SCHOTT N-BK7 Borosilicate Crown Glass

SCHOTT N-BK7 Borosilicate Crown Glass

N-BK7 Data Sheet

Sydor Optics offers Optical Wedges, Optical Filters, and Witness Samples made from the SCHOTT N-BK7 borosilicate crown glass material. If you have questions or need help selecting the ideal material for your application, please contact a Sales Engineer, who will gladly assist you with your needs or discuss additional options that may be available.

Contact a Sales EngineerDownload N-BK7 Data Sheet

N-BK7

nd= 1.51680 νd= 64.17 nF-nC= 0.008054
ne= 1.51872 νe= 63.96 nF’-nC’= 0.008110

Refractive Indices
λ [nm]
n2325.4 2325.4 1.48921
n1970.1 1970.1 1.49495
n1529.6 1529.6 1.50091
n1060.0 1060.0 1.50669
nt 1014.0 1.50731
ns 852.1 1.50980
nr 706.5 1.51289
nC 656.3 1.51432
nC’ 643.8 1.51472
n632.8 632.8 1.51509
nD 589.3 1.51673
nd 587.6 1.51680
ne 546.1 1.51872
nF 486.1 1.52238
nF’ 480.0 1.52283
ng 435.8 1.52668
nh 404.7 1.53024
ni 365.0 1.53627
n334.1 334.1 1.54272
n312.6 312.6 1.54862
n296.7 296.7
n280.4 280.4
n248.3 248.3
Constants of Dispersion Formula
B1 1.03961212
B2 0.231792344
B3 1.01046945
C1 0.00600069867
C2 0.0200179144
C3 103.560653
Constants of Dispersion dn/dT
D0 1.86 . 10-6
D1 1.31 . 10-8
D2 -1.37 . 10-11
E0 4.34 . 10-7
E1 6.27 . 10-10
λTK[μm] 6.27 . 10-10

Internal Transmittance τi
λ [nm] τi(10mm) τi(25mm)
2500 0.665 0.360
2325 0.793 0.560
1970 0.933 0.840
1530 0.992 0.980
1060 0.999 0.997
700 0.998 0.996
660 0.998 0.994
620 0.998 0.994
580 0.998 0.995
546 0.998 0.996
500 0.998 0.994
460 0.997 0.993
436 0.997 0.992
420 0.997 0.993
405 0.997 0.993
400 0.997 0.992
390 0.996 0.989
380 0.993 0.983
370 0.991 0.977
365 0.988 0.971
350 0.967 0.920
334 0.905 0.780
320 0.770 0.520
310 0.574 0.250
300 0.292 0.050
290 0.063
280
270
260
250
Color Code
λ 805 33/29
(*= λ705)
Remarks
step 0.5 available

Relative Partial Dispersion
Ps,t 0.3098
P C,s 0.5612
Pd,C 0.3076
Pe,d 0.2386
Pg,F 0.5349
Pi,h 0.7483
P’ s,t 0.3076
P’ C’,s 0.6062
P’ d,C’ 0.2566
P’ e,d 0.2370
P’ g,F’ 0.4754
P’ i,h 0.7432
Deviation of Relative Partial Dispersions ΔP from the “Normal Line”
ΔP C,t 0.0216
ΔP C,s 0.0087
ΔPF,e -0.0009
ΔPg,F -0.0009
ΔPi,g 0.0035
Other Properties
α-30/+70°C [10-6/K] 7.1
α+20/+300°C [10-6/K] 8.3
Tg[°C] 557
T10 13.0[°C] 557
T10 7.6[°C] 719
cp[J/(g·K)] 0.858
λ [W/(m·K)] 1.114
ρ [g/cm3] 2.51
E[103N/mm2] 82
μ 0.206
K[10-6mm2/N] 2.77
HK0.1/20 610
HG 3
CR 1
FR 0
SR 1
AR 2.3
PR 2.3

Temperature Coefficients of Refractive Index
Δnrel/ΔT[10-6/K] Δnabs/ΔT[10-6/K]
[°C] 1060.0 e g 1060.0 e g
-40/ -20 2.4 2.9 3.3 0.3 0.8 1.2
+20/ +40 2.4 3.0 3.5 1.1 1.6 2.1
+60/ +80 2.5 3.1 3.7 1.5 2.1 2.7