High Density Fiber Optic Array Precision Polishing

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High density fiber optic array polishing to tightest optical specifications with fiber-end surface finish to a few manometers Ra, is now offered as a service to fiber optic array manufacturers.
For applications including: Fiber optics, fiber optic arrays, waveguides, optical switches, WSXC (Wavelength Selective Cross-connects), matrix optical switches, transparent optical cross-connect switches, precision polished NxN switches, MEMS (Micro Electromechanical Systems) devices. As a stand-alone device, fused arrays offer very high coupling efficiency, high chemical resistance and high damage threshold. Coupled to one or more other fibers, the fused arrays become highly efficient fiber beamsplitters and fiber beam combiners.
Ensuring top performance of fiber optic high density arrays, presents many challenges to manufacturers of these devices, particularly in the assembly and polishing operations. Tens, hundreds or even thousands of optical fibers must be assembled with positioning tolerances within several microns. These fibers, each consisting of a 5 to 10 micron core with cladding and coating surrounding it, must then be molded together, terminating into a planar surface. The ends of these fibers must then be polished to near perfection, with flatness within a few microns from edge to edge, and very high quality optical surface finishes to < 5 angstroms. Surface finish and flatness are critical in order to maintain signal integrity and minimize loss. Traditional optical polishing techniques cannot achieve these high-performance specifications.
After extensive R&D efforts, Valley Design has developed the process and equipment fixturing required to provide these services. Valley has closely collaborated with several customers to provide prototype to production high quality polishing of fiber optic arrays.
Application For Optical Switch Polishing
Matrix optical switches, also called NxN switches, allow any input channel to be switched to any output channel. The primary objective is to enable transparent optical cross-connects where the applied signal will remain in the optical mode, and not require optical to electronic to optical conversions. For example, 64 light beams from an 8×8 fiber optic array are intercepted by an 8×8 MEMS-based array of 64 mirrors that move in and out of the beam path. MEMS are tiny mechanical components fabricated by photolithographic technology, typically on a Silicon substrate. These are movable, and in this case, the movable components are mirrors. These fiber optic arrays need to be planarized with a desired flatness of less than 1 micron. The optical fibers themselves also tolerate no imperfections and require a surface finish of only a few nanometers. With over 25 years of polishing experience, Valley can achieve these flatness and surface finish requirements.
These are measured and documented by Valley using our in-house optical interferometers and WYKO instrumentation.
Valley also provides and processes numerous types of substrate materials used for these applications including Fused Silica, Quartz, Pyrex, Glass, GaAs, LiN, InP, Sapphire, Silicon, Ceramics and many others. Valley can lap, polish, dice and edge or angle polish these parts to your specifications. Coating and metallization services are also provided.

The difference between Simplex and Duplex Fiber Optic Cables

When talking about fiber optic patch cable, related products that firstly come to our mind are usually multimode and single mode fiber patch cable.Of course,there are still many other types. But as a beginners in this field might wonder what duplex and simplex fiber patch cables are. This text will introduce you about these cables. Before we come to simplex and duplex fiber patch cables, let’s firstly get familiar with the two words — simplex and duplex.

When talking about fiber optic patch cable, related products that firstly come to our mind are usually multimode and single mode fiber patch cable.Of course,there are still many other types. But as a beginners in this field might wonder what duplex and simplex fiber patch cables are. This text will introduce you about these cables. Before we come to simplex and duplex fiber patch cables, let’s firstly get familiar with the two words — simplex and duplex.

What Do Simplex and Duplex Mean?

According to the ITU-T definition, a simplex circuit is one where signals can flow in only one direction at a time. One end is the transmitter, while the other is the receiver and that is not reversible.

However, at other times, communications can flow in the reverse direction. That is half-duplex. Half-duplex system means a communication channel that operates in one direction at a time and may be reversible. A good analogy for half-duplex system will be two roads with a traffic controller at each end, in order to ensure smooth flow of traffic, the traffic controller only allows one direction at a time. But if one party transmits at the same time, a collision occurs, resulting in lost messages.

“Duplex” comes from “duo” that means “two”, and “plex” refers to “weave” or “fold”. A duplex system has two clearly defined paths with each path providing information in only one direction, that is A to B over one path, B to A over the other. Compared with half-duplex, a full-duplex system, or sometimes called double-duplex allows communication in both directions and allowing this to happen simultaneously. Just like the cellphone, both parties can speak and be heard at the same time.

Simplex Fiber Optic Cable:

Simplex Fiber Optic Cables will be used when a signal only needs to go in one direction. They are designed for production termination where consistency and uniformity are vital for fast and efficient operation.

Simplex Fiber Optic Cable consists of a single fiber,tight-buffered (coated with a 900 micron buffer over the primary buffer coating) with Kevlar (aramid fiber) strength members and jacketed for indoor use, and is used mostly for patch cord and backplane applications. Analog to digital data readouts, interstate highway sensor relays, and automated speed and boundary sensors (for sports applications) are all great uses of Simplex fiber optic cable. This form of fiber cable can be cheaper than Duplex cables, because less material is involved. Simplex Fiber Cable is a single fiber available in single mode, multimode, or polarization maintaining, and they can meet the strength and flexibility required for today’s fiber interconnect applications. We also supply Riser, Plenum rated constructions and LSZH jacket.

Duplex Fiber Optic Cable:

Duplex Fiber Optic Cables consist of two fibers joined by a thin connection between the two jackets. Either single mode or multimode,they are used in applications where data needs to be transferred bi-directionally. One fiber transmits data one direction; the other fiber transmits data in the opposite direction. Larger workstations, switches, servers, and major networking hardware tends to require duplex fiber optic cable.

Duplex fibers types:

Half-duplex: Data may only be transmitted in one direction at a time.

Full-duplex: Data is transferred in two directions simultaneously.

Other duplex infomation:A duplex communication system is a point-to-point system composed of two connected parties or devices that can communicate with one another in both directions, simultaneously. Now, Duplex systems are employed in many communications networks, either to allow for a communication “two-way street” between two connected parties or to provide a “reverse path” for the monitoring and remote adjustment of equipment in the field.

Some Tips To Choice Simplex And Duplex Fiber Cable

When purchasing a fiber optic cable, it is important to understand the different varieties of core characteristics that are available within the cable itself. Each of these different characteristics will have different effects on your ability to transmit information reliably, and these different characteristics also affect the cabling project. You must search the cost of fiber optic cable if you bought the cable. Now, let’s take a look at the most common fiber optic cables.

Simplex Fiber Cable

A simplex fiber cable consists of a single strand of glass of plastic fiber, and is used for applications that only require one-way data transfer. Simplex fiber is most often used where only a single transmit and receive line is required between devices or when a multiplex data signal is used (bi-directional communication over a single fiber). Simplex fiber is available in singlemode and multimode. For example, an interstate trucking scale that sends the weight of the truck to a monitoring station or an oil line monitor that sends data about oil flow to a central location.

Duplex Fiber Cable

A duplex fiber cable consists of two strand fibers of glass or plastic. Typically found in a “zipcord”(side-by-side) construction format, this cable is most often used for duplex communication between devices where a separate transmit and receive are required. Duplex fiber is available in singlemode and multimode. Use multimode duplex fiber optic cable or single mode duplex fiber for applications that require simultaneous, bi-directional data transfer. Workstations, fiber switches and servers, fiber modems, and similar hardware require duplex fiber cable.

Cable Design Criteria For The Pulling Strength,Water Protection,Fiber Code Ratings

Pulling Strength: Some cable is simply laid into cable trays or ditches. So pull strength is not too important. But other cable may be pulled through 2 km or more of conduit. Even with lots of cable lubricant, pulling tension can be high. Most cables get their strength from an agamid fiber, a unique polymer fiber that is very strong but does not stretch – so pulling on it will not stress the other components in the cable. The simplest simplex cable has a pull strength of 100-200 pounds, while outside plant cable may have a specification of over 800 pounds.

Water Protection: Outdoors, every cable must be protected from water or moisture. It starts with a moisture resistant jacket, usually PE (polyethylene), and a filling of water-blocking material. The usual way is to flood the cable with a water-blocking gel. It’s effective but messy – requiring a gel remover. A newer alternative is dry water blocking using a miracle powder – the stuff developed to absorb moisture in disposable diapers. Check with your cable supplier to see if they offer it.

Fire Code Ratings: Every cable installed indoors must meet fire codes. That means the jacket must be rated for fire resistance, with ratings for general use, riser (a vertical cable feeds flames more than horizontal) and plenum (for installation in air-handling areas. Most indoor cables use PVC (polyvinyl chloride) jacketing for fire retardance. In the United States, all premises cables must carry identification and flammability ratings per the NEC (National Electrical Code) paragraph 770.

Conclusion

After reading the above statements, do you have a brief understanding of simplex fiber patch cable and duplex fiber patch cable? When choosing one over the other, the key factor is that the equipment requires one-way or bi-directional data transfer. Fiber-Mart has large numbers of simplex and duplex fiber optic patch cables, such as single mode simplex fiber patch cable, LC to LC duplex single mode patch cable, 10 gigabit multimode duplex cables, LC ST duplex patch cord and so on. I believe you can find a suitable fiber optic patch cable for your devices in Fiber-Mart.please contact us: product@fiber-mart.com.

Why Optical Fiber for the Medical Industry?

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Even though the first use of lasers in medicine was reported by Goldman in 1962-and then in 1963 for experimental cardiovascular plaque ablation-it is the Aesthetic and Ophthalmic applications that historically pushed the use and adoption of photons in medicine. In addition to invasive and non-invasive cosmetic treatments and ophthalmic therapies, urology is another mature market today using lasers and optical fiber probes. In this market lasers and optical fibers are used in transurethral laser therapy for benign prostatic hyperplasia (BPH) and kidney stone ablation.
What are the next big emerging markets? Groups and organizations in the public and private sectors are developing systems that incorporate an optical fiber probe for diagnostic and therapeutic purposes. Many of these applications target disposable probes at high volume procedures. This creates a challenge for device manufacturers and their suppliers to produce, on a repeatable basis, an optical probe requiring crucial complex engineering and control at a price point the market (and insurance companies) can bear. In vivo probes for optical coherence tomography are already on the market. Other examples of emerging applications include: cancer detection; tumor ablation; other soft tissue ablation such as meniscuses; probes for sensing and imaging; and the incorporation of optical fiber in existing medical devices found in MRI suites, radiation suites, and X-Ray suites.

Searching Deep Space via Optical Fiber

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For the first time, researchers have shown that a stable frequency reference can be reliably transmitted for more than 300 kilometers over a standard fiber optic telecommunications network in order to synchronize two radio telescopes.
In The Optical Society of America’s Optica journal, researchers from a consortium of Australian institutions recently reported this successful transmission between two radio telescopes using an optical fiber link. They also demonstrated that the technique’s performance was superior to using an atomic clock at each telescope.
Stable frequency references, used to calibrate clocks and instruments that make ultra-precise measurements, are usually only available at facilities that use expensive atomic clocks to generate the references. This new technology could help scientists anywhere to access the frequency standard by simply tapping into the telecommunications network.
This new technique required no substantial changes to the rest of the fiber optic network and was easy to implement. Most impressively, the demonstration was performed over a fiber optic network that was transmitting live telecommunications traffic at the same time. By running the experiment on optical fibers carrying normal traffic, the researchers showed that transmitting the stable frequency standard did not affect the data or telephone calls on other channels.
To keep the frequency stable during transmission, the researchers sent the signal through the network to a selected destination and then reflected it back. Then, the returning signal was used to determine whether any changes occurred. After each round trip, any frequency shift was subtracted to precisely compensate for the measured changes. For every 100 kilometers of fiber, the round trip for the signal took approximately 1 millisecond.
According to the researchers, the successful demonstration shows that this new method is ready for use by radio astronomers who want to avoid using multiple atomic clocks across a telephone array. This capability would also allow any scientist with access to a telecommunications network to broadcast stable frequency references across a national fiber optic network.
The ability to send stable frequency references over a telecommunications network may be especially useful for radio telescope arrays such as the Square Kilometer Array (SKA).  SKA is a global effort to build the world’s largest telescope using arrays in Australia and South Africa. When completed, SKA will detect faint radio waves from deep space with an approximately 50 times greater sensitivity than that of the Hubble telescope. In addition, individual radio telescopes will be linked to create a total collection area of about 1 million square meters.
The research group hopes that ready access to frequency standards as stable as those in a national measurement laboratory will serve as an enabling technology for many applications that demand precise timing and accurate frequency measurements.

Basic Fiber Optic Cable Tool Kit

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The fiber-mart.com Basic Fiber Optic Tool Kit provides you with dozens of basic tools that are essential for fiber optic termination, splicing, and testing. The kit includes strippers, cable slitters and other precision hand tools, consumable products, and much more. All of the contents are packed in a durable case, keeping the items you need within easy reach. Contents of the entire kit are listed below.
Contents of Fiber Cable Tool Kit
PVC Electrical Tape
3oz. Alcohol Bottle
Fiber Strippers
Connector Cleaner
Kevlar Scissors
Jacket Stripper
Buffer Tube Stripper
Round Cable Slitter
6 Side Cutting Pliers
50 Foam Swabs
Kim Wipes
Utility Knife
Tweezers
Needle Nose Pliers
Piano Wire
4 Bit Screwdriver
Black Marker
Safety Glasses
5 D-Gel Wipes
Black Work Mat
Fiber Disposal Unit
Ruler
Fabric Tape Measure
1/2 Nut Driver
3 Economy Tie Labels
Rugged Carry Case
5 Fusion Splice Sleeves
1Mtr 3mm Furcation
1Mtr 900µm Furcation

How to Use OADM in WDM Network ?

OADM is a cost-effective and easy to use passive fiber optic component, which can provide easy to build and grow connectivity environment for WDM network.

OADM is a cost-effective and easy to use passive fiber optic component, which can provide easy to build and grow connectivity environment for WDM network.Optical add-drop multiplexer is one of the key devices to implement such optical signal processing. Use of OADM makes it possible to freely add or drop signals with arbitrary wavelengths over multiplexed optical signals by assigning a wavelength to each destination.this article ,Let us introduce how to use OADM in WDM Network?

Inside an OADM

A traditional OADM consists of three parts: an optical demultiplexer, an optical multiplexer and between them a method of reconfiguring the paths between the optical demultiplexer, the optical multiplexer and a set of ports for adding and dropping signals. The multiplexer is used to couple two or more wavelengths into the same fiber. Then the reconfiguration can be achieved by a fiber patch panel or by optical switches which direct the wavelengths to the optical multiplexer or to drop ports. The demultiplexer undoes what the multiplexer has done. It separates a multiplicity of wavelengths in a fiber and directs them to many fibers.

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Main Function and Principle of OADM

For an OADM, “Add” refers to the capability of the device to add one or more new wavelength channels to an existing multi-wavelength WDM signal while “drop” refers to drop or remove one or more channels, passing those signals to another network path. The OADM selectively removes (drops) a wavelength from a multiplicity of wavelengths in a fiber, and thus from traffic on the particular channel. It then adds in the same direction of data flow the same wavelength, but with different data content. The main function of OADM function is shown in the following picture. This function is especially used in WDM ring systems as well as in long-haul with drop-add features.

How to Connect OADM With WDM MUX/DEMUX

In most cases, OADM is deployed with CWDM or DWDM MUX/DEMUX. It is usually installed in a fiber optic link between two WDM MUX/DEMUXs. The following picture shows a CWDM network using a 1-channel dual fiber OADM between two CWDM MUX/DEMUXs. Signals over 1470 nm are required to be added to and dropped from the dual fiber link. On the OADM, there are usually one port for input and one port for output. The OADM can be regarded as a length of fiber cable in the fiber link. The point is the one or more strand of signals is added or dropped when the light goes through the OADM.

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Summary

OADM is still evolving, and although these components are relatively small, they are immeasurable in the future.Optical Add-Drop Multiplexer (OADM) is used for multiplexing and routing different channels of fiber into or out of a single fiber. The CWDM OADM is designed to optically add/drop one or multiple CWDM channels into one or two fibers. Fiber-Mart provides a series of OADM modules which can be Customized. For more information, welcome to visit www.fiber-mart.com or contact me by e-mail: service@fiber-mart.com