% <PLAINTEXT>
% $BNL;RJ*M}3X(B : $B1i=,LdBj(B Q2-1 $B2rEz(B
% $B:n(B  $B@.(B  $B<T(B : h9410159 $BJ?Ln(B $B4n1Q(B
% $B=$(B  $B@5(B  $B<T(B : g140826  $B?eLn(B $BMNJe(B
% $B:n@.G/7nF|(B : 95/12/25
% $B=$@5G/7nF|(B : 01/12/25
% $BEE;R%a!<%k(B : h9410159@edu.cc.uec.ac.jp
% $B=$@5<TEE;R%a!<%k(B : g140826@mail.ecc.u-tokyo.ac.jp
%
% \mondai{$B:n@.<T(B}{$B:n@.G/7nF|(B}{$BEE;R%a!<%k(B}{$BLdBjHV9f(B}{$BLdBjJ8(B}{$B2rEz(B}
%
% $BNL;RNO3X(B $B1i=,LdBj$H2rEz(B

% Q2-1 $BLdBj(B

\mondai
{h9410159 $BJ?Ln(B $B4n1Q(B}
{95/12/25}
{h9410159@edu.cc.uec.ac.jp}
{2-1}
{
 $B?^(B1($B652J=q(Bp.21$B;2>H(B)$B$N$h$&$K!"I}(B $a$ $B$N(B1$B8D$N%9%j%C%H$K!"GH?t(B $ k = 2\pi /
\lambda $ $B$NJ?LLGH$,?/F~$7$?!#$3$l$r(B $L$ $B$@$1N%$l$?%9%/%j!<%s>e$G(B $x$ $B$@$1N%(B
$B$l$?E@$G$N?6I}(B $f(x)$ $B$O(B
\begin{equation}
 f(x) = C \int_{0}^{a} e^{ikyx/L} dy \label{eq:2-1-1}
\end{equation}
$B$H6a;wE*$K=q$1$k$3$H$r<($;(B($C$ $B$ODj?t(B)$B!#$^$?!"$3$N(B $f(x)$ $B$H6/EY(B $ I(x) = |
F(x)|^2 $ $B$r5a$a$h!#$?$@$7(B $ L \gg x $ $B$H$9$k!#(B
}
{
 $B%9%/%j!<%s$NCf?4$+$i(B $x$ $BN%$l$?0LCV$O!"%9%j%C%H$+$i(B $ \sin{\theta} \sim
\tan{\theta} = x/L $ $B$@$179$$$?J}8~$G$"$k!#(B
$B$^$?!"%9%j%C%H$N2<C<(B ($y = 0$) $B$NE@$NGH$H!"2<C<$+$i(B $y$ $BN%$l(B
$B$?E@$NGH$G$O!"%9%/%j!<%s>e$NE@(B $x$ $B$^$G$NF;$N$j$N:9(B $ \Delta \ell $  $B$,(B

\begin{equation}
 \Delta \ell = y \sin{\theta} = \frac{yx}{L} ,
\end{equation}
$B$G$"$k!#$h$C$F!"$3$N#2$D$NGH$N0LAj$N$:$l(B $\Delta \varphi $ $B$O(B

\begin{equation}
 \Delta \varphi = \frac{\Delta \ell}{\lambda} \times 2\pi = \frac{kxy}{L} ,
\end{equation}
$B$7$?$,$C$F!"E@(B $y$ $B$r=PH/$7$?GH$N7A$O!"?6I}$r(B $C$ $B$H$9$k$H(B

\begin{equation}
 C e^{i \Delta \varphi} = C e^{ikyx/L} , \label{eq:2-1-4}
\end{equation}
$B$HI=$5$l$k!#%9%/%j!<%s>e$NE@(B $x$ $B$G4QB,$5$l$kGH$O!"(B$y = 0$
$B$+$i(B $y = a$ $B$^$G$NGH$N=E$M9g$o$;$G$"$k$+$i!"(B$ f(x) $ $B$O(B (\ref{eq:2-1-4})
$B<0$rMQ$$$F(B

\begin{equation}
 f(x) = C \int_{0}^{a} e^{ikyx/L} dy ,
\label{eq:2-1-5}
\end{equation}
$B$HI=$5$l$k!#<0(B(\ref{eq:2-1-5})$B$r7W;;$9$k$H(B

\begin{equation}
 f(x) = C \frac{L}{ikx} \left[ e^{ikyx/L}
\right]_{y=0}^{y=a} = \frac{CL}{ikx}
\left(e^{ikax/L} - 1 \right) ,
\end{equation}
$B$h$C$F6/EY(B $ I(x) $ $B$O(B

\begin{equation}
 I(x) = | f(x) |^2 = \frac{|C|^2 L^2}{k^2 x^2} \left|
e^{ikax/L} - 1 \right|^2 = \frac{4|C|^2 L^2}{k^2
x^2} \sin^{2}{\frac{kax}{2L}} ,
\end{equation}
$B$rF@$k!#(B }
% Q2-1 $B=*(B



