market:

Pigtailed In-line Polarizer

This version of in-line polarizer comes with ~1 m long fiber pigtails with a 900 µm tube. The benefit of using pigtail in-line polarizers is that they are more economical and provide the user with added length for use in the fiber optic system.

Bulkhead In-line Polarizer

This in-line polarizer version is widely famous for being rugged. It does not have any pigtails. Since there are no pigtails, this makes polarizer handling easier. There is no need to worry about handling fragile fibers. Besides, it comes with the advantage of removing polarization disturbances caused by pigtails.

Applications of In-line Polarizers

  • Analysis of polarization
  • Monitoring and control of polarization
  • SNR (Signal-to-Noise Ratio) Monitoring
  • PMD (Polarization Mode Dispersion) Monitoring
  • PER (Polarization Extinction Ratio) Monitoring
  • Polarization interferometry
  • Spectrum filtering and control
  • Fiber laser mode-locking

If you also need in-line polarizer for your application or have any query related to it, contact a reputed online in-line polarizer supplier to ensure high quality or gain insights.

7 Crucial Factors of Choosing a Polarizer

Polarization is a crucial aspect of light, and there polarizers – key optical elements used to control polarization. They work to transmit a desired polarization state while reflecting, absorbing or deviating the rest.  There are various polarizer designs, with each having their own advantages and disadvantages. Here we will look at some of the key factors that you should look in order to choose the perfect polarizer for you.

Factors to keep in mind when selecting a polarizer:

Extinction Ratio and Degree of Polarization: The polarizing properties of the best in-line linear polarizer to buy depend upon the degree of polarization or polarization efficiency and its extinction ratio.

So it is crucial to measure the extinction ratio typically which may  vary with wavelength, incident angle along with other factors like cost, size, and polarized transmission for a given application.

Transmission: This refers to the transmission of light in-line polarized the polarization axis direction. This also may refer to the transmission of un-polarized light through the polarizer. For ideal transmission of such polarization is 100%, parallel transmission should be 50% and crossed transmission 0%.

Acceptance angle: This is the largest deviation from design incidence angle at which the polarizer can still perform well as required. Most polarizers can work at an incidence angle of 0° or 45°.

The acceptance angle is important for alignment, and this is more so when it comes to non-collimated beams. Keep this in mind and choose your in-line polarizer which meets your requirements.

Construction: There is a wide range of forms and designs available. For example, thin film polarizers are thin films similar to optical filters. There are thin flat polarizing plate beam splitters placed at an angle to the beam. And polarizing cube beam splitters have two right angle prisms which are mounted together at the hypotenuse. Get the details of polarizer structure to be sure you choose the right one for you.

Clear aperture: This feature often comes with birefringent polarizers. There are optically pure crystals that limit the size of these polarizers. Choose the size of clear aperture according to your needs. Dichroic polarizers come with largest clear aperture.

Optical path length: The length light which is crucial for dispersion, damage thresholds, and space constraints should travel through the polarizer. There is ideal optical path length in birefringent polarizers but likes of dichroic polarizers lack this.

Cost: This is most important factor to look at when it comes to in-line polarizers. The polarizers which come with large, very pure crystals are expensive while the ones made of stretched plastic are a bit more cost effective.

In addition, there are many other factors that may affect the cost, such as place you buy your polarizer from. If you are looking for quality in-line polarizers with features like low insertion loss, high power handling, high extension ratio at a competitive price in China, DKPhotonics is the right choice for you. It is a leading name providing a wider range of quality optical passive components to suit different needs.

Role of an In-Line Polarizer in Communication System

In the telecommunication industry, the use of optical devices has increased dramatically as they offer high performance, optimum efficiency and excellent reliability. But the truth is that deploying light waves is not easy because they are highly susceptible to noise and interference. Fortunately, these issues can be resolved by the use of fiber optic polarizers. They greatly enhance the signal performance in fiber optic systems by suppressing unwanted interference patterns.

Fiber optic polarizers are placed inline so that the extinction characteristics of the fiber optic cable get improved. Due to their inline placement, these are also called in-line polarizers. The good thing about these polarizers is that they allow the transmission of only one polarization and block the remaining light which has unpolarized states.

So, to maintain the polarization and decrease the degradation in polarization, optical polarizers are necessary. Otherwise, there will be noise interference and the performance of the entire fiber optic system will decrease substantially. An ideal fiber optic inline polarizer is the one which transmits linearly polarized light that has a high extinction ratio and low insertion loss.

Here, linear polarization means the electric or magnetic field is confined to the plane in the direction of wave propagation. Extinction ratio refers to the ratio of the power of a plane-polarized beam transmitted by the polarizer to the transmitted power when polarizer’s axis is perpendicular to the plane of beam and insertion loss is defined as the attenuation caused by the insertion of an optical component.

Characteristics

The light waves transmitted by fiber optic systems are usually characterized by the length of wave i.e. wavelength. The carrier signal is further determined by the signal’s optical power which is measured in dBm or mW.

Wavelength: Human eye can detect wavelengths from 400 to 700 nm which is referred to as visible region. However, fiber optic systems transmit the longer wavelength from red (650 nm) to infrared region. It is caused by the characteristics of the transport medium i.e. the optical fiber. Shorter wavelengths are attenuated due to the scattering effect of light source and they are further attenuated by the absorption bands at specific frequencies.

The main three wavelengths which are used for fiber optic systems are 850, 1300, and 1550nm. 850nm wavelengths are primarily used in plastic optical fiber and multimode fiber. Multimode fiber can also be used to transmit 1300 nm carrier signals, however, single mode fiber can transmit even longer wavelengths such as 1310nm, 1490nm, and 1625nm.

Optical Power: The power of an optical signal is a measure of wavelength and photon density. Fiber optic communication systems use very low power signals. It can be measured in dBm and mW. dBm and mW have logarithmic relationship. The power level of 0 dBm is equivalent to 1 milliwatt.

If you are also searching for fiber optic in-line polarizers, you can easily place an order with a reputed polarizer manufacturer online.

All about In-line Polarizer, Types, and Other Supportive Component

The in-line polarizer is a micro-optic device typically used to convert unpolarized light into polarized one including high extinction ration in the case. It is effectively used to enhance the signal’s extinction ration. A good quality in-line polarizer offers a high extinction ratio, high return loss, low insertion loss, and absolute environmental reliability and stability. It is ideally used in high-speed communication systems and applications like test instrumentation.

There’re two most common types of the in-line polarizer – Pigtail and No-tail.

Pigtail vs. No-tail:

In the pigtail version of the in-line polarizer, input/output fibers are attached to the package, whereas no-tail version often comes with two fiber connectors mounted straight on the package. No-tail version is best for applications where there’s no need for extra fiber length and a number of fiber jumpers/connections are already in the system.

The pigtailed polarizers are best used for fiber systems requiring optical components spliced to the networks or extra fiber is required to fill the gap between the lengths. This version of polarizer provides a great level of flexibility in device mounting and installation. The typical pigtail length is 1 to 2 meters on each side. The diameter of fiber buffer or jacket can be specified by an individual while discussing the requirements with an in-line polarizer manufacturer.

Pigtail fiber type

The pigtailed in-line polarizers have input/output fiber in three types of combinations:

  • SM/SM – Single mode to single mode
  • SM/PM – Single mode to polarization maintaining fiber
  • PM/PM – Polarization maintaining to polarization maintaining fiber

SM/SM fiber pigtailed polarizer works bi-directionally. The input and output ports are exchangeable except if the client determines a special combination of connectors.

SM/PM fiber pigtailed polarizer has the transmission hub of the polarizer adjusted to the slow axes of the polarization maintaining fiber. The output PM fiber is additionally keyed to the slow axes at the connector. Both the fibers are typically marked as ‘SM’ and ‘PM’ before shipment.

PM/PM fiber pigtailed in-line polarizer has (similar to SM/PM) polarizer transmission hub adjusted to the slow axes of both PM fibers. In spite of the fact that the PM/PM in-line polarizer is also bi-directional, it is often advised that client connects the device as indicated by the predetermined input and out directions in order to achieve the best extinction ration. They are also marked before shipment.

Fiber connectors

As per a client’s specification’s fiber connectors can either be SC/PC, FC/PC or FC/APC. Fiber connectors should always be cleaned with the help of fiber connector cleaning techniques followed as per the industry standard.

Following are some in-line polarizer applications

  • Fiber Amplifiers
  • Fiber lasers
  • Fiber Sensor
  • Test and Measurement
  • Communications System

Some of the top features which are common with every polarizer

  • Low Insertion Loss
  • High Power Handling
  • High Extinction Ratio
  • Low Cost
  • High Reliability

You can also add one or more features according to your requirements. In addition, it is advised to choose a trusted supplier who has been providing quality polarizers and other fiber optic products for a long time in your country.

Four Factors to Consider While Buying In-Line Polarizer

Also, known as fiber optic polarizer, an in-line polarizer is indeed a remedy to obtain better quality polarized light for data transmission and light guiding applications. Fiber optic in-line polarizer is ideal to use for medical, networking and military devices because unlike unpolarized light, the polarized light can travel through optical fiber without significant losses and distortions over large distances. Due to their potential use in a vast variety of applications, their demand is increasing rapidly. But before going to a local store or buying an in-line polarizer online, one must know what factors should be considered before making a purchase.

Four Factors That Affect the Performance of In-Line Polarizer

Insertion Loss:

Insertion loss is the most significant factor which decides the quality of light. It refers to the loss of the light signals while traveling in and come out of the optical fiber or you can say a given circuit. The lower value of insertion loss means the higher quality of polarized light. Want to have an idea about the value of insertion loss for in-line polarizer? Alright! The value of insertion loss is usually 0.3 dB (typical) and 0.5 (max.) for 1310 to 1550 nm wavelength and for 1064 nm, it is 0.4 dB (typical) and 0.6 (max.).

Bandwidth:

You will need fiber optic polarizer of different bandwidths for different applications. Thus, according to the application, you need to decide that which optic polarizer and fiber can accommodate the desired bandwidth. While operating wavelength ranges from 630 nm to 2000 nm, the value of bandwidth ranges from ±20 to ±50nm. For your reference, there is a table from which you can determine the bandwidth for your application based on operating wavelength.

Operating Wavelength  (nm) Bandwidth (nm)
630, 850, 980 ±20
1064 ±40
1310, 1550 ±50
2000 ±30

Size of in-line polarizer:

In most of the applications, small-sized polarizers are preferred as they would need less space and space is usually a constraint in any electronic device. Moreover, smaller polarizers also prompt low insertion loss. Thus, I would also recommend you to use a smaller polarizer; unless and until larger one is a necessity for your application.

Extinction Ratio:

Another prominent factor to choose the best quality in-line fiber optic polarizer for any system is the extinction ratio. It is the ratio of transmission of desired polarization to undesired polarization or we can say that this is the ratio of two optical power levels of the digital signal. It can be expressed in three forms i.e. fraction, dB and percentage.

Poorer values of ER lead to increase in Power Penalty (PP), also worsen Bit-Error-Ratio (BER) and also reduce the benefit of increased power. Thus, you should consider in-line polarizer with high extinction ratio. For lower wavelength, typical ER is 30 and min. ER is 23 while for higher wavelength (>=1030 nm), values should be 28 and 25 respectively. These values are just for having an idea about ER value. ER also varies with SM and PM output. Thus, choose carefully.

By now, I hope, you have gathered the necessary knowledge and facts which you should always consider before buying in-line polarizer.