ρ πε πε

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

R ds z

d y x

z Q y x

V S

 s

 



 



1 2 0

2 2

0 4

1 )

( 4

) , ,

( 

 

2 0

2 2

2 2

2

2 



 



 



 



 z

V y

V x

V V

0 ) , 0 ,

( x z  V

0 as

4 0 , 

 R

R V Q







 R

V 0 , as

) , , ( )

, , (

), , , ( )

, , (

z y x V z

y x V

z y x V z

y x V









 

 



 







 R

R z Q

y x

V 1 1

) 4 , , (

 0

2 / 1 2 2

2 2

/ 1 2 2

2 ( ) ] , [ ( ) ]

[ x y d z R x y d z

R          

y < 0



2 2 2 2 2

2 2

2

sin sin 1

sin 1 1





 



 

 

 

 











 

 

 











 



 V

R V R

R R V R V R

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

Q

2 2 0

2

1 4 ( 2 d )

Q

y 

a F  

2 1 0

2

2 4 ( 2 d )

Q

x 

a F  

) 2 2

] ( ) 2 ( )

2 [(

4 0 1 2 2 2 3 / 2 1 2

2

3 d d

d d

Q

y

x a

a

F 

 



3 2

1 F F

F

F   



D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

r dr r

dr r E

V r l

r r l

r r

0 0

0

2 ln 1

2 0

0 





 







  

i l

i  at d

  



r r r

r r

V r l i

i l

l

M ln

ln 2 ln 2

2 0

0 0

0

0 









  



 

OP OM OM

OP PM

M

P i i





 d

a a

d r

r i i





 d

d i a

 2



 OMP i OPM

d V a

d

V l a l ln

, 2

2 0 ln 1 0

2 





  



) / ln(

0 2

1 V d a

C V  l  

 



d D a

d D

d i

 2









) 4 2 (

1 2 2

a D

D

d   



] 1 )

2 / ( )

2 /

ln[( 2

0



 

a D

a D



) 2 / ( cosh 1

0

a

 D

 

x x

x 2 1 ] cosh 1

ln[    

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

r V M l ln r i

2  0

 

d a r

r i





r

r i

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

P(x,y)

1 2 0

2 ln r V p l r



 



(constant)

1

2 k

r r 



k y

b x

y b

x r

r 







 

 2 2

2 2

1 2

) (

) (

2 2

2 2

2 2

1 ) 2

1

( 1 



 





 

 

 

 b

k y k

k b x k

k b a k

1 2

2 



 b

k c k

1 1

2 2



 



2 2

2 a b

c  



1 for

,

1 for

  



  k  k

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

D

2 1 2

1

2 c a

b  



2 2 2

2

2 c a

b  



D c

c  

 1 2

) 2 (

1 2

2 2

1 2

1 D a a

c  D  



) 2 (

1 2

1 2

2 2

2 D a a

c  D  



D c

c  

 2 1

) 2 (

1 2 2

1 2

2

1 a a D

c  D  



) 2 (

1 2 2

1 2

2

2 a a D

c  D  



D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

4 0 1

0

 



 



 





i i

M r

Q r

V Q

  Q i   Q ?

Q Q r

r i i





 d

 a

d Q Q i   a

 d

d i a

 2



d Q Q a

Q    i 



d a a

d r

r i i







D. K. Cheng, Field and Wave Electromagnetics, 2nd ed., Addison-Wesley, 1989.

) 0 , ( 0

0 at c

Q 



x = 0 x = 0

) 0 , ( 0

0 at c

Q 

 )

0 , ( 1

1 at c

Q 

  Q 1 at (  c 1 , 0 ) )

0 , ( 2

2 at c

Q 

  Q 2 at (  c 2 , 0 )

 

 

 



 

 







  



2 

2 0

0 1 1



  Q

Q Q

k

k c

a

 2

  a

V Q

0 0 0  4 

 



 



 

 







 2 

2 0

0 4 1 1



 

 a V

C Q