BG18

BG18

Longpass filters provide cut-on wavelengths in the ultra-violet (UV), visible, or near-infrared (NIR) spectra. The color glass substrates feature high spectral transmittance within their wavelength ranges. .

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Spectral values guaranteed
τi (350nm) ≥0.3
τi (405nm) ≥0.65
τi (514nm) ≥0.88
τi (633nm) ≤0.25
τi (694nm) ≤0.03
τi (1060nm) ≤0.0005
Download Data sheet
Glass type
 Article L
 W
 T
 Weight

Only values between 1 and 30 with one decimal place are allowed.

SCHOTT
BG18 - BG18
Thickness
1.0
Reflection factor
0.9150
λ [nm]
200 < 10⁻³
210 < 10⁻³
220 < 10⁻³
230 < 10⁻³
240 < 10⁻³
250 < 10⁻³
260 < 10⁻³
270 < 10⁻³
280 < 10⁻³
290 < 10⁻³
300 < 10⁻³
310 < 10⁻³
320 0.033
330 0.156
340 0.305
350 0.416
360 0.497
370 0.552
380 0.603
390 0.643
400 0.682
410 0.719
420 0.751
430 0.780
440 0.806
450 0.830
460 0.853
470 0.872
480 0.885
490 0.899
λ [nm]
500 0.911
510 0.916
520 0.915
530 0.908
540 0.892
550 0.863
560 0.819
570 0.761
580 0.686
590 0.600
600 0.506
610 0.411
620 0.322
630 0.242
640 0.175
650 0.122
660 0.082
670 0.053
680 0.033
690 0.020
700 0.012
710 0.007
720 0.004
730 0.002
740 0.001
750 < 10⁻³
760 < 10⁻³
770 < 10⁻³
780 < 10⁻³
790 < 10⁻³
λ [nm]
800 < 10⁻³
810 < 10⁻³
820 < 10⁻³
830 < 10⁻³
840 < 10⁻³
850 < 10⁻³
860 < 10⁻³
870 < 10⁻³
880 < 10⁻³
890 < 10⁻³
900 < 10⁻³
910 < 10⁻³
920 < 10⁻³
930 < 10⁻³
940 < 10⁻³
950 < 10⁻³
960 < 10⁻³
970 < 10⁻³
980 < 10⁻³
990 < 10⁻³
1,000 < 10⁻³
1,010 < 10⁻³
1,020 < 10⁻³
1,030 < 10⁻³
1,040 < 10⁻³
1,050 < 10⁻³
1,060 < 10⁻³
1,070 < 10⁻³
1,080 < 10⁻³
1,090 < 10⁻³
λ [nm]
1,100 < 10⁻³
1,110 < 10⁻³
1,120 < 10⁻³
1,130 < 10⁻³
1,140 0.001
1,150 0.001
1,160 0.002
1,170 0.002
1,180 0.002
1,190 0.003
1,200 0.003
1,250 0.007
1,300 0.018
1,350 0.033
1,400 0.060
1,450 0.096
1,500 0.150
1,550 0.214
1,600 0.280
1,650 0.359
1,700 0.436
1,750 0.502
1,800 0.560
1,850 0.619
1,900 0.660
1,950 0.707
2,000 0.743
2,050 0.763
2,100 0.781
2,150 0.789
λ [nm]
2,200 0.777
2,250 0.769
2,300 0.770
2,350 0.785
2,400 0.790
2,450 0.786
2,500 0.760
2,550 0.726
2,600 0.680
2,650 0.648
2,700 0.596
2,750 0.426
2,800 0.070
2,850 0.011
2,900 0.004
2,950 0.002
3,000 0.001
3,050 0.001
3,100 < 10⁻³
3,150 < 10⁻³
3,200 < 10⁻³
3,250 < 10⁻³
3,300 < 10⁻³
3,350 < 10⁻³
3,400 < 10⁻³
3,450 < 10⁻³
3,500 < 10⁻³
3,550 < 10⁻³
3,600 < 10⁻³
3,650 < 10⁻³
λ [nm]
3,700 0.001
3,750 0.001
3,800 0.001
3,850 0.001
3,900 < 10⁻³
3,950 < 10⁻³
4,000 < 10⁻³
4,050 < 10⁻³
4,100 < 10⁻³
4,150 < 10⁻³
4,200 < 10⁻³
4,250 < 10⁻³
4,300 < 10⁻³
4,350 < 10⁻³
4,400 < 10⁻³
4,450 < 10⁻³
4,500 < 10⁻³
4,550 < 10⁻³
4,600 < 10⁻³
4,650 < 10⁻³
4,700 < 10⁻³
4,750 < 10⁻³
4,800 < 10⁻³
4,850 < 10⁻³
4,900 < 10⁻³
4,950 < 10⁻³
5,000 < 10⁻³
5,050 < 10⁻³
5,100 < 10⁻³
5,150 < 10⁻³
Reflection factor
Pd 0.915
Reference thickness
d [mm] 1
Spectral values guaranteed
τi (350nm) ≥0.3
τi (405nm) ≥0.65
τi (514nm) ≥0.88
τi (633nm) ≤0.25
τi (694nm) ≤0.03
τi (1060nm) ≤0.0005
Refractive Indices n
nF (486.1 nm) = 1.539
nh (404.7 nm) = 1.546
ng (435.8 nm) = 1.543
ns (852.1 nm) = 1.528
ne (546.1 nm) = 1.536
nd (587.6 nm) = 1.534

Colorimetric evaluation

Illuminant A(Planck T = 2347K)
d [mm] 1 2 3
x 0.361 0.309 0.275
y 0.441 0.459 0.472
Y 61 46 37
λd [nm] 502 501 501
Pe 0.20 0.31 0.39
Illuminant Planck T = 3200 K
d [mm] 1 2 3
x 0.340 0.292 0.260
y 0.426 0.441 0.451
Y 62 48 38
λd [nm] 500 500 500
Pe 0.20 0.32 0.39
Illuminant D65 (TC = 6504 K)
d [mm] 1 2 3
x 0.255 0.225 0.206
y 0.335 0.340 0.346
Y 68 54 45
λd [nm] 493 493 493
Pe 0.21 0.31 0.38
Density
p [g/cm3] 2.6751
Bubble content
Bubble class 2
Transformation temperature
Tg [°C] 457
Temperature coefficient
Tk [nm/°C]
Chemical Resistance
FR class 0
SR class 2.0
AR class 2.0
Thermal expansion
α-30°C/+70°C [10-6/K] 7.44
α20°C/300°C [10-6/K] 8.88
α20°C/200°C [10-6/K]
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