BK12 - GOST Rus

Diagram n (λ)

n calculation

Analogue search

Main parameters
n_d = 1.560681 n_e = 1.562972	V_d = 58.34 V_e = 58.07	n_F - n_C = 0.009609 n_F' - n_C' = 0.009693

Type: Resnik
Spectral range: 0.36501 - 2.6 mkm.
C1 = 0.028 C2 = 1.55845 C3 = 0.0177159 C4 = -0.00967665 C5 = -0.00116017 C6 = -0.000380448 C7 = 0.00013508 C8 = 0 C9 = 0 C10 = 0 C11 = 0

Refraction index
n _2.3254	1.533742
n _1.9701	1.538646
n _1.5296	1.543864
n _1.06	1.549334
n _t	1.549968
n _s	1.552623
n _r	1.556103
n _C	1.557762
n _C'	1.558226
n _0.6328	1.558660
n _D	1.560595
n _d	1.560681
n _e	1.562972
n _F	1.567371
n _F'	1.567920
n _g	1.572609
n _h	1.576968
n _i	1.584435
n _0.3341	-----
n _0.3126	-----
n _0.2967	-----
n _0.2804	-----
n _0.2483	-----

Relative partial dispertion
P_C,t	0.8110
P_C,A'	0.3457
P_d,C	0.3037
P_e,C	0.5421
P_g,d	1.2413
P_g,F	0.5450
P_h,g	0.4535
P_i,g	1.2306
P_C',t	0.8593
P_e,C'	0.4938
P_F',e	0.5148
P_i,F'	1.7186

Density: 3.02 g/cm³
Poisson coef.: 0.243
Young module: 759 Pa*10⁸
Optical stress coef.: 2.55 1/Pa*10¹²
Abrasion: 0.9

Climatic resistance: А
Resistance to acids: II

Temperature coefficient of linear expansion
Temp. range, C	Value, 1/C*10^-7
-60 ~ 20	71
0 ~ 30	73
20 ~ 120	77
20 ~ 300	84