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E-mail: grom@newmail.ru The influence of the turbulent pulsations of active medium on the characteristics of the beam wavefront in an unstable confocal optical resonator has been studied. It was shown that, the growth in turbulence may cause significant beam quality degradation.

CO2- , , . . , , u( x, y, z ) exp ( j (t - kz ) ) , u( x, y , z ) :
2u 2u u + 2 - 2 jk =0 2 x y z

(1)

u( x, y, z ) P ( v x , v y )

u ( x, y ) =

P( v x , v y ) exp ( - j 2 v x x - j 2 v y y ) dv x dv

y

(2)

P ( v x , v y ) , , : P( vx , v y ) =

u( x, y ) exp ( ( j 2 v x x + j 2 v y y ) ) dxdy

(3)

, 0 1, P ( v x , v y ) = P0 ( v x , v y ) exp j L ( v x 2 + v y 2 ) , : 1

(

)

L - , P0 ( v x , v y ) , P1 ( v x , v y ) , , 0 1. , [1]. :

=

1 + ( I + I
+

0

-

)

I sat

(4)

, CO2 - : I sat = 1 / 2 , 0 = 0.01 -1 , = 10.6 . , [1]. . , :
2 n ( q) = 0.033 Cn ( q 2 + q0 2 -11 6

)

e

q2 qm2

,

(1)

n ( q ) - , qm , q0 - . , [2]. ( q ) n ( q ) : ( q) = 2 k 2 h n ( q) . . 2 k -1 ( q) , k = , N . n ( q ) .

. : L = 4 ; M = 2.5 ; N eq = 1.5 ;

= 5.33 , Rback = 13.33 ; : a1 = 5.3 , a2 = 9.2 . : 0.46 . : - 512x512, Cn 2 = 1 в 10-10..1 в 10-9 -2/3, - 16, L0 = 9.2 , l0 = 3 . : R
front

, Cn 2 = 1 в 10-10 -2/3 . 80% : 4.4 . Cn 2 = 1 в 10-10 -2/3 6.8 Cn 2 = 1 в 10-9 -2/3, (4.7 ). Cn 2 1 в 10-9 -2/3 "" . : L = 4 ; M = 2.5 ; N eq = 100 ; : R front = 5.33 , Rback = 13.33 ; : a1 = 75.2 , a2 = 188 . : 0.056 . : - 512x512, - 16, Cn 2 = 1 в 10-11..1 в 10-10 -2/3, L0 = 56 , l0 = 3 . Cn 2 = 1 в 10-11 -2/3 (1.97 ), Cn 2 = 1 в 10-10 -2/3 14 , .. .
. ,

. , , .
1. A.E. Siegman, E.A. Sziklas "Mode calculations in unstable resonators with flowing saturable gain. 2: Fast Fourier transform method", Appl. Opt., Vol. 14, p. 1874, 1975 2. J.M. Martin, S.M. Flatte "Intensity images and statistics from numerical simulation of wave propagation in 3-D random media", Appl. Opt, Vol. 27, pp. 21112126, 1988.