Handbook for Sound Engineers

474 Chapter 15

15.9.4.2 LC Versus Other Types of Fiber Optic
Connectors (ST, SC, etc.)

The LC-type connector over other types of connectors is
made for more consistent performance and reliability.
The benefits of using the LC type connector are:

1. It is square in shape and keyed, allowing for anti-
   rotation, which in turn increases the life expectancy
   of the connector when mated frequently.


2. It provides for quicker access to patch panel appli-
   cations where the ST connector (for example) has
   to be turned to lock.


3. It uses a push-pull insertion release mechanism
   similar to the familiar RJ-45 telephone plug.


4. It allows tightly spaced patch panels, because it
   need not be turned to be engaged or disengaged.


5. The LC is called a small form factor (SFF)
   connector, which is about half the size of the SC
   connector and provides for high-density patch
   panels.


6. It offers better axial load and side pull features than
   the ST connector, thus eliminating disturbances
   caused by the user touching the cable or boot.


7. Users feel comfortable with LC because of its oper-
   ational resemblance to an RJ-45 electrical
   connector.


8. The LC type is universally available throughout the
   world.


9. It eliminates optical discontinuities resulting from
   pulling on the cable.


10. It is cost effective.

NOTE: For manufacturers with a large base of existing
ST or SC type connectors installed, there are hybrid
adapters to mate ST or SC connectors to an LC connec-
tor, or vice versa, if needed.

15.9.4.3 Fiber Optic Connector Termination
Advancements

Fiber connector manufacturers have now improved the
termination process in putting a connector together in a
few easy steps. One such device is made by Corning,
Inc., called the UniCam® connector system. The Uni-
Cam® can be best described as a mini pigtail. It incor-
porates a factory-installed fiber stub that is fully bonded
into the connector’s ferrule. The other end is precisely
cleaved and placed into the patented alignment mecha-
nism of Corning’s mechanical splice. Both the field
fiber and fiber stub are fully protected from environ-
mental factors. Unlike other no-epoxy, field-installable
connectors, the UniCam® connector requires no polish-

ing, which cuts down the time and cost to install and

terminate fiber optic connectors. Now it takes about

1 minute to terminate a fiber optic LC, ST, or SC, which

is much faster than the time to solder an XLR audio

connector. Fig.15-34 shows a UniCam® connector sys-

tem tool.

15.9.4.4 Fiber Optic Splices

A splice is two fibers joined in a permanent fashion by

fusion, welding, chemical bonding, or mechanical join-

ing. The three main concerns in a splice are:

1. Splicing loss.


2. Physical durability of the splice.


3. Simplicity of making the splice.

The losses in a fiber optic splice are the same as for

FOCs, intrinsic and extrinsic. However the tolerances

for a splice are much tighter; therefore, lower attenua-

tion figures are produced.

There are far too many splicing types available to

mention; therefore, the following discussion is on

splices useful for audio applications. One type by

Lucent is called the CSL LightSplice System. It provides

a fast, easy cleave/mechanical splice for permanent and

restoration splicing of single mode and multimode

fibers. The CSL LightSplice System features low loss

Figure 15-34. UniCam connector system. Courtesy of

Corning, Inc.