, . (. 8.2). , , ( ).
.8.2 |
, - , , , . , . , , , , .
( ), , L 2, . , j = 0 A 0, , .
j. OC 0 (. 8.5, C j C- j). , j, , , C j ( ), , , C j , OC 0, .
FD, . , FD C j . , FE ED. , FD, , ED , l/2 (. 8.2). - , l/2 . C j , (. ): (z = 2 k), C j , z - (z = 2 k+ 1), C j - . , FE, , ED l/2 .. . ED, j, ED = sin j.
sin j = (2k + 1)l / 2, (8.5)
|
|
sin j = 2 k l /2,(8.6)
k = 1,2,3.. - . k, , . + - (8.5) (8.6) , +j -j L 2: C j C -j, C 0. j = 0 , C 0 .
(8.5)
..
. 8.3 |
. 8.6 sin j. (j = 0) , , . . . 8.3 (8.5) (8.6) , . . l . ( ). ; , . ( j = arcsin l/2), . , . , l .
, .
, , . . , , , , , . 1 - 300 1/ ( ) 1200 1/ ( ).
. 8.4. |
, N a b (.8.4). a + b = d . . , , j . , N ( N ).
|
|
, , (. 8.5) .
. 8.5
. a sin j = k l (8.8).
sin j = l /a, 2l /a,... . 8.5. , , , , . . , , , , , : , .. , . , , , . . 8.5 d a.
. . , (, C E, B F), ED C j. . ED = k l , ED = d sinj,
d sinj = k l, k = 0,1,2..., 8.7)
, C j . :
A max = N A j, (8.8)
A j - , j;
J max = N 2 A j2 = N 2 J j.(8.9)
(8.9) . k .
(8.9)
. (8.10)
C 0, , .. , C 0, +. . 8.5 .
, , . . , 1/23 .
N , N 2 , . , ( 1/ N), ( ). , , .
( ). . , , , ½sinj½ £ 1 (j = p / 2 - ), (8.7)
. (8.11)
, k - .
l. , (k = 0), , . , , .. ( ) . , , , .
|
|
.
. - , .. . , ( 8.9), D - , 1 (. 8.6),
. (8.12)
, (8.7): d cosj d j = k d l,
. (8.13)
. 8.6 |
d k, . (cos j 1)
D = k / d. (8.14)
(.. ) , D, .
, , (. 8.7, a, ) ,
a
.8.7
80% (. 8.7,, ), (l1 l2 ) . , 80% (. 8.7,, ). , .
. R , Dl ( l), () :
R = l / Dl. (8.15)
,
R = kN, (8.16)
N - ; k - .
N.
. 8.8, : 1 - , 2 - - , 3 - ( ) 4; 5 - 6.
. 8.8 . 8.9
, , , . .
. 8.9 , , - , .