3-9
Reference
Fiber-Optic Connectors
tions take repeatability uncertainty into account?
•Will a connector degrade the return loss too much, or will a fusion splice be re-
quired? For example, many DFB lasers canno t operate with reflections from
connectors. Often as much as 90 dB isolation is needed.
Figure3-1. Basic components of a connector.
Over the last few years, the FC/PC style connector has emerged as th e most
popular connector for fiber-optic applications. While not the highest perform-
ing connector, it represents a good compromise between performance, reli-
ability, and cost. If properly maintained and cleaned, this connector can
withstand many repeated connections.
However, many instrument specifications require tighter tole rances than most
connectors, including the FC/PC style, can deliver. These instruments cannot
tolerate connectors with the large non-concentricities of the fiber common
with ceramic style ferrules. When tighter alignment is requ ired, Agilent
Technologiesinstruments typically use a connector such as the Diamond
HMS-10, which has concentric tolerances within a few tenths of a micron. Agi-
lent Technologies then uses a special universal adapter, which allows other
cable types to mate with this precision co nnector. See Figure 3-2.