Month: May 2013

Sumitomo and Fujikura Fiber Optic Cleavers from FiberStore

Fiber optic fusion splicing is always needed when we want to fuse two optical fibers together for the continuity of fiber optic cable plant. However, in the optical fiber fusion splicing process, fiber tips are required to have a smooth end face that is perpendicular to the fiber axis. Sufficiently perpendicular and planar fiber end face can be achieved via the fiber cleaving process.

Simply speaking, a fiber cleaver is a piece of tools of equipment to make a perfect fiber end face cut that will assure the quality of the joint of bare fibers in the optic fusion process, resulting in lower attention of the fiber connection line.

In the fiber cleaving process, the fiber is pressed against the little cut to force it to break at 90 angle and expose a mirror like fiber end face. The fiber is scratched with a very hard diamond edge scribing tool, which induces a sufficiently large surface crack, then the fiber cleaver applies a tensile stress to the fiber which caused the crack to expand rapidly across the fiber cross section. There are also types of fiber cleaves apply the tensile stress first and then scratch the fiber with the diamond edge scribing tool. A quality fiber cleaver is very essential in determining the fusion splicing loss. This is especially correct for some special fibers including dispersion-compensating fibers and erbium-doped fibers.

A fiber cleave is initiated by lightly scratching the surface of the fiber. When the fiber is thereafter pulled or bent, a crack will originate at the scratch and propagate rapidly across the width of the fiber. This produces a nearly flat cleave of an optical fiber. Under the direction of this idea, there developed a variety of commercial optical fiber cleaving tools in the market:

Some cleavers apply a tensile stress to the fiber while scratching the fiber’s surface with a diamond edge. There are also other designs scratch the fiber surface first, and then apply tensile stress. Some cleaves apply a tensile stress which is uniform across the fiber cross section while others bend the fiber trough a tight radius, producing high tensile stresses on the outside of the bend.

Fiber optic cleaving tool is usually designed for cutting different number of fibers at a time. Single fiber cleaver and ribbon fiber cleaver are typical. They work on the same principles but ribbon cleaver is for simultaneously cleaving all the fibers in a ribbon cable, which is somewhat interior to that of a single fiber cleaver. Most today’s fiber cleavers are suitable for precision cleaving of all common single silica glass fibers. There are also some special cleaver designed ones for applications such as in research, measurement technology and production of optic components.

Under on-side conditions, most high precision cleavers produce a cleave angle deviation within 0.5° with very high reliability and low scattering. Diamond bladed presents the highest cleaver quality and can last over 10,000 cleaves.

It is easy for a modern fiber cleaver to cleave a 125um diameter fiber, but difficult to cleave >200um fibers. This is especially turn when the fiber is not crystalline. Besides, torsion will produce a non perpendicular endface.

Typical brand for fiber optic cleaver are Fujiura, Sumitomo, Furukawa, etc. Typical models of these brand are also available at FiberStore.
Take Sumitomo FC-6S and Fujikura CT-30 for example. The CT-30 cleaver are available fro either single or ribbon fiber splicing applications. It is idea for FTTx applications and equally at home in a splicing van or in a bucked truck. With The 16-position blade yields 48,000 single-fiber cleaves, or 4,000 12-fiber ribbon cleaves beforerequiring replacement, and the built-in scrap collector conveniently stores fiber shardsuntil they can be safely discarded. The FC-6 cleaver is available with a single fiber adapter for 250 to 900 micron coated single fibers. This cleaver is simple for users to operate by removing or installing the single fiber adapter and alternate between mass and single fiber cleaving.

Additional information on a variety of fiber cleaving equipments, please visit FiberStore Fiber Optic Cleavers page or contact our sales team by sales@fiberstore.com.

Working Principle and Characteristics of OTDR

OTDR, the full name of which is Optical Time Domain Reflectometer, is a precise optoelectronic integrated fiber optic test equipment that produced by use of the backscatter during the Rayleigh scattering and Fresnel reflecting in the optical transmission. OTDR tester are widely used for optical cable maintenance and construction, and it can be used for the evaluating the fiber cable length, measuring optical transmission and connection attenuation, detecting the fault location of the fiber links, etc.

During the process of OTDR testing, the instrument inject a higher power laser or fiber optic light source pulse into a fiber from one end of the fiber cable, at the OTDR port to receive the return information. When the optical pulse is transmitted through the fiber, due to the nature of the fiber itself, the connector, the engagement points, bending or other similar event, there will be a scattered reflection. Part of the scattering and reflection will return to the OTDR. Useful information returned will be measured by the OTDR detector, and act as the time or curve segments of fibers at different positions. By recording the time used of the signals from transmission to returning, the transmission speed of the light in the glass fibers, the distance can be calculated.
OTDR testing has some limitation when it come to the applications for measuring the outside able plant loss. The OTDR tester will not be always sufficiently for testing. The OTDR will not work well with short cables in a building or LAN environment. The source and power meter should be used for these tasks as a result of the OTDR is not equipped to show actual cable plant loss.

OTDR use Rayleigh scatting and Fresnel reflection to characterize fibers’ characteristics. Rayleigh scattering refers to the irregular scattering generated when the optical signals transmitting in the fiber. OTDR only measure the scattered light back on the OTDR port. The backscatter signal show the attenuation degree (loss/distance) of the optical fiber, and will be tracked as a downward curve, illustrating the power of backscatter is decreasing, this is because that both transmission signal and backscatter loss are attenuated.

Given the optical parameters, Rayleigh scattering power can be marked, if the wavelength is know, it is proportional with the pulse width of the signal: the longer the pulse width, the stronger backscatter power. Rayleigh scattering power is also related to the wavelength of transmitted signal: the shorter the wavelength, the power is stronger. That is to say, the backscatter loose generated by the trajectory of 1310nm will higher than that of 1550nm signals.

In the higher wavelength region (more than 1500nm), the Rayleigh scattering will continue to decrease, and the other one phenomenon which called infrared attenuation (or absorption) will appear to increase and cause an increase the overall attenuation values. Therefore, 1550nm wavelength is the lowest attenuation, this also explains why it is a long distance communication wavelength. Naturally, these phenomena will return to affect the OTDR. OTDR of 1550nm wavelength is also have low attenuation, so it can be used for long distance testing. While as the high attenuation wavelength 1310nm or 1625nm, OTDR testing distance is bound to be limited, because the test equipment need to test a sharp front in the OTDR trace, and the end of the spikes will quickly fall into the noise area.

Fresnel reflection is discrete reflection, which is caused by the individual point of the whole fibers. These points are caused by a change in reverse coefficient elements such as glass and the air gap. At these points, there will be a strong backscattering light reflected back. Therefore, OTDR is using the information of Fresnel reflection to locate the connection point, fiber optic terminal or breakpoints.

An OTDR tester is essentially an optical radar: it sends out a flash of bright light, and measures the intensity of echo or reflections. This weak signal is averaged to reduce detection noise, and computation is used to display a trace and make a number of mathematical deductions.

Brief Introduction Of Protocol Converter

A protocol converter, referred to as protocol translator, used to convert standard or proprietary protocol of one device to the protocol suitable for the other device or tools to achieve the interoperability, with each protocol based on many factors. It is much like a language translator, translates messages, or data streams, between networks to enable both networks to easily interpret the data. Typical types include E1 to Ethernet, V35 to Ethernet and E1 to V35. Variety protocols used in different fields like Power Generation, Transmission & Distribution, Oil & Gas, Automaton, Utilities, AMR, and Remote Monitoring applications.

Structure Of Protocol Converter
The general architecture of a protocol converter includes an internal master protocol communicating to the external slave devices and the data collected is used to update the internal database of the converter. When the external master requests for data, the internal slave collects data from the database and send it to the external master.

The end result of a protocol converter is to allow the protocol of one machine interact with the protocol of another, increasing the amount of machines the network can use. While the penalties normally are slight, conversion from one protocol to another may slow the connection speed, especially if the converted protocol innately has a lower data rate. Most converters have a database with several protocols, and this database is used to convert the initial protocol to another format.

Different Protocols Of Protocol Converter
The majority of networks have many machines using different protocols, and these protocols dictate how a machine acts. These protocols are determined by several factors, including data rate, encryption methods, file and message formats and associated service, because some services exclusively use one protocol. A protocol converter is tasked with taking this protocol and changing it to another one.

Most protocol converter units are programmed to understand a handful of different protocols, and these units use an internal database to track all the protocols. This database will store all the factors associated with the known protocols, and the database also is tasked with helping this device understand what needs to be changed to alter one protocol to another. Unlike regular databases, which can be manually updated, this database typically is locked from users.

Features Of Protocol Converter
Protocol converters provide physical conversion between ITU-T G.703 standard E1 interface and standard V.35, RS232, RS422 converter, RS485 converter and 10M/100M Ethernet interface, offering security and seamless link for communication between different devices with different interfaces. Protocol supports IEEE 802.3, IEEE 802.1 P, 802.1Q (VLAN). The interface converter transfers data with V.35, RS232, RS485, RS422 output. E1 interface is compatible with ITU-T G.703, G.704 and G.823 supporting BNC 75Ω/unbalance impedance and RJ45 120Ω/balance impedance with speed rates range of 64K~2.048Mbps. Single and multi E1 and framed E1 (FE1) channels; data interface and Ethernet interface; mini rack and 19 inch rack; 220V, 110V, 48V power supply or both are optional, as well as TDM over IP devices.

Protocol converter series may put into action the actual transformation in between single E1 protocol port as well as protocol ports of V.35, V.24, RS232 Ethernet converter or Ethernet within the tranny system; it may be thoroughly utilized in numerous being able to access problems with regard to providers as well as commercial clients, for example DDN, ATM, as well as for that transformation in between router and E1 port, or even the actual occasion exactly where Ethernet tend to be interconnected from divided internet websites through SDH or even additional tranny gear.

A protocol converter usually is helpful. Protocols are software installed on the routers, they are widely used in a variety of industries for applications such as building and process automation. Protocol converters also are used for substation automation, or a system for managing and controlling equipment in an electric power system.

How to Choose A Fiber Optic Connector Polisher

Fiber optic polishing machine has made a big progress since 1990s. Earliest connector termination job are done by manual and labor intensive process, fiber connector polishing was manually done by one single person. With the development of fiber optic network, it requires much more higher efficiency. The fiber optic patch cord manufacturers ever make up it by adding more operators but it still could not catch up with the demand. Until emerge of current automatic polishing machine, fiber connector polishing has meet the requirement of high volume, high quality and consistent.

Quality Fiber Connection Termination is very important for the fiber optic communication system. Fiber optic connector polishing is one of the most important steps for the whole process of terminating fiber connector since bad polished connectors will increase the insertion loss and back reflection which will make you malfunction.

Automatic fiber connector polishing machine are produced according to a set of industry standard and specifications. It can produce large volumes of connectors in a consistent way, and it considered to be cost effective as labor is significantly reduced. Article here is written to help you how to make wise decision when choosing a perfect fiber polishing machine for your specific requirement. Flow the standard mentioned below when purchasing an automatic connector polishing machine.

Polishing Machines with Adjustable Pressure are Preferred

The fiber connector’s finished end-face geometry is generated by the combination of the loading pressure and the hardness of the polishing surface. To optimize the connector end-face, the polishing pressure should be adjustable with clearly marked divisions of measurement.

The four corner hold-downs are also important. Hold-down fasteners in all four corners of the connector holder evenly distribute film pressure to minimize off-center polishing. If you use the center pressure from above, it will allow the possibility of wiggling or vibration the connector holder. By this method, you will increase the vertex offset and leads to inconsistent finishes.

Besides, you should also consider the polishing pad. The polishing pad is conjunction with the four corner hold-downs, is used to distribute the pressures evenly across the polishing area. Since the pads are resilient, they will help to control the radius of curvature as the ferrule is pressed into the pad during the polishing process. There are so many pads for different types of connectors, you should choose the proper one according to your need.

Make sure that you can easily change the holders for different types of connectors

To improve the production output and lower labor cost, you should make sure that you can easily and quickly change different types of connector holders. Typical connector polishing machine should be able to handle most types of fiber connectors such as FC/UPC, SC/UPC, ST/UPC, LC/UPC, MU/UPC, APC, MT-RJ, E2000, SMA905, FA and so on. Besides, the precision of the connector holders are also very critical. The connector holders should be machined to exacting tolerances so that ferrules can be precisely posited for the polishing work.

Removable polishing platens are necessary for the machine

Make sure that the polishing platens can be removable, so that it can not be easily contaminated and its working life will prolong. The polishing platens are the mechanical part that holds the polishing films and polish against the connector end-face.

The polishing motion pattern should be optimized for consistent result while conserving polishing films

As we know, the polishing motion is very critical factor in determining connector’s end-face quality. Polishing motion is the surface which performing the polishing job with the connector. The motion must perform a evenly balanced pressure across all sides, otherwise, the connector will surfer deformed end-face geometry.

Choose the manufacture who can fit for your custom requirement

A qualified manufacturer should have the ability to fit for your different specifications for the polishing film types, timer settings, lubrication and connector holders. Besides, an industry standard compliance test report from the manufacturer can be an important criterion to evaluate a good fiber polishing supplier. It is always a best idea to compare at least 3 different models from 3 vendors so you can choose the best one that meets your particular requirement.

FiberStore is specializes in supplying a full range of fiber optic testing, fiber optic splicing, fiber optic cleaning, fiber optic polishing and fiber optic inspection equipments and tools. Contact us for more detail information.

Fiber Optic Connector Adapter As My Know

Fiber optic adapter or fiber optic coupler is a medium component, designed to connect two fiber optic cables together. A fiber-optic adapter allows fiber-optic cables to be attached to each other singly or in a large network, allowing many devices to communicate at once. Adapters come in versions to connect single fibers together (simplex), two fibers together (duplex), or sometimes four fibers together (quad). Optical adapters are widely uses in light distribution frame(ODF), the optical fiber communications equipment, the measuring appliance and so on.

Fiber Optic Adapter Specifications:
Insertion Loss Durability Operating Temperature: -40 to + 80°C;
Low insertion loss and back reflection loss;
High precision alignment;
Telcordia, ANSI, TIA/EIA, NTT and JIS compliance.

The fiber optic adapters are many types because of the diversity of the connectors. The fiber optic adapters are available in simplex, duplex and quad (for some types like LC and MU) configurations and with FC, SC, ST, LC, MT-RJ, MU, and more types, type MT-RJ is for use with fiber modem applications. According to the fiber connector types that the adapters used to connect there are standard fiber optic adapter and hybrid fiber optic adapter. Besides, there are also bare fiber optic adapter used to connect with the bare optical fibers directly.

Standard Fiber Optic Adapter
Standard fiber optic adapters are simplex, duplex and quad (for some types like LC and MU) structures, they are female to female type, used to link fiber optic connectors, typically they are with ceramic sleeves, fit for both single mode and multimode fiber optic connections.

Hybrid Fiber Optic Adapter
Fiber optic adapters are typically connecting cables with similiar connectors (SC to SC, LC to LC, etc.). Some adapters, called “hybrid”, accept different types of connectors (ST to SC, LC to SC, etc.). A hybrid connector can be designed to fit any two types of fiber-optic cables together. When the connectors have differing ferrule sizes (1.25mm to 2.5mm), as found in LC to SC adapters, the adapters are significantly more expensive because of a more complicated design/manufacturing process.

Fiber optic adapter are used in fiber optic connection, the typical use is to provide a cable to cable fiber connection. Connecting two cables together can allow two devices to communicate from a distance through a direct connection with the fiber-optic line. These simple types of adapters are often referred to as mating sleeves because they allow two cables to connect to one another. Some of these common line to line connectors are also built to connect three or four cables together.

Fiber optic connectors are available in many different models. Each model works with a specific type of fiber optic cable. This makes it even more important for the user to be sure of the type of fiber optic cable he/she is working with in order to make a compatible connection. Fiber optic cables must also be installed properly to ensure that fiber optic cores line up with each other and allow light to pass through them.

Fiberstore offers a wide selection of connector adapter, including FC, SC, ST, LC, MT-RJ, MU, simplex, E2000, FC/APC,duplex, SC/APC, LC/APC, E2000/APC ,quad, mating sleeves, hybrid fiber optic adapters, single mode fiber optic adapters and multimode fiber optic adapters.