BK8 - GOST Rus

Diagram n (λ)

n calculation

Analogue search

Main parameters
n_d = 1.546782 n_e = 1.548860	V_d = 62.77 V_e = 62.54	n_F - n_C = 0.008710 n_F' - n_C' = 0.008775

Type: Resnik
Spectral range: 0.36501 - 2.6 mkm.
C1 = 0.028 C2 = 1.54226 C3 = 0.0157448 C4 = -0.0115751 C5 = -0.00113229 C6 = -0.000603698 C7 = 0.000116393 C8 = 0 C9 = 0 C10 = 0 C11 = 0

Refraction index
n _2.3254	1.518351
n _1.9701	1.524172
n _1.5296	1.530175
n _1.06	1.536045
n _t	1.536686
n _s	1.539293
n _r	1.542578
n _C	1.544111
n _C'	1.544538
n _0.6328	1.544936
n _D	1.546704
n _d	1.546782
n _e	1.548860
n _F	1.552822
n _F'	1.553314
n _g	1.557503
n _h	1.561374
n _i	1.567959
n _0.3341	-----
n _0.3126	-----
n _0.2967	-----
n _0.2804	-----
n _0.2483	-----

Relative partial dispertion
P_C,t	0.8524
P_C,A'	0.3547
P_d,C	0.3065
P_e,C	0.5451
P_g,d	1.2308
P_g,F	0.5374
P_h,g	0.4443
P_i,g	1.2003
P_C',t	0.9014
P_e,C'	0.4961
P_F',e	0.5112
P_i,F'	1.6813

Density: 2.85 g/cm³
Poisson coef.: 0.229
Rigidity: 326.5 Pa*10⁸
Young module: 802.6 Pa*10⁸
Optical stress coef.: 2.85 1/Pa*10¹²
Abrasion: 0.8

Climatic resistance: А
Resistance to acids: III

Temperature coefficient of linear expansion
Temp. range, C	Value, 1/C*10^-7
-60 ~ 20	56
0 ~ 30	58
20 ~ 120	62
20 ~ 300	68

Temperature coefs. of n_abs
Temp. range, C	Wave length, mkm.	Value, 1/C*10^-6
-60 ~ 20	F	1.9
-60 ~ 20	e	1.6
-60 ~ 20	D	1.4
-60 ~ 20	C	1.3
20 ~ 120	F	3.5
20 ~ 120	e	3.2
20 ~ 120	D	3
20 ~ 120	C	2.9