91影视

• Fiber optics, often known as optical fibre, is a technology that uses light pulses to convey data along a glass or plastic fibre.
• A fibre optic cable can have anywhere from a few to several hundred of these glass fibres.
• The glass fibre core is surrounded by another glass layer called cladding.

(a)

For entire reflection, the minimal angle ${\mathrm{胃}}_{\mathrm{i}}$is

${\mathrm{蝉颈苍胃}}_{\mathrm{i}}=\frac{{\mathrm{n}}_{\mathrm{cladding}}}{{\mathrm{n}}_{\mathrm{core}}}$

Simplify fortheminimum angle${\mathrm{胃}}_{\mathrm{i}}$for total reflection in the optical fiber in 1.600.

For${\mathrm{n}}_{\mathrm{core}}=1.6$,the${\mathrm{胃}}_{\mathrm{i}}$is:

$$\begin{gathered} {\mathrm{蝉颈苍胃}}_{\mathrm{i}}=\frac{1.4}{1.6} \\ {\mathrm{蝉颈苍胃}}_{\mathrm{i}}=0.875 \\ {\mathrm{胃}}_{\mathrm{i}}=61.04掳 \end{gathered}$$

The entire reflection in an optical fibre, the minimum angle ${\mathrm{胃}}_{\mathrm{i}}$is $\mathrm{胃颈}鈮�61.04掳$

(b)

Simplify forthe minimum angle ${\mathrm{胃}}_{\mathrm{i}}$for total reflection in the optical fiber in 1.800

For ${\mathrm{n}}_{\mathrm{core}}=1.8$, the ${\mathrm{胃}}_{\mathrm{i}}$is:

$$\begin{gathered} {\mathrm{蝉颈苍胃}}_{\mathrm{i}}=\frac{1.4}{1.8} \\ {\mathrm{蝉颈苍胃}}_{\mathrm{i}}=0.778 \\ {\mathrm{胃}}_{\mathrm{i}}=51.08掳 \end{gathered}$$

The entire reflection in an optical fibre, the minimum angle ${\mathrm{胃}}_{\mathrm{i}}$is ${\mathrm{胃}}_{\mathrm{i}}鈮�51.06掳$