Category: Electronic

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.

How to Buy Optical Fused Coupler: All You Need To Do

Optical coupler is something most important for phonics devices and systems that are meant to combine or split light signals into fibers. The couplers can be either active or passive devices. The passive redistributes the signal without optical-to-electrical conversion while Active couplers split or combine the signals electronically.

When it comes to buying Optical Fused Coupler, there are some crucial factors that you should base your decision.

What you need them for

Before you start searching for Optical Fused Coupler suppliers, get to know where you are going to use them. As each coupler has different features which make them perfect for some certain application, if you know your need, you can choose the coupler equipped with the features essential to cater to your needs.

How they work

A basic fiber optic coupler has two points: N input ports and M output ports. These points will typically range from 1 to 64. But generally, these devices have four-port. How they work depends on the distributed coupling between two individual waveguides in close proximity, and this makes the power gradually transfers between modes which are supported by these waveguides.

 Four ports fiber optic coupler works like this. When light enters into the port 1, it splits into output ports which are port 3 and port 4.  And the port 2 functions in the same way. Sometimes, either port 1 or port 2 remains unused. In such case, the fiber optic coupler acts as a Y or T coupler.

As we have learnt that fiber optic coupler is used to couple or split light, so the coupler is also called fiber optic splitter. The term is used as it, the coupler, splits the light signal.

Where to buy

As you, now, know what you need a coupler for and how a coupler works, you are able to decide on the optic fused coupler. But where you buy it?

There are many fused optical manufacturers and suppliers in China. They make a wide range of couplers for various applications. But choose a manufacture that best suits you.

Check for their clients. This will help you know how they will cater to your needs. If they serve needs of businesses like yours, they are more likely to meet your expectation. Also, make sure if they provide customization. Because. There are many like DK Phontonics that also offer to customize the coupler to meet particular requirements. But make sure the prices offered are reasonable for the quality you get.

PM Optical Circulators: Technology used and Categorization

Since 1990, polarization maintaining optical circulator has become one of the essential components in advanced optical communication systems. Nowadays, its applications have expanded widely not only in telecommunication industry but also in medical and imaging fields. Here, we will discuss this indispensable component in detail. So, let’s start with the basics.

Polarization Maintaining Optical Circulator

What is a PM Optical Circulator?
PM optical circulator is a three or four port non reciprocal passive component which functions similar to an isolator. It transmits the light wave from one port to next port with maximum intensity while maintaining polarization and blocking any light transmission from one port to the previous port. Thus, it is also featured as a unidirectional circulator.

Technology Used in PM Optical Circulators
Polarization Maintaining Optical Circulators are designed on the basis of nonreciprocal polarization rotation of the Faraday effect. As the working of optical circulators is based on several components such as Faraday rotator, birefringent crystal, waveplate and beam displacer, let’s take a quick look at each of them.

Faraday Effect:
It is a magneto-optical effect which explains the phenomenon in which polarization plane of electromagnetic wave (or light wave) is rotated inside a material under magnetic field applied in parallel to the direction of wave propagation. The unique aspect of this effect is that the direction of rotation is independent of the propagation direction of light wave, which implies that rotation is non-reciprocal.

Light Propagation in Birefringent Crystal:
Birefringent crystal is a common material used in the designing of optical circulators. The crystals used in optical circulators are typically anisotropic uniaxial which means they have two refractive indices with one optical axis. The function of this birefringent crystal depends on the propagation direction of light and its optic axis orientation (crystal cutting). The crystals which are generally used include quartz, rutile, YVO4, etc.

Waveplate:
Also called retardation plate, a waveplate is one of the applications of birefringent crystal. It is made by cutting a crystal into a particular orientation. Due to small birefringence, crystal quartz is broadly used for making waveplates.

Beam Displacer:
A birefringent crystal based beam displacer is used to split an incoming light beam into two beams with orthogonal polarization states.

Categorization of Optical Circulators
Optical circulators are mainly divided into two categories:
Polarization-dependent optical circulator
Polarization-independent optical circulator

The former type is only functional for a light wave with a particular polarization state and is only used in a few applications such as free space communications between satellites and crystal sensing.

On the other hand, the latter type is functionally independent of the polarization state of light. While in ordinary circulators, the polarization is not maintained but there are polarization maintaining optical circulators available in the market also. They are used in a large variety of applications.

According to their functionality, optical circulators can also be divided into two groups.
Full Circulator – light passes through all ports in a full circle
Quasi Circulator – light passes through all ports but the light from last port is lost

Fortunately, due to the advancement in technology, you can avail highly reliable and efficient Polarization Maintaining Optical circulators not only in standard specifications but in customized specifications too.

Optical Circulators and Its Passive Optical Components

To fulfill the requirement of communication efficiency, network technicians generally use optical circulator in a fiber optic system as it reduces the loss of light. An optical circulator is a small yet powerful device used in optical communication systems. The device is typically used to separate optical signals that (in an optical fiber) travel in opposite directions.

Functioning Principle and Components

Optical circulators usually consist of a polarizing beam splitter, Faraday rotator, reflector prism, birefringent blocks, and a retardation plate. The functioning of an optical circulator is a little similar to optical isolator. A light which travels in one direction right through the Faraday rotator will have its polarization rotated in one specific direction. A light that enters the rotator from the opposite direction will have its phases rotated in the opposite direction (sometimes may depend upon the propagation direction of the light).

In other words, light always rotates in one direction in accordance with the rotator regardless of its traveling direction.

Three-port optical circulator is widely used so let’s discuss that first. A signal in a three-port optical circulator is transmitted from 1st port to 2nd port where another signal is transmitted from 2nd to 3rd and additionally, a third signal can also be transmitted from 3rd to 1st.

Types

As per the Polarization Characteristics

If we talk about the characteristics based on the optical circulator’s polarization capabilities, they can be divided into two major types:

PM – Polarization Maintaining

PI – Polarization Insensitive

Each PM optical circulator typically comes in the market with a polarization maintaining fiber which makes it an ideal component for applications where it is necessary to maintain polarization, for example, Raman pump applications, 40Gbps systems, etc.

Polarization insensitive optical circulator is a small lightwave component which delivers high-performance functioning. The component comes in the market having features like low insertion loss, high isolation, high stability and reliability, and low polarization-dependent loss (PDL).

It is high in demand in combination with fiber gratings and other reflective components in close-packed wavelength-division multiplexing (DWDM) systems, high-speed systems and bi-direction communication systems.

As per the number of ports availability

Optical circulators fall into three main types when it comes to the number of ports:

3-port

4-port

6-port

3-port and 4-port optical circulators are commonly used way more than the 6-port optical circulations. In such circulators, optical light that is transmitted from any port can easily be redirected to any other port, regardless of the port-type.

An optical circulator is very commonly applied in a long list of applications within a fiber communication system. In modern optical communication systems, the optical circulator is usually used for wavelength division multiplexing networks, optical time domain reflectometers, fiber amplifier systems, bi-directional transmissions, etc.

With primary characteristics such as high isolation, low crosstalk, low insertion loss, and large bandwidth, the optical circulator can also become an in-built component of the same device as transmitters, amplifiers, and receivers.

Achieving highly precise polarization is Easy like Never Before with Insensitive Optical Circulator

There are applications like optical fiber communication networks, fiber optic instruments, and depression compression modules wherein it is vitally important to polarize the lights going in multiple directions into one single direction. Thanks to Insensitive Optical Circulator, it is now pretty possible to achieve the polarization of light into single direction.

Optical circulator is specially designed fiber optic device with an ability to separate optical power traveling in opposite directions in one optical fiber. The optical circulator can also be used to achieve bi-directional transmission over a single fiber. The high isolation between the input and reflected optical power and low insertion loss makes the circulator highly suitable for the use in advanced communication systems and fiber-optical sensor systems.

Besides being highly capable of controlling the light flowing into different directions and directing it into a single desired direction, the insensitive optical circulators have hosts of other qualities that make it much the best choice for fiber optic device. They are:

  • Low insertion loss
  • High isolation
  • Ultra-low PDL and PMD
  • Epoxy-free optical path
  • Special operating wavelengths

The optic circulator provides high reliability and excellent optical performance. The device’s high isolation properties make it ideal for applications in telecommunications, fiber optic sensing, bio-medical, and photonics research.

The circulators com with different ports, for example three or four ports that cover standard wavelength rang. Also, it is possible to customize the wavelength according to different needs. For example, you can get circulators with wavelength ranges such as 1030nm, 1040nm, and 1050nm.

There are various brands making insensitive optical circulators. This means there are a wide range of makes of such optic devices available in the market. They all have features that almost identical but this does not mean they also have the same performance. The process they are built and quality of the material used is factors that play a vital role in the performance of an optic circulator. In addition, other things that should be considered before making the final buying decision are like:

  • Rugged, compact design: Rugged, encased design utilizing bulkhead connectors rather than loose pigtails reduces the fragility of the fibers from tangle and handling.
  • That is easy to install or mount: Choose the one that is easy to mount with optical cables. Four strong magnets hold the rugged package securely onto steel surfaces.
  • Pigtail circulators for the applications that require a length of fiber on the input and output of the circulator.
  • And the price of the circulator

DK Photonics Technology Limited is a leading and one of the top companies providing high quality optical passive components that are widely used for telecommunication fiber sensor and fiber laser applications. If you are looking for quality insensitive optical circulators for the most reasonable price, you can count on DK Photonics Technology Limited.

How does PM Fiber Coupler add value to the multiplexer?

The optical couplers are fused fiber branching devices that split the portion of light allowing optical monitoring. The devices are used extensively in amplifier power control and in transmission equipment for monitoring the performance. The polarization dependent loss coupler is offering low levels of sensitivity to polarization and enables effective management of optical networks. The couplers are available in a wide range of split ratios, lengths and packaging. The Polarization maintaining fused coupler can be bought online for its best usage.

A fused coupler is consisting of two, parallel fibers that can be stretched, twisted, and fused together. The length of the coupling region determines the coupling from one fiber to the other. The Polarization maintaining fused coupler is used to add additional functionality to the network such as network status monitoring. It is the most cost-effective way to minimize the loss and maximize the wavelength isolation. Polarization maintaining fiber coupler is capable of combining two or more inputs into a single output and also divides a single input into two or more outputs.

DK Photonics is the most unique fusing technique that builds the 980/1030/1064nm polarization maintaining fused coupler (PMC). The ratio can be selected according to the requirement and the businesses can benefit a lot buying the fused coupler online.  It features low excess loss, small size and high polarization extinction ratio. The polarization maintaining fused coupler is widely used for optical sensors and amplifiers. A unique fusing technique is used for building the polarization maintaining fused coupler.

How does a fused fiber coupler work?

A fused coupler is consisting of two, parallel optical fibers which are close to each other due to twisting, fusing, and stretching. The length of coupling region determines the coupling ratio from one fiber to the other. Light is launched into the coupling ratio during the manufacturing process and the output power from each output port is carefully monitored. After the achievement of the desired coupling ratio, the fully automated process stops. The process is known as Fused Biconical Taper (FBT) process.

These are the features of Polarization maintaining fused coupler –

  1. It incorporates Low Insertion Loss
  2. It has high extinction ratio
  3. Available in compact In-Line Package
  4. It enables high stability and reliability
  5. It maintains good uniformity with high directivity
  6. Wide variety of wavelengths 780 nm-2005 nm
  7. It is used for fiber optic instruments and fiber sensors
  8. It is also used in research works and enables coherent detection

Polarization maintaining fiber coupler is capable of combining two or more inputs into a single output and also divides a single input into two or more outputs. Make sure that you have the fused coupler for your business or job at the best price and specifications. The coupler are developed using fusing technique and polarization maintaining fiber.

An Essential Guide You Should Consider for Polarization Maintaining Fused Coupler

Do you comprehend what is the optic isolator? This is for you might be a weird idea. Never mind, as a fiber isolator maker from China, we will reveal to you optic isolator works. As the innovation of laser carving has progressed, new markets have advanced to exploit progressively speedier stamping speeds and better checking accuracy and imaging capacities. Proceeding with improvements in laser-depression configuration, shaft directing and centering optics, and PC equipment and programming are extending the part of the frameworks.

  • The two plans furnish the client with a choice of focal points that build up both the measurement of the etching field and the carving line width.
  • Longer-central length focal points give bigger working territories, however, the line width is likewise expanded, along these lines diminishing the power thickness on the work surface.
  • The client must remunerate by either expanding the laser yield control and additionally diminishing the carving speed which generally comprises of two focal points and might be set anyplace in the bar way before the centering focal point.
  • Faraday impact was first seen in 1845 does not have the optically dynamic material in the attractive field by turning the polarization heading of the light happens the substance, otherwise called magneto-optical impacts.
  • For ordinary episode flag light, after the entry to wind up a straightly captivated light from the polarizer, the Faraday pivoting attractive medium, together with the outer attractive field so the right-gave polarization bearing of the flag light 45, and simply make a low misfortune through a polarizer 45 situation of the analyzer.
  • For the turn around the light of the analyzer when a straightly spellbound light through the medium is put, the avoidance heading is correctly pivoted by 45 degrees so the polarization course of the light and the retrogressive bearing opposite to the polarizer, the reflected light is totally blocked transmission.

In the event that you are searching for the best Polarization Maintaining Fused Coupler in China, at that point you ought to associate with the DK Photonics which uses special combining system and polarization keeping up fiber to assemble the 980/1030/1064nm polarization keeping up melded coupler (PMC).The coupling proportion could be chosen by the client’s demand. It includes low abundance misfortune, little size, and high polarization annihilation proportion. PMC is generally utilized for optical sensors and optical gyro.

The PM Fused Coupler can be utilized to part high power straightly energized light in different ways without annoying the line is a condition of polarization (SOP). It can likewise be utilized as a power tap to screen flag control in a PM fiber framework without aggravating the direct SOP of light proliferating in the PM fiber. Applications incorporate PM fiber interferometers, control partaking in polarization touchy frameworks, and flag observing in PM fiber frameworks. Just Contact the DK Photonics and avail the hassle-free service.

All You Should Know About Optical Circulators

A circulator can be identified as an electronic transmitting device made in a ferrous material and intended to help divert a message in a particular direction or destination. A large number of the circulator units accompany various ports, which make it conceivable to guide the signal to the right way. A standard circulator is probably going to incorporate no less than three or four ports. They are usually made to work in conjunction with receivers (antennas), however, there are those transmitters ready to channel microwaves, light, and same signals.

This type of a transmitting device is made to coordinate the flow of electricity as per the energy enters or exists through the ports. A typical style of circulator incorporates three ports which are set at points of 120 degrees separately.

The Optical Circulator

The optical circulator has comparative design and capacity as the optical isolator. It is a nonreciprocal passive device that guides light successively from port 1 to port 2, from port 2 to port 3, and continuously head towards a single direction. The task of a circulator is like that of an isolator aside from the complexity in its construction. Just like a random isolator, optical circulator also uses polarization to carry out its activity.

Several types of circulators are available in the market for commercial use. They have low inclusion loss, high disengagement over a wide wavelength run, polarization dependent loss is low, and low polarization mode scattering.

Typically, the circulator is constructed using Faraday rotators, half-wave plates and a few polaziers.

Polarization Insensitive Optical Circulator – it is practically used for a light with a specific polarization state. The polarization insensitive optical circulator is utilized just as a part of constrained applications, for example, optical sensing and detecting and free-space communications between satellites.

Based on their usefulness, optical circulators can be divided into two categories.

Full circulator: In this, light goes through all ports completing a circle which means light starts from the first port go to the last port and then is always transmitted back to the main/first port. IF we talk about a three-port circulator, light starts from port 1 to port 2, port 2 to port 3, and from port 3 back to port 1.

Quasi-circulator: Here, light goes through all ports in sequence; however, light from the last port is lost and can’t be transmitted back to the primary port. In a quasi three-port circulator, light goes through from port 1 to port 2 and port 2 to port 3, however any light from port 3 is lost and can’t be spread back to port 1. In many applications just a quasi-circulator is required.

Without a circulator, numerous applications must be supplanted by a 3dB fiber coupler which will present 3dB losses. The utilization of circulator provides a similar objective with maintaining less than – 1dB insertion loss.

The Features and Characteristics of Multimode Pump Combiner

The fused multimode Pump Combiners provide very high coupling efficiency over a wide wavelength range from multiple sources to one output fiber. The combiners are offering very high coupling efficiency, high optical power handling, back reflection, low insertion loss and zero-alignment. They ideally used in medical, spectroscopy, sensor, laser, and defense application. The multimode combiners are using the power the power from several multimode laser diodes, with an optional signal feed, into a single, double or triple clad output fiber.

What does it mean to have a multimode pump combiner?

The best combiners mean betting the most of the pump diodes, with minimal heat dissipation management. The combiners are meant to address fiber optic applications used in various markets like research, medical, telecom, and industrial. The processes are capable of high flexibility in the design leading to thousands of different fiber configurations.

Here are the different types of multimode pump combiner –

 

2×1 Multimode Pump Combiner

The pump combiner combines 2 multimode lasers power to create a high power output. It features exceptional optical characteristics and the output fiber is used to transmit energy fiber as the energy synthesis. It provides cost-efficient power transfer for high power applications like direct diode materials processing.

3×1 Multimode Pump Combiner

It combines 3 multimode laser powers to create a high power output. The fiber is transmitting energy as the energy synthesis and it offers efficient power transfer for high power applications. The Multimode Combiners are designed to meet a wide range of power handing configurations and adaption to different fiber types.

4×1 Multimode Pump Combiner

The pump combiner is combining 4 multimode lasers power to create a high power. The combiners have laser power to create exceptional optical characteristics and the output fiber is transmitting energy fiber and pumps cascading enables a maximum conservation of brightness.

7×1 Multimode Pump Combiner

The multimode pump combiner combines 7 multimode laser power to create high power output with consigned fibers. The optical fibers are transmitting energy fiber and the combiner offer efficient power transfer for high power applications.

The multimode combiners feature exceptional optical performance and the device can be used to combine the power from several multimode laser diodes with an optional signal feed. The high power package enables the achievement of power levels in a wide variety of fiber configurations. The fiber allows the optimization of designs and minimizes the transmission loss.

The Features and Characteristics of Optically Fused Couplers

An optically fused coupler is an optical device that is capable of connecting one or more fiber ends in order to allow transmission of light waves in multiple paths. The device combines two or more inputs into a single output and also divides a single input into two or more outputs. The couplers are broadly classified into active and passive devices. The signals are attenuated by fiber optic couplers and input signals can be divided amongst the output ports.

How does the optically fused works?

The fused coupler is a common technology and if the claddings of two or more fibers are partially removed then it is placed in close proximity over some length. It results in the coupling of lights from one fiber to the other. The fraction that couples gets controlled by the thickness of the remaining cladding and the length of the region where the fibers are in proximity.

The couplers are made taking a group of fibers with the cladding exposed and heating the junction. The details of fused fiber coupler operation depend on whether the fibers are multimode or single mode. The degree of coupling depends on length of the coupling zone and does not depend on the wavelength. The light is transferred between the two cores in a resonant interaction that varies in length. As the light enters one fiber, it gets gradually transferred to the other, shifting back and forth cyclically.

There are many benefits of using fiber optic couplers. It has low excess loss, dual operating window, high stability, reliability and low polarization. The couplers have high directivity and low insertion loss. The application use optical couplers like community antenna networks, optical communication systems and fiber-to-home technology.

Here is the list of different optically fused coupler available in the market –

  • 1×2 (2×2) Single Mode Standard Coupler (SSC)
  • 1×2 (2×2) Dual Window Coupler (DWC)
  • 1×2 (2×2) Three-Window Coupler (TWC)
  • 1×2 (2×2) Wide Band Coupler (WBC)
  • 1×2 (2×2) All Band Coupler (ABC)
  • 1×2 (2×2) Mini Size Standard Coupler (MSSSC)
  • 1×2 (2×2) Mini Size Dual Window Coupler (MSDWC)
  • 1×2 (2xN) Single Mode Coupler Module
  • 1×2 (2×2) Mini Size Wide Band Coupler (NSWBC)
  • 1×2 (NxN) Monolithic Single Mode Coupler

The optically fused couplers are used to combine and separate optical signals transmitted on different wavelengths. The intensity profile of the light traveling down a singlemode fiber and the intensity is greatest in the center and tapers off as the core/cladding interface is approached. A waveguide coupler is Y-shaped and it divides input waveguide into two outputs. The fused WDM couplers may be used to add additional functionality to the network like network status monitoring.

The fused WDM couplers are the cost-effective way to minimize a loss and maximize the wavelength isolation. Make sure that the couplers are bought according to the requirement of the business.