Appeal No. 2005-1942 Page 10
Application No. 10/173,938
2a may have a positive dispersion (D+) characteristic
and optical fiber 3a may have a negative dispersion (D-)
characteristic. While traveling through a D+ optical
fiber, an optical pulse signal stretches, thereby
increasing its duration compared with the original
optical signal. On the other hand, while traveling
through a D- optical fiber, the optical pulse is
shortened, thereby decreasing its duration compared
with the original optical signal. Thus, by optically
connecting suitable lengths of D+ and D- optical fibers
the net dispersion of a DMN can be manipulated to have a
relatively low net dispersion.
However, a direct optical connection between optical
fibers having extremely different first and second
dispersion characteristics can undesirably result in a
relatively high splice loss. For example, directly
connecting D+ and D- optical fibers having MFDs of about
11.5:m and 6.0:m, respectively, results in a relatively high
splice loss. To overcome this relatively high splice loss,
the DMNs of the present invention optically connect D+ and
D- optical fibers in a fiber optic cable closure with bridge
fiber 42 there between. In one embodiment, the bridge fiber
acts as gradual change in MFD between the D+ and D- optical
fibers, thereby allowing for a relatively low splice loss.
Even though bridge fiber 42 has different optical
characteristics than either the D+ and D- optical fibers,
the splice loss is advantageously reduced compared with a
direct D+ to D-splice.
From this disclosure, and the lack of any support provided
by the examiner to support the examiner’s position, we find that
an artisan would have considered a bridge fiber to be an optical
fiber which connects fibers of different dispersion
characteristics than the bridge fiber, and not merely “an optical
fiber which connects two elements” as asserted by the examiner.
In addition, we observe the disclosure of Mukasa (col. 5, lines
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