What is An Optical Time-domain Reflectometer Used for

Optical Time-domain Reflectometer is the full name of OTDR. In fiber tester fields, it is a very important and common optoelectronic instrument used for certifying and characterizing the optical fibers. During its working process, the optical time domain reflectmeter send a series of fiber optic pulses into the fiber cable, the fiber signal light will be scattered back and reflected back from points along the fibers. because of the fiberglass attribute, fiber joint point or fiber break. The strength of the return pulses is measured and integrated as a function of time, and is plotted as a function of fiber length. By this way, the OTDR can detect the fiber optic cable length, fiber optic cable overall attenuation and locate the break point. In the following text, we will introduce the two major function of the optical time domain reflectmeter.

Certifying Fiber Optics
A good quality of fiber optic networks is very important for the healthy of the critical networks especially for business use. For a network administrator, it is very necessary to known how well the invested fiber cabling network performed and how to solve problems at the first time they occur. Fiber optics certification has experienced a development from Tier 1, the Fiber Optics Certification Basic to Tier 2 fiber certification, that extended Tier 1 with an Optical Time Domain Reflectometer (OTDR).

The Tier 1 tests are attenuation (insertion loss), length and polarit, the complete Tier 1 fiber certification is required in all fiber optic cabling links. During the Tier 1 testing, each fiber
link is measured for attenuation and results are documented. This test ensures that the fiber link exhibits less loss than the maximum allowable loss budget for the immediate application. This CertiFiber is one handheld tester that quickly and easily certifies multimode networks. One button measures fiber length and optical loss on two fibers at two wavelengths, computes the optical loss budget, compares the results to the selected industry standard and provides an instant PASS or FAIL indication. By Tier 1 testing, the invisible events are hardly to locate.
Tier2 is the extended Tier 1 with the application of an additional tool, OTDR, which is used to trace each fiber link. An OTDR trace is a graphical signature of a fiber’s attenuation along its
length. You can gain insight into the performance of the link components such as fiber optic cable, connectors and splices and the quality of the installation by examining non-uniformities in the trace. This fiber test certifies that the workmanship and quality of the installation meets the design and warrantee specifications for current and future applications. An obvious advantage of using OTDR is that is helps detect the invisible events that may happened when conducting only loss/length (tier 1) testing, which is regarded as a complete fiber certification.

Maintaining Fiber Infrastructure Performance
Besides fiber optics certification, OTDR is also used for repairing problem fiber plant. Because the OTDR makes you detect any details on the cabling installation, termination quality and offers advanced diagnostics to isolate a point of failure that may hinder network performance.

OTDR tester characterize features such as attenuation uniformity and attenuation rate, segment length, location and insertion loss of connectors and splices, and other events such as sharp bends that may have been incurred during cable installation. The right OTDR must has certain functionality, such as loss-length certification, channel/map view, power meter capabilities, an easy-to-use interface, and smart-remote options.
Fiber optic testing tools manufacturers such as FiberStore, provides the ultimate optical time domain reflectometer series for your testing and troubleshooting solution of fiber optic networks, which includes EXFO AXS-100, EXFO AXS-110-12CD, DVP-321 OTDR, EXFO FTB-200 OTDR and more. They are all perfect for perform inspection, verification, certification, troubleshooting.

Fiber Optic Tools To Terminate Fiber Optic Cables

There are various kinds of fiber optic tools utilized in the fiber optic installation and maintenance works. And the cable stripper is a tool to remove the outside jacket from an optical fiber cable, plays an important role in the fiber optic cable splicing process.

A high quality fiber stripper will safely and efficiently remove the outside jacket from an optical fiber cable. Just with a highly fiber stripper of your fiber cable jacket tends to make an undamaged exposed fiber that is important for successful splicing of two optical fibers. An optical fiber stripper can help you speed up the process of performing fiber network maintenance work and avoid excessive network downtime. But do you know how to cut fiber optic cables?

Terminating fiber optic cables might seem complicated if you do it the first time. Follow these instructions below to understand the proper method of cutting and do the job yourself. Read on to learn the basics of cutting fiber optic cables. Your safety is of utmost importance. Wear gloves while working with fiber optic cables.

With the right set of tools, fiber optic cable cutting can be a very simple undertaking. Striping fiber optic cable isn’t a job for a wire stripper. You need special strippers that allow you to precisely remove the correct cable layers for the job. The tools needed for fiber terminations are fiber optic cable strippers, kevlar scissors, fiber cleavers, ST, SC, LC or MTRJ fiber optic connectors, fiber connector hand polishing puck, fiber polishing films and fiber inspection microscope.

1. Strip the fiber with a fiber optic stripper

Tri-Hole Fiber Optic Stripper
Fiber cables come with 3mm jacket, Kevlar strength member and 0.9mm buffer coating. To get off the 0.125mm fiber cladding, you need to remove the 3mm jacket with a fiber stripper, then cut the Kevlar fibers with a Kevlar cutter, finally strip the 0.9mm buffer down to 0.125mm cladding with a fiber optic stripper.

2. Cleave the fiber with a fiber cleaver

Fujikura CT-30A High Precision Fiber Cleaver
After stripping the fiber down to 0.125mm cladding, you insert the fiber into a SC, ST or LC connector, and then inject some fiber optic epoxy into the connector with a syringe. You will then lay the connector into a hot oven to cure the fiber epoxy so it can hold the fiber tightly. After the curing process, you cleave extra fibers from the connector tip with a Fujikura cleaver.

3. Hand polishing the fiber
In the next step, you put the connector (already with fiber fixed inside) into a hand polishing puck, which serves as a fixture while you polish the end face of the connector to get a high quality mirror like finish. You then hold the polishing puck and polish the connector on a connector lapping film in a figure 8 shape for 10~15 times. Repeat the hand polishing steps stepping from 12um, 3um and 0.5um lapping films.

4. Fiber termination quality inspection
The final step is to inspect the quality of your work. You insert the finished connector into a fiber optic inspection microscope which zooms to 200 to 400 time level to show you all the scratches and pits that may exist on the connector end face. If everything looks perfect, then you can connector your fiber into the network.

Better Knewing Optical Power Measurement

As fiber optic system becomes more and more common and has increasingly sophisticated, optical power measuring, the most basic actions for the fiber optic testing process, will also grow more and more complex. To make reliable measurements, people must consider the characteristics and interactions of optical power meter, fiber optic light source, detector types, attenuation, back
reflection, interference, and beam divergence.

Optical Power Meter Measurement

An optical power meter is used to measure the absolute optical power or the relative length of optical fiber optical power loss. Through the measurement of the absolute power of the transmitting end optical network, a power meter to be able to evaluate the performance of the light end equipment. The basic assumption for optical power measurement is the at the meter output reading is
directly proportional to the optical input power. This proportionality property is defined as linearity, and the departure from this direct proportionality is defined as nonlinearity.

Optical Light Source
Optical measurements can be made with a wide variety of light sources. Fiber optic light sources are designed to cover a variety of wavelength ranges to suit all optical testing needs, Light sources are offered in a variety of types including LED, halogen and laser. With the combination of a power meter and stabilized light source, it is possible to measure the connection loss, test continuity and help evaluate the transmission quality of fiber link. Optical Multimeter jor fiber optic multi meter integrates both an optical power meter module and an optical light source module and can perform closed-loop tests by using both modules, and can also work individually.

Optical metering system
Typical optical power measurement system consists of a detector and a display unit that calculates the optical power or energy represented by the electrical signal. The measurements are displayed or stored in convenient formats, such as analog or digital output, or entries in a data-collection file.
The optical detector, which converts an optical signal into an electrical signal, The most common types of optical-signal detectors are photodiodes, thermopiles, and pyroelectric detectors.
Photodiodes use the photon’s energy to create an electron-hole pair, Thermopile detectors are used for high-power laser sources, up to tens of kilowatts of optical power. Pyroelectric sensors are popular for pulsed laser sources. Among these detector types, photodiode sensors are the most widely used.

Light source back inflection
Accurately measuring a modulated or a pulsed light is very difficult as well as the CW (Light source back inflection) light source. When making peak-to-peak measurements, since waveforms can be greatly distorted. Rather tan reading directly from the detector. It is better to record the raw data, and than process it with digital filtering or statistical averaging with the fact of the limitations of the detector’s response time, and the speed of the meter’s circuitry.

To sum up, optical power measurement involved in the application of optical power meter, a stable fiber optic light source as well as the good understanding of the optical setup, the choice of detector types, detector saturation and noise, attenuation.

CCTV Camera Tester Supplied By Fiberstore

Fiberstore supplies a variety of cctv tests. Our range of quality CCTV Multifunction Testers are a must for every CCTV installer. They are cheap and enable you to set up and test your CCTV installations easily. CCTV testers minimize your commissioning cost and increasing your competitiveness. It’s an excellent helper and partner for the installer in project case.

Fiberstore stocks seven different models of hand-held test monitors, which are ideal devices for installers and field technicians to test video, PTZ functions, and status of UTP cables conveniently and efficiently.

Major Features of CCTV Tester:

LCD Video Monitor PAL or NTSC;

Video Signal Generator;

PTZ Controller for Camera;

PTZ Protocol Tester;

Cat 5 Cable Tester;

Rechargeable Batteries with Charger;

Additional Features (P/N E9010T Only);

IRE Signal Voltage Measurement;

Sunshade/Screen Protector;

7 Color Bar Video Signal Generator;

Multimeter function ( Volts AC, Volts DC and Resistance);

12VDC out for powering camera to make testing easier.

The STest-894 cctv camera tester with multimeter is developed for the On-Site installation and maintenance of video monitoring system. It can be used for displaying video, controlling PTZ, DC12V1A power for camera, Audio input test, generating images, capturing data of RS485 and testing LAN cable etc. Its functions, easy operation, and portability makes it simple for the CCTV technician to install and maintain CCTV system, improving work efficiency and get the labor cost down.

Another featured product in this line is the 7 Inch Industrial Panel PC with WinCE 5.0 featuring standard communication interfaces including Gigabit Ethernet and isolated RS232/RS485 serial ports, which can connect to industrial automation PLC, DCS, SCADA and PAC systems for production and factory automation applications. This family also includes 9 Channel Real Time Color Video Multiplexer which can be widely used in security monitoring, highway monitoring, toll station video surveillance system, industrial closed circuit television surveillance and high quality video conferencing and 4 Channel Color Video Quad Processor which provides high-quality split screen output for real-time multiple video channel display, live monitoring or recording purpose.

CCTV Tester PRO is developed for the installation and maintenance of video monitoring system. It can be used for displaying video, controlling PTZ, generating images, capturing data of RS485 and testing LAN cable etc. Its functions, easy operation, and convenient portability enable it simple for the contractor to install and maintain the video camera, promote working efficiency and cost-down the expenditure of the project.

CCTV Tester Application:

CCTV system installation and maintenance;

All in one camera testing;

The CCTV transmitting channel testing;

PTZ controller;

Lan cable testing.

Fiberstore is a global leader in research, development and manufacturing of high performance telecommunication fiber testers and fiber tools.

Optical Attenuator and Optical Power Meter Calibration

In the fiber optic network systems, that is the true that the power level of an optical signal, either in free space or in an optical fiber are not always the same. For example, for fiber optic receivers, too much light can overload it and degrade the bit error ratio. In order to achieve the best bit error ratio, the light power must be reduced, this time an optical attenuator is need to balance the power of the light by reducing the higher power and fit for the fluent signal transmissions between different devices.

The working principle of the fiber optic attenuator can be compared to a sunglass, which absorbs the extra light energy and protect you eyes from being dazzled. Attenuators typically have a working wavelength range (usually from 1310 to 1550nm) in which they absorb the light energy equally. An important characteristic of a good fiber attenuator is that they should not reflect the light instead, they should absorb the extra light without being damaged. Since the light power used in fiber optic communications are fairly low, they usually can be absorbed without noticeable damage to the attenuator itself.

Fiber optic attenuators are used for reducing the power of the light in the fiber optic network. two types fiber optic attenuators, fixed value fiber optic attenuator refer to the attenuator that can reduce the power of fiber light at a fixed value loss, for example, 2dB. Their applications include telecommunication networks, optical fiber test facility, LAN and CATV systems. Fixed value fiber optic attenuators are composed of four groups: Fixed-Plug in type, fixed adapter Type attenuator, fixed In-line type attenuator, and Fixed Hybrid Adapter type. While adjustable fiber optic attenuator refer to the attenuator that can generate an adjustable Loss to the fiber optic link, they are general used for testing and measurement, but they also have a wide usage in EDFA for equalizing the light power among different channels. Variable Fiber optic attenuators are composed of three groups: Variable plug-in type, Variable adapter type, Variable In-line type and Manual VOA type.

The attenuators can be female to female which is called bulkhead fiber optic attenuator or male to female which is also called a plug fiber optic attenuator. Bulkhead and plug types are designed without cables; another type inline fiber optic attenuator is designed with a piece of fiber optic cable.Wide range variable & inline fiber optic attenuators .the inline fiber optic attenuators are with more accurate attenuation compared with traditional connector type fiber optic attenuators. Variable in-line Optical attenuators are often used with an optical power meter in the optic amplifier systems to balance the gain across the different operating wavelengths.

A wide range of fiber optic attenuators are supplied at ingellen.com which includes LC, SC, and ST, FC, MU, E2000, Fixed Adaptor Type Attenuators, Fixed In Line Type Attenuators, Variable Attenuator Instrument and Variable attenuators. Our fiber optic attenuators are manufactured according to international standard and are compartible with the fiber optic products currently available in the international market.

The optical attenuator is an essential component where optical signal levels need to be adjusted over a wide range of powers. To make the reliable measurements, one must consider the characteristics interactions of fiber optic light source.  Optical light sources are used with the fiber optic power meter to test the fiber system loss, which can offered in a variety of types including LED, halogen and laser. With the optical attenuator and optical power meter calibration system, the attenuation can be easily modified to any level required for telecom and CATV network.