Parsing Fiber Optic Connectors

The network cabling industry’s fiber optic manufacturers over the last few decades have been on a constant mission to develop the better fiber connector. This means lower cost, lower dB losses, easier to terminate out in the field. There have been over 100 connectors developed over the years but a select few have stood the test of time and beat out their competition. Now, let’s talk about the most common fiber connectors as following:

A fiber optic connector terminates at the end of a fiber optic cable is used when you need a means to connect and disconnect the fiber cable quickly. A fiber splice would be used in a more permanent application. the connectors provide a mechanical connection for the two fiber cables and align both cores precisely so the light can pass through with little loss. There are many different types of connectors but many share similar features. Many connectors are spring loaded. This will push the fiber ends very close other so as to eliminate airspace between them, which would result in higher dB losses.

There are generally five main components to a fiber connector: the ferrule, the body, the coupling structure, the boot and the dust cap.

Ferrule: The ferrule is the small round cylinder that actually makes contact with the glass and holds it in place. These are commonly made of ceramic today but also are made of metal and plastic.

Body: This sub assembly holds the ferrule in place. It then fits into the connector housing.

Connector Housing: This holds all sub assembly parts in place and has the coupling that will connect to the customer’s equipment. The securing mechanism is usually bayonet, snap-in or screw on type.

Boot: This will cover the transition from the connector to the fiber optic cable. Provides stress relief.

Dust Cap: Just as it implies will protect the connector from accumulating dust.

There are many types of connectors on the market. The major differences are the dimensions and the method of connection to equipment. Most companies will settle on one type of connector and keep that as a standard across the board. It makes sense because all equipment has to be ordered with that specific connector type and to have 2 or 3 different connector types can get messy. For typical network cabling projects today LC is fast becoming the shining star of fiber connectors. LC is a small form factor connector which means it requires a much smaller footprint in your IT closet. Thus you can fit many more LC connectors into you fiber panels then say ST or SC connectors.

LC Connector

The LC connector was developed by Lucent Technologies, hence the LC. It is a Single Form Factor Connector that has a 1.25mm ferrule. The attaching mechanism is similar to an RJ-45 connector with the retaining clip. It is a smaller square connector, similar to the SC. LC connectors are often held together with a duplex plastic retainer. They are also very common in single mode fiber applications.

ST Connector

The ST connector was the first popular connector type to be used as a standard for many organizations in their fiber network applications. It has first developed by AT&T. Often called the “round connector” it has a spring loaded twist bayonet mount with a 2.5mm round ferrule and a round body. The ST connector is fast being replaced with the smaller, denser SFF connectors.

SC Connector

The SC connector is a push in/pull-out type connector that also has a 2.5 mm ferrule. It is very popular for its excellent performance record. The SC connector was standardized in TIA-568-A, and has been very popular for the last 15 years or so. It took a while to surpass the ST because of price and the fact that users were comfortable with the ST. Now it’s much more competitive with pricing and it is very easy install, only requiring a push in and pull out connection. This is very helpful in tight spaces. Simplex and duplex SC connectors are available. The SC was developed by the Japanese and some say stands for Standard Connector.

FC Connector

The FC connector you may find in older single mode installations. It was a popular choice that has been replaced by mostly ST or SC type connectors. It also has a 2.5mm ferrule. They have a screw on retaining mechanism but you need to be sure the key and slot on the connector are aligned correctly. FC connectors can also be mated to ST & SC’s through the use of an adaptor.

MT-RJ Connector

MTRJ stands for Mechanical-Transfer Registered Jack and was developed by Amp/Tyco and Corning. MTRJ is very similar to an RJ type modular plug. The connector is always found in duplex form. The body assembly of the connector is usually made from plastic and clips and locks into place. There are small pins present that guide the fiber for correct alignment. MTRJ’s also are available in male or female orientation. They are only used for multi-mode applications. They can also be difficult to test because many testers on the market do not accept a direct connection. You usually need to rig up a patch cord adaptor kit to make testing possible.

MU Connector

MU looks a miniature SC with a 1.25 mm ferrule. It’s more popular in Japan.

MT Connector

MT is a 12 fiber connector for ribbon cable. It’s main use is for preterminated cable assemblies and cabling systems. Here is a 12 fiber MT broken out into 12 STs.

MT connector is sometimes called a MTP or MPO connector which are commercial names.

Hopefully this guide may help you get an idea of what options are out there for your fiber optic connector needs.

As the best Chinese fiber optic products supplier, FiberStore Inc. supply a range of fiber connectors, fiber attenuatorsfiber optic switch and more. If you would like to know more about our products information, please pay attention our news or contact us directly.

What is The Category 7 Cable

A Category 7 cable (cat 7 cable) is a type of shielded twisted pair cable used in high-speed Ethernet based computer networks of 1 Gbps or higher. It is defined and specified in the ISO/IEC 11801:2002, Class F specification. The Cat 7 cable is backward compatible with Cat 6, Cat 5/e cabling standard and equipments.

The Cat 7 cable is similar to the Cat 6 cable. Each has the same four-pair of twisted cables that support 10 Gbps Ethernet networks and stretch to 100 meters in length. It can provide a bandwidth speed of 600 MHz.

The Cat 7 cable provides more enhanced performance against crosstalk and attenuation than its previous peers by requiring that each pair be completely shielded and form a screen-shielded twisted pair (SSTP) or screen-foiled twisted pair (SFTP) based cabling. It is used in Gb Ethernet and 10 Gb Ethernet networks.

Cat 7 cable is commonly terminated using a GG45 connector, which is a connector that it backwards compatible with the 8p8c RJ45 connectors used on Cat6 or Cat5e cable. The GG45 connector has four additional conductors that provide support for frequencies of up to 600MHz, and up to 1000MHz using Cat7a. The higher frequencies allow Cat 7 cable to support 10-Gigabit Ethernet. Cat7 cable may also be terminated using TERA connectors, which were developed by Siemon. The TERA connector has a unique footprint and is not compatible with a standard 8p8c (RJ45) connector. The TERA connector is also capable of supporting frequencies of up to 600MHz using Cat7a cable. The ability to support the higher frequencies allows Cat7 and Cat7a cable to carry more data. This allows Cat7 and Cat7a cable to support Ethernet applications up to 10-Gigabit Ethernet.

What is the application for a data center?

Cat7 and Cat7a cabling will be used for backbone connections between servers within a data center. This provides a high-speed interconnect used for data transfer within the network.

Does this replace fiber?

This provides an alternative to using fiber optic cabling within the data center. Cat7 and Cat7a cabling will provide similar performance to some fiber solutions. The cost of equipment that supports copper cabling is typically less than equipment that supports fiber cabling. Another advantage is that the copper cabling is not as fragile as fiber cabling.

What’s the practical performance difference with Cat5e/6?

Cat7 and Cat7a cable are designed to support much higher frequency signals than Cat5e and Cat6. This allows Cat7 and Cat7a cabling to carry a larger amount of information. Cat7 and Cat7a cable are also able to better protect the signals traveling over the cable. The shielding as well as the tighter twists of the pairs in Cat7 and Cat7a cable lessens the effects of crosstalk and EMI.

Currently, Cat7 is not widely adopted. Cat5e and Cat6 solutions sufficiently support the bandwidth requirements of today’s data centers, networks, and end users. Using Cat7 for a connection to a desktop would be unnecessary because the bandwidth would not be utilized. It may also be an unnecessary expense for many data center applications for the same reason. However, as technology advances and requirements increase, Cat7 cable will become more relevant in the data center and desktop connections.

As the best fiber optic products supplier, FiberStore Inc. offer Cat7 twisted pair cables, Cat7 Patch Cable, Cat 7 Ethernet cables, if you would like to know our Cat 7 cable price please contact us or visit our website. We also supply other fiber optic products, such as fiber transceiverfiber attenuators, MPO connector and more. Welcome to contact us.

What is Optical Fiber Attenuators

An optical attenuator is a passive device that is used to reduce the power level of an optical signal. The attenuator circuit will allow a known source of power to be reduced by a predetermined factor, which is usually expressed as decibels. Fiber attenuators are generally used in single mode long-haul applications to prevent optical overload at the receiver.

Fiber Optical Attenuators typically come in two forms of packaging. The bulkhead optical attenuator can be plugged into the receiver receptacle. The inline attenuator resembles a patch cord and is typically used between the patch panel and the receiver.

The Principles of Optical Attenuators

Optical attenuators use several different principles in order to accomplish the desired power reduction. Fiber attenuators may use the gap-loss, absorptive, or reflective technique to achieve 
the desired signal loss. The types of attenuators generally used are fixed, stepwise variable, and continuously variable.

Gap-Loss Principle

The principle of gap-loss is used in optical attenuators to reduce the optical power level by inserting the device in the fiber path using an in-line configuration. Gap-loss attenuators are used to prevent the saturation of receiver and are placed close to the transmitter. Gap-loss attenuators use a longitudinal gap between two optical fibers so that the optical signal passed from one optical fiber to another is attenuated. This principle allows the light from the transmitting optical fiber to spread out as it leaves the optical fiber. When the light gets to the receiving optical fiber, some of the light will be lost in the cladding because of gap and the spreading that has occurred.

The gap-loss attenuator will only induce an accurate reduction of power when placed directly after the transmitter. These attenuators are very sensitive to modal distribution ahead of the 
transmitter, which is another reason for keeping the device close to the transmitter to keep the loss at the desired level. The farther away the gap-loss attenuator is placed from the transmitter, the less effective the attenuator is, and the desired loss will not be obtained. To attenuate a signal farther down the fiber path, an optical attenuator using absorptive or reflective techniques should be used.

Keep in mind that the air gap will produce a Fresnel reflection, which could cause a problem for the transmitter.

Absorptive Principle

The absorptive principle, or absorption, accounts for a percentage of power loss in optical fiber. This loss is realized because of imperfections in the optical fiber that absorb optical energy and convert it to heat. This principle can be employed in the design of an optical attenuator to insert a known reduction of power.

The absorptive principle uses the material in the optical path to absorb optical energy. The principle is simple, but can be an effective way to reduce the power being transmitted and received.

Reflective principle

The reflective principle, or scattering, accounts for the majority of power loss in optical fiber and again is due to imperfections in the optical fiber, which in this case cause the signal to scatter. The scattered light causes interference in the optical fiber, thereby reducing the amount of transmitted and received light. This principle can be employed in the planned attenuation of a signal. The material used in the attenuator is manufactured to reflect a known quantity of the signal, thus allowing only the desired portion of the signal to be propagated.

Now that we have looked at the principles behind the attenuator theories, we will discuss some of the types of fiber attenuators. We will examine fixed, stepwise variable, and continuously variable attenuators and when they should be used.

Types of Attenuators

Fixed attenuators are designed to have an unchanging level of attenuation. They can theoretically be designed to provide any amount of attenuation that is desired. The output signal is
attenuated relative to the input signal. Fixed attenuators are typically used for single-mode applications.

Stepwise variable attenuators

A stepwise variable attenuator is a device that changes the attenuation of the signal in known steps such as 0.1dB, 0.5dB, or 1dB. The stepwise attenuator may be used in applications dealing with multiple optical power sources—for example, if there are three inputs available, there may be a need to attenuate the signal at a different level for each of the inputs.

Conversely, the stepwise attenuator may also be used in situations where the input signal is steady, yet the output requirements change depending on the device that the signal is output to.

The stepwise attenuator should be used in applications where the inputs, outputs, and operational configurations are known.

Continuously variable attenuator

Continuously variable attenuator is an attenuator that can be changed on demand. These attenuators generally have a device in place that allows the attenuation of the signal to change as required. A continuously variable attenuator is used in uncontrolled environments where the input characteristics and output needs continually change. This allows the operator to adjust the 
attenuator to accommodate the changes required quickly and precisely without any interruption to the circuit.

Calculating the attenuation value

In summary, there are many types of attenuators and many principles on which they work. The key to choosing the appropriate one is to understand the theory on which each operates and the application that the attenuator will be applied to. Of course, you also need to be able to determine the attenuator value in decibels required for your application.

In this example let’s assume that the maximum optical input power a fiber optic receiver can operate with is -6dBm. If the input power exceeds this power level, the receiver will be overloaded. The transmitter, which is located 10km from the receiver, has an output power of 3dBm. The loss for the 10km of optical fiber, including interconnections, is 5dB.

To calculate the minimum attenuation required to prevent the receiver from being overloaded, we need to subtract all the known losses from the output power of the transmitter as shown here:

Transmitter power (TP) = 3dBm
Receiver maximum optical input power (MP) = –6dBm
Total losses (TL) = 5dB
Minimum attenuation required = MP + TL – TP–6dBm + 5dB – 3dBm = –4dB

At a minimum, a 4dB attenuator is required. However, an attenuator with a larger value could be used as long as it did not over-attenuate the signal.

As the best Chinese fiber optic products supplier, FiberStore Inc. supply a range of fiber attenuators, fiber transceiver, plc splitter, optical fiber sale and more. If you would like to 
purchase our products, please contact us.

Buy Bare Fiber PLC Splitter From FiberStore

Bare fiber PLC splitter is an optical power management device which is widely used in PON networks to realize optical signal power splitting. The common configurations are 1×4, 1×8, 1×16, 1×32 and 1×64 PLC Splitters, but 2×4, 2×8, 2×16, 2×32 configurations are also available. Bare Fiber PLC Splitter comes with unterminated ends so that it can be fused by customers themselves.

Planar Lightwave Circuit (PLC) splitter, PLC splitters are used to distribute or combine optical signals. It is based on planar lightwave circuit technology and provides a low cost light distribution solution with small form factor and high reliability. 1xN PLC splitters are precision aligning process to divide a single optical input(s) into multiple optical outputs uniformly,while 2xN PLC splitters divide a dual optical input(s) into multiple optical outputs. FiberStore PLC splitters offer superior optical performance, high stability and high reliability to meet various application requirements.

The bare PLC splitters are used for small spaces that can be easily placed in a formal joint boxes and splice closure. In order to facilitate welding, it does not need specially designed for space reserved.

FiberStore provides a various of 1xN and 2xN PLC bare splitters, including 1×2, 1×4, 1×8, 1×16,1×32, 1×64 bare fiber type PLC splitter and 2×2, 2×4, 2×8, 2×16, 2×32 bare fiber type PLC splitters.

Bare Fiber Type PLC Splitter Features
  • Good uniformity and low insertion loss
  • Low Polarization Dependent Loss
  • Excellent Mechanical
  • Stability Telecordia GR-1221 and GR-1209
  • Components through TLC-Certified,Conform to YD1117-2001
  • Operating environment: -40ºC to +85ºC
  • High Polarization Extinction Ratio & Excellent Uniformity
  • Fiber input: 0.9um loose tube or 250um bare fiber for choice
  • Fiber output: 250um bare fiber (It is benefit for splicing)
Bare Fiber Type PLC Splitter Applications
  • Fiber to the point (FTTX)
  • Fiber to the home (FTTH)
  • Passive optical networks(PON, GEPON)
  • Local area networks (LAN)
  • Cable television (CATV)
  • Test equipment
Mechanical Drawing

Kind note: This price is without connector

V.S FBT Coupler, the advantages of PLC are as follows
  • The loss to different wavelength transmission is not sensitive, so it can meet the transmission requirements of different wavelength
  • High spectral uniformity, can splitter the signals on average
  • Compact structure, small volume
  • The cost advantage is very obvious on many splitter channels
Order Information

FiberStore provides a whole series of 1xN and 2xN splitters that are tailored for specific applications:

a.1×2, 1×4, 1×8, 1×16,1×32, 1×64, 2×2, 2×4, 2×8, 2×16, 2×32 Versions of splitters are available.

b. SC/UPC, FC/UPC, LC/UPC, SC/APC, FC/APC, LC/APC connectors or no connectors can be selected as you like

c. 250um bare fiber or 0.9 mm loose tube can be choose as input fiber type, 250um bare fiber for output fiber type.

d. The length of pigtail can be also customized; usually we will provide you 1.5m, welcome to contact us for more details.

Sample Pictures


FiberStore also supply other fiber optic products, such as mpo connectorfiber attenuators, Ethernet to fibre optic converter and more. If you would like to purchase our plc splitters, please contact us.

How To Choose Fiber Optic Attenuators

Fiber attenuators are used in fiber optic communications to reduce optical fiber power at a certain level. Why do we need fiber attenuators? Bigger is better, right? Or so most people believe. Beginners in fiber optic technology are often confued with why optical attenuators are necessary to reduce light intensity. Aren’t we using amplifiers to increase the signal power level?

The truth is that too much light can overload a fiber optic receiver. Optical fiber attenuators are needed when a transmitter delivers too much light, such as when a transmitter is very close to the receiver.

How Does a Fiber Attenuator Work?

Optical Attenuators usually works by absorbing the light, such as a neutral density thin file filter. Or by scattering the light such as an air gap. They should not reflect the light since that could cause unwanted back reflection in the fiber system.

Another type of attenuator utilizes a length of high-loss optical fiber, that operates upon its input optical signal power level in such a way that its output signal power level is less than the input level. The power reduction are done by such means as absorption, reflection, diffusion, scattering, deflection, diffraction, and dispersion, etc.

What is the Most Important Feature Should a Fiber Attenuator Have?

The most important spec of an attenuator is its attenuation versus wavelength curve. Optical attenuators should have the same effect on all wavelengths used in the fiber system or at least as flat as possible. For example, a 3dB attenuator at 1500nm should also reduce the intensity of light at 1550nm by 3dB or as close as possible, this is especially true in a WDM (Wavelength Division Multiplexing) system.

Different Types of Attenuators

There are two functional types of fiber attenuators: plug style (including bulkhead) and in-line. A plug style attenuator is employed as a male-female connector where attenuation occurs inside the device, that is, on the light path from one ferrule to another. The types of fiber optic attenuators are based on the types of connectors and attenuation level. FiberStore supply a lot of fiber optic attenuators, like FC, SC/APC, ST, PC, LC, UPC, MU, FC/APC, SC, LC/APC, fixed value plug type fiber attenuators with different attenuation level, from 1dB to 30dB. An in-line attenuator is connected to a transmission fiber by splicing its two pigtails.

The principle of operation of attenuators are markedly different because they use various phenomena to decrease the power of the propagating light. The simplest means is to bend a fiber. Coil a patch cable several times around a pencil while measuring the attenuation with a power meter, then tape this coil. Then you got a primitive but working attenuator. Most fiber attenuators have fixed values that are specified in decibels (dB). They are called fiber optic fixed attenuator. For example, a -3dB attenuator should reduce intensity of the output by 3dB.

Manufacturers use various types of light-absorbing material to achieve well-controlled and stable attenuation. For example, a fiber doped with a transition metal that absorbs light in a predictable way and disperses absorbed energy as a heat. Variable fiber optic attenuators also are available, but they usually are precision instruments used in making measurements.

As the very best China fiber optic products supplier, FiberStore Inc. provides lots of this sort of products which are reliable and economical. If you may well not find it on our website, you can call us to customize it to suit your needs. We also supply PLC splitter, fiber transceiver, optical cable, if you would like to know how much does fiber optic cable cost, please visit our website.