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.
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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 80/λ5 |
33/29 |
| (*= λ70 /λ5) |
| 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 |
|
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