2.5.8 Refractive index of optical materials
Spectral lines for refractometry
Refracting optical materials are
specified by their refractive indices for a series of wavelengths. Those listed
below were recommended by the International Commission for Optics in 1962
(Optica Acta, 1963, 10, 217), and are quoted to the nearest 0.1
nm for standard air. The source element and the designating letter used for
some wavelengths (mainly in the visible spectral region) are shown. A number of
other spectral lines at which refractive indices have been frequently quoted is
also given, including some commonly used laser wavelengths.
Gas discharge lamps are available as
sources over a wide range of wavelengths, and in some instances the spectra of
two or three elements may be combined in one lamp. Interference filters give
the most complete suppression of unwanted lines.
|
Source
|
|
Designating letter
|
Source
|
|
Designating letter
|
|
ICO 1962 |
Other commonly used lines |
|
Recommended standard lines |
|
|
|
|
|
|
|
|
Zn |
213.9 |
|
Hg |
365.0 |
|
i |
|
Hg |
237.8 |
|
Hg |
365.5 |
|
|
Hg |
269.9 |
|
H |
434.0 |
|
G´ |
|
Hg |
289.4 |
|
H |
486.1 |
|
F |
|
Hg |
296.7 |
|
Hg |
577.0 |
|
|
Hg |
334.2 |
|
Hg |
579.0 |
 |
|
|
D |
|
C |
|
|
Hg |
366.3 |
|
Na |
589.0 |
|
Hg |
404.7 |
h |
Na |
589.6 |
|
Hg |
435.8 |
g |
H |
656.3 |
|
|
Cd |
467.8 |
|
K |
766.5 |
|
|
Cd |
508.6 |
|
K |
769.9 |
|
|
Hg |
546.1 |
e |
Hg |
1357.0 |
|
|
He |
587.6 |
d |
Hg |
1367.3 |
|
|
Cd |
643.8 |
C′ |
Common laser wavelengths |
|
He |
667.8 |
|
|
He |
706.5 |
r |
|
Rb |
780.0 |
|
Ar |
488.0 |
|
|
Cs |
852.1 |
s |
Ar |
514.5 |
|
|
Cs |
894.4 |
|
He–Ne |
543.4 |
|
|
Hg |
1014.0 |
t |
Kr |
568.2 |
|
|
Hg |
1128.7 |
|
He–Ne |
593.9 |
|
|
Hg |
1395.1 |
|
He–Ne |
611.8 |
|
|
Hg |
1529.5 |
|
He–Ne |
632.8 |
|
|
Hg |
1813.1 |
|
Kr |
647.0 |
|
|
Hg |
1970.1 |
|
Ruby |
694.3 |
|
|
He |
2058.1 |
|
|
|
|
|
Hg |
2325.4 |
|
|
|
|
|
Hg |
239.9 |
|
Nd |
1.06 |
|
|
Hg |
275.3 |
|
Nd-YAG |
1.065 |
|
|
Hg |
292.5 |
|
He–Ne |
1.52 |
|
|
Hg |
390.6 |
|
He–Ne |
3.39 |
|
|
Cd |
480.0 |
F´ |
CO2 |
10.6 |
|
|
Rb |
794.7 |
|
|
|
|
|
|
|
|
|
|
|
Refractive indices of optical glasses
Optical glasses are available in a wide
range of refractive indices and dispersions. Data are usually given in the
following way:
| |
Refractive index for the helium d
line (587.6 nm), |
nd |
| |
and for the mercury e line (546.1 nm), |
ne |
| |
Mean dispersion between the
hydrogen F line (486.1 nm) and C line (656.3 nm), |
nF −
nC |
| |
and between
the cadmium F' line (480.0 nm) and C' line (643.8 nm),
|
nF' −
nC' |
| |
Reciprocal dispersive power (or
constringence), |
Vd
= (nd − l)/(nF −
nC) |
| |
and |
Ve
= (ne −
1)/(nF' −
nC') |
Refractive indices are generally quoted
for a number of wavelengths. Partial dispersions, for example
(nd − nC) or
(ne − nd), and relative
partial dispersions, for example (ne −
nd)/(nF −
nC) or (ne −
nd)/(nF' −
nC'), may also be stated.
A six-figure reference number for each
glass is obtained from the first three significant figures of the term
(nd − 1) and the first three significant
figures of Vd. For example, BSC 517642 is a
borosilicate crown glass with nd = 1.51680 and
Vd = 64.17. Glasses with
nd less than 1.6 and Vd greater than 55,
and with nd greater than 1.6 and Vd greater
than 50, are described as crowns and the remainder as flints.
Some data from a selection of optical
glasses manufactured by Pilkington Special Glass Limited are given in the table
for borosilicate crown, hard crown, dense barium crown, zinc crown, borate
flint, light flint, dense flint, low density flint, double extra dense flint,
lanthana crown and lanthana flint glasses. The refractive indices are quoted at
a temperature of 20 °C and at standard atmospheric pressure (101 325
Pa).
Optical glasses
Some data for Pilkington Special Glass Limited optical
glasses
(For compelete range of optical glasses see Pilkington Special
Glass Limited catalogue)
|
Refractive index |
nd |
nF−nC |
Vd |
ne |
nF´−
nC´ |
Ve |
ni |
nh |
ng |
nF´ |
nC |
ns |
nt |
|
|
587.56 |
486.13−
656.28 |
|
546.07 |
479.99−
643.85 |
|
365.02 |
404.66 |
435.84 |
479.99 |
656.28 |
852.11 |
1014.00 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
BSC 517642 |
1.516 80 |
0.008 054 |
64.17 |
1.518 72 |
0.008 110 |
63.96 |
1.536 26 |
1.530 24 |
1.526 68 |
1.522 83 |
1.514 32 |
1.509 82 |
1.507 34 |
|
HC 524592 |
1.524 00 |
0.008 850 |
59.21 |
1.526 11 |
0.008 925 |
58.95 |
1.545 77 |
1.538 96 |
1.534 96 |
1.530 66 |
1.521 30 |
1.516 53 |
1.514 03 |
|
DBC 589613 |
1.589 13 |
0.009 615 |
61.27 |
1.591 42 |
0.009 691 |
61.03 |
1.612 65 |
1.605 32 |
1.601 01 |
1.596 35 |
1.586 19 |
1.580 91 |
1.587 07 |
|
DBC 620603 |
1.620 41 |
0.010 284 |
60.33 |
1.622 86 |
0.010 368 |
60.08 |
1.645 60 |
1.637 74 |
1.633 13 |
1.628 14 |
1.617 27 |
1.611 70 |
1.608 76 |
|
ZC 508612 |
1.508 47 |
0.008 310 |
61.19 |
1.510 45 |
0.008 380 |
60.92 |
1.528 68 |
1.522 39 |
1.518 70 |
1.514 71 |
1.505 92 |
1.501 30 |
1.498 77 |
|
LAC 697564 |
1.696 73 |
0.012 349 |
56.42 |
1.699 68 |
0.012 448 |
56.21 |
1.727 09 |
1.717 59 |
1.712 02 |
1.706 03 |
1.692 97 |
1.686 28 |
1.682 71 |
|
Bor F 613443 |
1.613 40 |
0.013 848 |
44.30 |
1.616 09 |
0.013 998 |
44.06 |
1.649 04 |
1.637 44 |
1.630 85 |
1.623 90 |
1.609 24 |
1.601 97 |
1.598 22 |
|
LF 579411 |
1.578 60 |
0.014 070 |
41.12 |
1.581 94 |
0.014 249 |
40.84 |
1.615 95 |
1.603 55 |
1.596 60 |
1.589 34 |
1.574 44 |
1.567 49 |
1.564 19 |
|
DF 620364 |
1.620 04 |
0.017 050 |
36.37 |
1.642 08 |
0.017 283 |
36.11 |
1.666 28 |
1.650 64 |
1.642 02 |
1.633 10 |
1.615 03 |
1.606 74 |
1.602 83 |
|
LDF 706303 |
1.705 85 |
0.023 295 |
30.30 |
1.711 35 |
0.023 662 |
30.06 |
1.772 11 |
1.748 83 |
1.736 37 |
1.723 80 |
1.699 09 |
1.687 98 |
1.682 81 |
|
DEDF 755276 |
1.755 20 |
0.027 383 |
27.58 |
1.761 67 |
0.027 829 |
27.37 |
1.833 36 |
1.805 89 |
1.791 21 |
1.776 36 |
1.747 30 |
1.734 57 |
1.728 89 |
|
LAF 744447 |
1.744 00 |
0.016 638 |
44.72 |
1.747 96 |
0.016 828 |
44.45 |
1.786 97 |
1.772 97 |
1.765 01 |
1.756 63 |
1.739 02 |
1.730 47 |
1.726 18 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Optical plastics
Refractive index, n, and
reciprocal dispersive power, V, are given for four commonly used optical
plastics. The data have been gathered from a variety of sources, including the
manufacturer, and are subject to change as more information is generated.
|
Refractive index
Wavelength/nm |
nF
486.1 |
nD
589.3 |
nC
656.3 |
V |
|
|
|
|
|
|
|
Methyl methacrylate (acrylic) |
1.498 |
1.492 |
1.489 |
57.2 |
|
Polystyrene (styrene) |
1.604 |
1.590 |
1.585 |
30.8 |
|
Polycarbonate |
1.598 |
1.584 |
1.578 |
30.1 |
|
Methyl methacrylate styrene copolymer (NAS) |
1.574 |
1.563 |
1.558 |
33.5 |
|
|
|
|
|
|
Refractive indices of optical cements
Refractive index,
nD20, for the wavelength 589.3 nm (mean of sodium
D lines) at a temperature of 20 °C is given for a number of
well-tried polymerized cements (Optica Acta, 1967, 14,
401). With the increasing availability of new resins for optical purposes,
inspection of manufacturer’s data is recommended to determine the most
appropriate cement for a specific application.
|
Cement |
|
Cement |
|
|
|
|
|
|
|
Solid Canada balsam
. . . . . . |
1.54 |
Beetle 8128
. . . . |
1.55 |
|
Soft Canada
balsam . . . . . . |
1.53 |
BS No. 8
. . . . . . |
1.59† |
|
Cellulose caprate
. . . . . . . |
1.47 |
Epikote 817 |
c.1.57† |
|
Cellulose caprate
(plasticized) . . . . |
1.49 |
Crystic 191 LV |
1.56† |
|
H.T . . . . .
. . . . . . |
1.45 |
Loctite 357 (UV curing) |
1.47† |
|
|
|
|
|
Refractive indices of calcite (Iceland
Spar)
(From 200 nm to 706 nm at 18 °C, and from 801 nm to
3324 nm at 20 °C)
|
|
Refractive index |
|
Refractive index |
|
O-ray |
E-ray |
O-ray |
E-ray |
|
|
|
|
|
|
|
|
200 |
1.902 84 |
1.576 49 |
1422 |
1.635 90 |
|
|
303 |
1.719 59 |
1.513 65 |
1497 |
1.634 57 |
1.477 44 |
|
410 |
1.680 14 |
1.496 40 |
1609 |
1.632 61 |
|
|
508 |
1.665 27 |
1.489 56 |
1682 |
1.631 27 |
|
|
643 |
1.655 04 |
1.484 90 |
1749 |
|
1.476 38 |
|
706 |
1.652 07 |
1.483 53 |
1761 |
1.629 74 |
|
|
801 |
1.648 69 |
1.482 16 |
1849 |
1.628 00 |
|
|
905 |
1.645 78 |
1.480 98 |
1909 |
|
1.475 73 |
|
1042 |
1.642 76 |
1.479 85 |
1946 |
1.626 02 |
|
|
1159 |
1.640 51 |
1.479 10 |
2053 |
1.623 72 |
|
|
1229 |
1.639 26 |
1.478 70 |
2100 |
|
1.474 92 |
|
1307 |
1.637 89 |
1.478 31 |
2172 |
1.620 99 |
|
|
1396 |
1.636 37 |
1.477 89 |
3324 |
|
1.473 92 |
|
|
|
|
|
|
|
Refractive indices of crystal quartz at 20
°C
|
|
Refractive index |
|
Refractive index |
|
O-ray |
E-ray |
O-ray |
E-ray |
|
|
|
|
|
|
|
|
185 |
1.675 78 |
1.689 88 |
1541.4 |
1.527 81 |
1.536 30 |
|
198 |
1.650 87 |
1.663 94 |
1681.5 |
1.525 83 |
1.534 22 |
|
231 |
1.613 95 |
1.625 55 |
1761.4 |
1.524 68 |
1.533 01 |
|
340 |
1.567 47 |
1.577 37 |
1945.7 |
1.521 84 |
1.530 04 |
|
394 |
1.558 46 |
1.568 05 |
2053.1 |
1.520 05 |
1.528 23 |
|
434 |
1.553 96 |
1.563 39 |
2300 |
1.515 61 |
|
|
508 |
1.548 22 |
1.557 46 |
2600 |
1.509 86 |
|
|
589.3 |
1.544.24 |
1.553 35 |
3000 |
1.499 53 |
|
|
768 |
1.539 03 |
1.547 94 |
3500 |
1.484 51 |
|
|
832.5 |
1.537 73 |
1.546 61 |
4000 |
1.466 17 |
|
|
991.4 |
1.535 14 |
1.543 92 |
4200 |
1.456 9 |
|
|
1159.2 |
1.532 83 |
1.541 52 |
5000 |
1.417 |
|
|
1307.0 |
1.530 90 |
1.539 51 |
6450 |
1.274 |
|
|
1395.8 |
1.529 77 |
1.538 32 |
7000 |
1.167 |
|
|
1479.2 |
1.528 65 |
1.537 16 |
|
|
|
|
|
|
|
|
|
|
Refractive indices of synthetic materials at 20
°C
| |
Refractive index |
|
|
Synthetic
fused
silica |
Calcium
fluoride |
Lithium
fluoride |
|
|
|
|
|
|
213.86 |
1.534 30 |
1.484 96 |
1.432 29 |
|
237.83 |
1.514 72 |
1.472 15 |
1.422 56 |
|
239.94 |
1.513 36 |
1.471 25 |
1.421 86 |
|
269.89 |
1.498 04 |
1.460 98 |
1.413 93 |
|
275.28 |
1.495 91 |
1.459 54 |
1.412 80 |
|
289.36 |
1.490 99 |
1.456 20 |
1.410 18 |
|
292.54 |
1.489 99 |
1.455 52 |
1.409 65 |
|
296.73 |
1.488 73 |
1.454 67 |
1.408 97 |
|
334.15 |
1.479 77 |
1.448 52 |
1.404 10 |
|
366.33 |
1.474 35 |
1.444 79 |
1.401 11 |
|
404.66 |
1.469 62 |
1.441 52 |
1.398 47 |
|
435.84 |
1.466 69 |
1.439 50 |
1.396 83 |
|
467.82 |
1.464 29 |
1.437 85 |
1.395 47 |
|
479.99 |
1.463 50 |
1.437 31 |
1.395 02 |
|
486.13 |
1.463 12 |
1.437 05 |
1.394 80 |
|
508.58 |
1.461 86 |
1.436 18 |
1.394 08 |
|
546.07 |
1.460 08 |
1.434 97 |
1.393 05 |
|
587.56 |
1.458 46 |
1.433 89 |
1.392 11 |
|
632.80 |
1.457 02 |
|
1.391 26 |
|
643.85 |
1.456 70 |
1.432 72 |
1.391 07 |
|
769.90 |
1.453 86 |
1.430 91 |
1.389 35 |
|
780.02 |
1.453 67 |
1.430 79 |
1.389 24 |
|
794.76 |
1.453 41 |
1.430 63 |
1.389 07 |
|
852.11 |
1.452 47 |
1.430 07 |
1.388 49 |
|
894.35 |
1.451 84 |
1.429 71 |
1.388 09 |
|
1014.0 |
1.450 24 |
1.428 84 |
1.387 07 |
|
1060.0 |
1.449 68 |
|
1.386 70 |
|
1128.7 |
1.448 87 |
1.428 15 |
1.386 17 |
|
1395.1 |
1.445 83 |
1.426 80 |
1.384 10 |
|
1529.5 |
1.444 27 |
1.426 17 |
1.383 02 |
|
1813.1 |
1.440 71 |
1.424 83 |
1.380 56 |
|
1970.1 |
1.438 53 |
1.424 06 |
1.379 09 |
|
2058.1 |
1.437 23 |
1.423 61 |
1.378 22 |
|
2325.4 |
1.432 93 |
1.422 16 |
1.375 30 |
|
2800.0 |
|
1.419 23 |
1.369 37 |
|
3400.0 |
|
1.414 87 |
1.360 32 |
|
4000.0 |
|
1.409 63 |
1.349 37 |
|
4600.0 |
|
1.403 57 |
1.336 40 |
|
5000.0 |
|
1.399 08 |
1.326 56 |
|
5600.0 |
|
|
1.309 88 |
|
5893.2 |
|
1.387 12 |
|
|
6000.0 |
|
|
1.297 40 |
|
7071.8 |
|
1.368 05 |
|
|
8250.0 |
|
1.344 40 |
|
|
9429.1 |
|
1.316 05 |
|
|
|
|
|
|
Refractive indices and useful transmission
ranges of other optical materials
Values at or near a temperature of 20 °C.
|
Infrared materials |
|
Refractive
index |
|
|
|
|
|
|
|
Arsenic trisulphide
. . . . . |
1.00 |
2.4777 |
0.6 to 13 |
|
|
10.00 |
2.3816 |
|
|
Barium fluoride
. . . . . . |
0.546 |
1.4759 |
0.15 to 12.5 |
|
|
10.346 |
1.3964 |
|
|
Cadmium telluride
. . . . . |
1.00 |
2.838 |
0.9 to ~ 16 |
|
(Irtran 6) |
10.00 |
2.672 |
|
|
Caesium bromide
. . . . . |
1.0 |
1.6779 |
0.22 to 55 |
|
|
39.0 |
1.5624 |
|
|
Caesium iodide
. . . . . |
1.00 |
1.7572 |
0.25 to 55 |
|
|
50.0 |
1.6366 |
|
|
Diamond
. . . . . . . |
0.546 |
2.4235 |
~ 0.25 to > 80 |
|
Gallium arsenide
. . . . . |
10.0 |
3.135 |
1 to ~ 15 |
|
Germanium
. . . . . . |
10.00 |
4.0032 |
1.8 to 23 |
|
Lead fluoride
. . . . . . |
0.55 |
1.7722 |
0.25 to ~ 16 |
|
|
10.00 |
1.6367 |
|
|
Magnesium oxide
. . . . |
1.00 |
1.7227 |
0.3 to 7 |
|
(Irtran 5) |
8.00 |
1.4824 |
|
|
Potassium bromide
. . . |
0.546 |
1.5639 |
0.23 to 25 |
|
|
21.18 |
1.4866 |
|
|
Potassium chloride
. . . |
0.546 |
1.4932 |
0.21 to 20 |
|
|
20.4 |
1.389 |
|
|
Potassium iodide
. . . |
0.546 |
1.6731 |
~ 0.25 to ~ 45 |
|
|
20 |
1.5964 |
|
|
Silicon
. . . . . . . |
10.00 |
3.4170 |
1.2 to 10 |
|
Silver chloride
. . . . |
1.0 |
2.0224 |
0.4 to 30 |
|
|
20.0 |
1.9069 |
|
|
Sodium chloride
. . . |
0.50 |
1.5516 |
0.2 to 20 |
|
|
20.0 |
1.3822 |
|
|
Sodium
fluoride . . . . . . |
0.546 |
1.3264 |
0.15 to 14 |
|
|
10.3 |
1.233 |
|
|
Strontium
titanate . . . . . . |
0.56 |
2.4254 |
0.39 to 6.8 |
|
|
5.00 |
2.1221 |
|
|
Thallium
bromo-iodide . . . . |
0.54 |
2.6806 |
0.6 to 40 |
|
(KRS 5) |
30.0 |
2.2887 |
|
|
Zinc
selenide . . . . . . |
1.00 |
2.485 |
0.45 to ~ 21.5 |
|
(Irtran 4) |
15.00 |
2.370 |
|
|
Zinc
sulphide . . . . . . |
1.00 |
2.2907 |
1.0 to 14.5 |
|
(Irtran 2) |
12.00 |
2.1688 |
|
|
Zinc
sulphide . . . . . . |
0.546
|
2.3884 |
0.37 to 14 |
|
(Cleartran) |
12.00 |
2.1710 |
|
|
|
|
|
|
For some useful data see Chrystran Limited Optical
Crystals Handbook.
| Birefringent
materials |
|
Refractive index |
Transmission
range/μm |
|
O-ray |
E-ray |
|
|
|
|
|
|
|
Ammonium dihydrogen
phosphate . . . . |
0.546 |
1.5266 |
1.4808 |
0.13 to ~ 1.7 |
|
(ADP) |
1.014 |
1.5084 |
1.4690 |
|
|
Potassium dihydrogen phosphate
. . . . |
0.546 |
1.5115 |
1.4698 |
0.25 to ~ 1.7 |
|
(KDP) |
1.014 |
1.4954 |
1.4604 |
|
|
Magnesium
fluoride . . . . . . . . |
0.546 |
1.3786 |
1.3904 |
0.11 to 7.5 |
|
|
1.083 |
1.3731 |
1.3846 |
|
|
Rutile . . . . . . . . . . . . . |
0.546 |
2.652 |
2.958 |
~ 0.43 to 6.2 |
|
(Titanium
dioxide) |
1.014 |
2.484 |
2.747 |
|
|
Sapphire . . . . . . . . . . . . |
0.546 |
1.7708 |
— |
0.15 to 5.5 |
|
(Aluminium oxide) |
1.014 |
1.7555 |
1.7479 |
|
|
|
|
|
|
|
Refractive indices of liquids
Suitable media for refractometry.
Refractive index for the wavelength 589.3
nm (mean of sodium D lines) and temperature of 20 °C or close to 20
°C.
|
Liquid |
Refractive index |
|
|
|
|
Water . . . . . . . . . . . . |
1.333 |
|
Paraldehyde . . . . . . . . . . |
1.405 |
|
Carbon
tetrachloride . . . . . . . |
1.46 |
|
Glycerol . . . . . . . . . . . |
1.47 |
|
Liquid
paraffin . . . . . . . . . . |
1.48 |
|
Toluene . . . . . . . . . . . . |
1.497 |
|
Benzene . . . . . . . . . . . . |
1.501 |
|
Ethyl
salicylate . . . . . . . . . . |
1.523 |
|
Chlorobenzene . . . . . . . . . . |
1.525 |
|
Methyl
salicylate . . . . . . . . . . |
1.538 |
|
Ethyl
cinnamate . . . . . . . . . |
1.559 |
|
Benzyl
benzoate . . . . . . . . . |
1.568 |
|
Aniline . . . . . . . . . . . . |
1.586 |
|
Quinoline . . . . . . . . . . . |
1.627 |
|
α-Monobromonaphthalene . . . . . |
1.660 |
|
Methylene
iodide . . . . . . . . . |
1.737 |
|
Methylene iodide and sulphur
(saturated) |
1.78 |
|
Oil,
paraffin . . . . . . . . . . . |
1.44 |
|
Oil,
olive . . . . . . . . . . . . |
1.46 |
|
Oil,
turpentine . . . . . . . . . . |
1.47 |
|
Oil,
cedar . . . . . . . . . . . |
1.516 |
|
Oil,
cloves . . . . . . . . . . . |
1.532 |
|
Oil,
cinnamon . . . . . . . . . . |
1.601 |
|
|
|
Calibration of liquid refractometers
Liquid of known refractive index,
n, may be used to calibrate critical angle and Vee-block refractometers
throughout the visible spectral region, and over a small range of ambient
temperatures using the temperature coefficient of refractive index,
dn/dt.
|
|
Distilled water |
|
n20 °C |
dn/dt per °C
(20 °C–25
°C) |
|
|
|
|
|
404.66 |
1.342 742 |
− 0.000 101 |
|
435.84 |
1.340 210 |
− 0.000 100 |
|
486.13 |
1.337 123 |
− 0.000 099 |
|
546.07 |
1.334 466 |
− 0.000 098 |
|
587.56 |
1.333 041 |
− 0.000 097 |
|
589.30 |
1.332 988 |
− 0.000 097 |
|
632.80 |
1.331 745 |
− 0.000 096 |
|
656.28 |
1.331 151 |
− 0.000 096 |
|
706.52 |
1.330 020 |
− 0.000 095 |
|
|
|
|
Light transmission, Pilkington Special Glass Limited
optical glass
Internal transmittance, T25, is
defined as the ratio of radiant flux reaching the exit surface of a plane
parallel plate of glass 25 mm thick to the flux which leaves the entry
surface.
|
Glass
type |
BSC
517642 |
HC
524592 |
DBC
589613 |
ZC
508612 |
LAC
697564 |
LF
579411 |
LDF
706303 |
DEDF
755276 |
LAF
744447 |
|
|
Internal transmittance, T25 |
|
|
|
|
|
|
|
|
|
|
|
|
360 |
0.901 |
0.918 |
0.715 |
0.787 |
0.629 |
0.816 |
— |
0.109 |
0.271 |
|
380 |
0.962 |
0.939 |
0.898 |
0.894 |
0.844 |
0.908 |
0.342 |
0.508 |
0.631 |
|
400 |
0.981 |
0.977 |
0.963 |
0.965 |
0.937 |
0.969 |
0.768 |
0.785 |
0.838 |
|
420 |
0.982 |
0.982 |
0.980 |
0.975 |
0.972 |
0.974 |
0.886 |
0.907 |
0.931 |
|
440 |
0.983 |
0.980 |
0.983 |
0.980 |
0.983 |
0.973 |
0.922 |
0.955 |
0.964 |
|
460 |
0.987 |
0.981 |
0.985 |
0.989 |
0.989 |
0.978 |
0.939 |
0.975 |
0.978 |
|
500 |
0.992 |
0.990 |
0.991 |
0.995 |
0.994 |
0.984 |
0.966 |
0.989 |
0.990 |
|
|
|
|
|
|
|
|
|
|
|
In the wavelength range 500 nm to 1000 nm,
T25
 0.970 for the glasses shown in the Table. Data taken from
Pilkington Special Glass Limited catalogue.
References
W. G. Driscoll (ed.) (1978) Handbook of the Optical
Society of America, McGraw-Hill Book Co, Chapter 7.
D. E. Gray (ed.)
(1972) Handbook of the American Institute of Physics, McGraw-Hill Book
Co, Section 6.
E. D. Palik (ed.) (1985) Handbook of Optical Constants of
Solids, Academic Press, London.
E. D. Palik (ed.) (1991) Handbook of
Optical Constants of Solids II, Academic Press, London.
M.Debenham
|
