N-BALF4 - Schott 2000

Diagram n (λ)

n calculation

Diagram τ (λ)

τ calculation

Analogue search

Main parameters
n_d = 1.579559 n_e = 1.582121	V_d = 53.86 V_e = 53.58	n_F - n_C = 0.010759 n_F' - n_C' = 0.010863	Coloring: 0.37 - 0.33 mkm.

Type: Sellmeier
Spectral range: 0.3650146 - 2.3254 mkm.
C1 = 1.31004128 C2 = 0.142038259 C3 = 0.964929351 C4 = 0.0079659645 C5 = 0.0330672072 C6 = 109.19732

Refraction index
n _2.3254	1.550681
n _1.9701	1.555774
n _1.5296	1.561237
n _1.06	1.567070
n _t	1.567755
n _s	1.570646
n _r	1.574474
n _C	1.576311
n _C'	1.576826
n _0.6328	1.577308
n _D	1.579463
n _d	1.579559
n _e	1.582121
n _F	1.587070
n _F'	1.587690
n _g	1.593009
n _h	1.597986
n _i	1.606578
n _0.3341	-----
n _0.3126	-----
n _0.2967	-----
n _0.2804	-----
n _0.2483	-----

Relative partial dispertion
P_C,t	0.7952
P_C,A'	0.3412
P_d,C	0.3018
P_e,C	0.5400
P_g,d	1.2501
P_g,F	0.5519
P_h,g	0.4625
P_i,g	1.2611
P_C',t	0.8431
P_e,C'	0.4921
P_F',e	0.5175
P_i,F'	1.7555

transmittance: 10 mm
τ_2.5	0.8
τ_2.3254	0.89
τ_1.9701	0.967
τ_1.5296	0.994
τ_1.06	0.997
τ_0.7	0.999
τ_0.66	0.998
τ_0.62	0.998
τ_0.58	0.998
τ_0.54607	0.998
τ_0.5	0.997
τ_0.46	0.994
τ_0.4358	0.993
τ_0.42	0.992
τ_0.4047	0.988
τ_0.4	0.985
τ_0.39	0.976
τ_0.38	0.959
τ_0.37	0.92
τ_0.365	0.89
τ_0.35	0.68

transmittance: 25 mm
τ_2.5	0.58
τ_2.3254	0.74
τ_1.9701	0.92
τ_1.5296	0.984
τ_1.06	0.993
τ_0.7	0.997
τ_0.66	0.995
τ_0.62	0.995
τ_0.58	0.996
τ_0.54607	0.995
τ_0.5	0.993
τ_0.46	0.986
τ_0.4358	0.983
τ_0.42	0.981
τ_0.4047	0.97
τ_0.4	0.964
τ_0.39	0.94
τ_0.38	0.9
τ_0.37	0.82
τ_0.365	0.75
τ_0.35	0.38

Density: 3.11 g/cm³
Poisson coef.: 0.245
Young module: 770 Pa*10⁸
Knoop hardness: 540
Optical stress coef.: 3.01 1/Pa*10¹²
Abrasion: 2

Climatic resistance: 1
Staining: 0
Resistance to acids: 1
Resistance to alkalis: 1
Phosphate resistance: 1

Temperature coefficient of linear expansion
Temp. range, C	Value, 1/C*10^-7
-30 ~ 70	65
20 ~ 300	74

Temperature coefs. of n_abs
Temp. range, C	Wave length, mkm.	Value, 1/C*10^-6
-40 ~ -20		2
20 ~ 40		2.9
60 ~ 80		3.4
-40 ~ -20	e	2.7
20 ~ 40	e	3.7
60 ~ 80	e	4.3
-40 ~ -20	g	3.4
20 ~ 40	g	4.6
60 ~ 80	g	5.3

Temperature coefs. of n_rel
Temp. range, C	Wave length, mkm.	Value, 1/C*10^-6
-40 ~ -20		4.1
20 ~ 40		4.2
60 ~ 80		4.4
-40 ~ -20	e	4.9
20 ~ 40	e	5.1
60 ~ 80	e	5.4
-40 ~ -20	g	5.6
20 ~ 40	g	6
60 ~ 80	g	6.4