N-SF8 - Schott 2000

Diagram n (λ)

n calculation

Diagram τ (λ)

τ calculation

Analogue search

Main parameters
n_d = 1.688935 n_e = 1.694133	V_d = 31.30 V_e = 31.06	n_F - n_C = 0.022005 n_F' - n_C' = 0.022346	Coloring: 0.41 - 0.36 mkm.

Type: Sellmeier
Spectral range: 0.3650146 - 2.3254 mkm.
C1 = 1.55075812 C2 = 0.209816918 C3 = 1.46205491 C4 = 0.0114338344 C5 = 0.0582725652 C6 = 133.24165

Refraction index
n _2.3254	1.644475
n _1.9701	1.650602
n _1.5296	1.657533
n _1.06	1.666001
n _t	1.667108
n _s	1.672029
n _r	1.679036
n _C	1.682544
n _C'	1.683543
n _0.6328	1.684482
n _D	1.688744
n _d	1.688935
n _e	1.694133
n _F	1.704549
n _F'	1.705889
n _g	1.717749
n _h	1.729482
n _i	1.751509
n _0.3341	-----
n _0.3126	-----
n _0.2967	-----
n _0.2804	-----
n _0.2483	-----

Relative partial dispertion
P_C,t	0.7014
P_C,A'	0.3146
P_d,C	0.2904
P_e,C	0.5266
P_g,d	1.3093
P_g,F	0.5998
P_h,g	0.5331
P_i,g	1.5341
P_C',t	0.7468
P_e,C'	0.4812
P_F',e	0.5342
P_i,F'	2.0731

transmittance: 10 mm
τ_2.5	0.75
τ_2.3254	0.82
τ_1.9701	0.95
τ_1.5296	0.988
τ_1.06	0.997
τ_0.7	0.995
τ_0.66	0.993
τ_0.62	0.993
τ_0.58	0.994
τ_0.54607	0.993
τ_0.5	0.985
τ_0.46	0.976
τ_0.4358	0.965
τ_0.42	0.95
τ_0.4047	0.92
τ_0.4	0.9
τ_0.39	0.83
τ_0.38	0.67
τ_0.37	0.35

transmittance: 25 mm
τ_2.5	0.48
τ_2.3254	0.6
τ_1.9701	0.87
τ_1.5296	0.97
τ_1.06	0.993
τ_0.7	0.987
τ_0.66	0.983
τ_0.62	0.983
τ_0.58	0.986
τ_0.54607	0.983
τ_0.5	0.963
τ_0.46	0.94
τ_0.4358	0.91
τ_0.42	0.88
τ_0.4047	0.81
τ_0.4	0.77
τ_0.39	0.63
τ_0.38	0.37
τ_0.37	0.07

Density: 2.9 g/cm³
Poisson coef.: 0.245
Young module: 880 Pa*10⁸
Knoop hardness: 600
Optical stress coef.: 2.95 1/Pa*10¹²
Abrasion: 4

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	86
20 ~ 300	99

Temperature coefs. of n_abs
Temp. range, C	Wave length, mkm.	Value, 1/C*10^-6
-40 ~ -20		-1.3
20 ~ 40		-0.5
60 ~ 80		-0.1
-40 ~ -20	e	0.1
20 ~ 40	e	1.2
60 ~ 80	e	1.7
-40 ~ -20	g	1.8
20 ~ 40	g	3.3
60 ~ 80	g	4.1

Temperature coefs. of n_rel
Temp. range, C	Wave length, mkm.	Value, 1/C*10^-6
-40 ~ -20		1
20 ~ 40		0.9
60 ~ 80		1
-40 ~ -20	e	2.4
20 ~ 40	e	2.6
60 ~ 80	e	2.9
-40 ~ -20	g	4.2
20 ~ 40	g	4.8
60 ~ 80	g	5.3