Optical constants

Refractive index of Kapton

Sahin et al. 2019: n,k 160–3000 µm

Data
tabulated nk
Range
160–3000 µm
Points
285
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 160–3000 µm
Refractive index n
1.84896
Extinction coefficient k
0.00888578
Permittivity ε1
3.41858
Permittivity ε2
0.0328589
Absorption coefficient α
1.61128 cm⁻¹
Penetration depth δ = λ/(2πk)
1.24125e+07 nm
Abbe number Vd
—
Chromatic dispersion dn/dλ
3.40000e-05 µm⁻¹
Group index ng
1.8254
Group velocity dispersion
— fs²/mm
Dispersion parameter D
— ps/(nm·km)
Photon energy
0.00178909 eV

ε = (n + ik)², α = 4πk/λ, ng = n − λ dn/dλ, GVD = λ³/(2πc²) d²n/dλ², D = −(λ/c) d²n/dλ². Group-velocity dispersion is given for formula data only.

Use it in Lightsmith

Load this data in Python, simulate in one more line

pip install lightsmith
import lightsmith as ls

# Kapton: Sahin et al. 2019: n,k 160–3000 µm
kapton = ls.fetch_refractiveindex("other", "Kapton", "Sahin", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(kapton.range_nm)  # (160000, 3e+06) nm
eps = kapton.eps([693000])  # complex permittivity

Downloads the original record once (pinned to the imported snapshot) and caches it.

Lightsmith is open source (MIT): Mie, T-matrix, BEM, DDA, FDTD, RCWA, TMM, mode solvers and inverse design behind one spec, on CPU or GPU. GitHub.

Comments and conditions

125-μm-thick Kapton HN general purpose polyimide film sample provided by DuPont

References

S. Sahin, N. K. Nahar, K. Sertel. Dielectric properties of low-loss polymers for mmW and THz Applications. J. Infrared Millim. Terahertz Waves 40, 557–573 (2019)
  • doi:10.1007/s10762-019-00584-2 Dielectric Properties of Low-Loss Polymers for mmW and THz Applications, Journal of Infrared, Millimeter, and Terahertz Waves (2019)

Cite

Seckin Sahin, Niru K. Nahar and Kubilay Sertel. Dielectric Properties of Low-Loss Polymers for mmW and THz Applications. Journal of Infrared, Millimeter, and Terahertz Waves, 40, 557-573 (2019), doi:10.1007/s10762-019-00584-2; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

285 rows as published
Kapton, Sahin et al. 2019: n,k 160–3000 µm: n and k versus wavelength
λ (µm)nk
160.01.812440.0157111
170.01.817040.0169473
180.01.820880.0177122
190.01.823460.0182363
200.01.826010.0185507
210.01.829210.0187329
220.01.831310.0187527
230.01.832870.0188781
240.01.834170.0187773
250.01.834970.0184909
260.01.835930.0182867
270.01.837720.0179358
280.01.839370.0177255
290.01.83870.0175487
300.01.840620.0172607
310.01.839730.0169805
320.01.841020.0167107
330.01.841530.01642
340.01.842110.0161103
350.01.842740.0158131
360.01.844520.015548
370.01.842770.015283
380.01.843340.0149996
390.01.844430.0147088
400.01.843360.0144179
410.01.845630.0141779
420.01.84610.0139475
430.01.845480.0137172
440.01.843840.0134814
450.01.845890.013236
460.01.846960.0129907
470.01.844870.0127453
480.01.845160.0125097
490.01.847530.0122979
500.01.847980.012086
510.01.847340.0118742
520.01.846830.0116624
530.01.846410.011464
540.01.846540.0112862
550.01.847670.0111085
560.01.84880.0109307
570.01.847580.0107529
580.01.846140.0105751
590.01.845520.010402
600.01.847340.0102427
610.01.849170.0100834
620.01.850080.00992409
630.01.849070.0097648
640.01.848060.0096055
650.01.847160.00944621
660.01.84760.00928692
670.01.848040.00916001
680.01.848480.00904078
690.01.848860.00892155
700.01.84920.00880231
710.01.849530.00868308
720.01.849860.00856385
730.01.849680.00844461
740.01.848890.00832538
750.01.848090.00820614
760.01.84730.00808691
770.01.84650.00798248
780.01.847150.00788225
790.01.847910.00778203
800.01.848660.00768181
810.01.849420.00758158
820.01.850170.00748136
830.01.850220.00738114
840.01.849610.00728092
850.01.849010.00718069
860.01.848410.00708047
870.01.847810.00698025
880.01.84720.00688002
890.01.847740.0067798
900.01.848350.00668301
910.01.848950.00660352
920.01.849550.00652402
930.01.850160.00644453
940.01.850760.00636503
950.01.851230.00628553
960.01.85110.00620604
970.01.850980.00612654
980.01.850860.00604705
990.01.850730.00596755
1000.01.850610.00588805
1010.01.850480.00580856
1020.01.850360.00572906
1030.01.850230.00564957
1040.01.850060.00557007
1050.01.849840.00549058
1060.01.849620.00541108
1070.01.84940.00533158
1080.01.849180.00525209
1090.01.848950.00518847
1100.01.848730.00514027
1110.01.848510.00509206
1120.01.848290.00504386
1130.01.848650.00499566
1140.01.849010.00494746
1150.01.849370.00489926
1160.01.849730.00485106
1170.01.850090.00480285
1180.01.850440.00475465
1190.01.85080.00470645
1200.01.851160.00465825
1210.01.851520.00461005
1220.01.851880.00456184
1230.01.852240.00451364
1240.01.851960.00446544
1250.01.851570.00441724
1260.01.851170.00436904
1270.01.850780.00432083
1280.01.850380.00427263
1290.01.849980.00422443
1300.01.849590.00417623
1310.01.849190.00412803
1320.01.84880.00407983
1330.01.84840.00403162
1340.01.848010.00398342
1350.01.847610.00393522
1360.01.847210.00388702
1370.01.846960.00383882
1380.01.847270.00379061
1390.01.847570.00375205
1400.01.847870.00371818
1410.01.848180.00368432
1420.01.848480.00365046
1430.01.848790.0036166
1440.01.849090.00358274
1450.01.849390.00354888
1460.01.84970.00351502
1470.01.850.00348116
1480.01.850310.0034473
1490.01.850610.00341344
1500.01.850910.00337958
1510.01.851220.00334572
1520.01.851520.00331186
1530.01.851830.003278
1540.01.852060.00324414
1550.01.851950.00321028
1560.01.851850.00317642
1570.01.851740.00314256
1580.01.851630.0031087
1590.01.851530.00307484
1600.01.851420.00304098
1610.01.851310.00300712
1620.01.85120.00297326
1630.01.85110.0029394
1640.01.850990.00290554
1650.01.850880.00287168
1660.01.850780.00283781
1670.01.850670.00280395
1680.01.850560.00277009
1690.01.850460.00273623
1700.01.850350.00270237
1710.01.850240.00266851
1720.01.850140.00263465
1730.01.850030.00260079
1740.01.849920.00256693
1750.01.849820.00253307
1760.01.849740.00249921
1770.01.849750.00246535
1780.01.849770.00243149
1790.01.849780.00239763
1800.01.849790.00236377
1810.01.84980.00232991
1820.01.849810.00229605
1830.01.849820.00226219
1840.01.849830.00222833
1850.01.849840.00219447
1860.01.849860.00216061
1870.01.849870.00212675
1880.01.849880.00209289
1890.01.849890.00207603
1900.01.84990.00206229
1910.01.849910.00204855
1920.01.849920.00203481
1930.01.849930.00202108
1940.01.849940.00200734
1950.01.849960.0019936
1960.01.849970.00197986
1970.01.849980.00196612
1980.01.849990.00195238
1990.01.850.00193864
2000.01.850010.0019249
2010.01.850020.00191116
2020.01.850030.00189742
2030.01.850040.00188368
2040.01.850060.00186994
2050.01.850070.0018562
2060.01.850130.00184246
2070.01.850180.00182872
2080.01.850230.00181498
2090.01.850280.00180124
2100.01.850340.0017875
2110.01.850390.00177376
2120.01.850440.00176003
2130.01.850490.00174629
2140.01.850540.00173255
2150.01.85060.00171881
2160.01.850650.00170507
2170.01.85070.00169133
2180.01.850750.00167759
2190.01.850810.00166385
2200.01.850860.00165011
2210.01.850910.00163637
2220.01.850960.00162263
2230.01.851010.00160889
2240.01.851070.00159515
2250.01.851120.00158141
2260.01.851170.00156767
2270.01.851220.00155393
2280.01.851280.00154019
2290.01.851330.00152645
2300.01.851380.00151271
2310.01.851430.00149898
2320.01.851480.00148524
2330.01.851540.0014715
2340.01.851590.00145776
2350.01.851640.00144402
2360.01.851690.00143028
2370.01.851750.00141654
2380.01.85180.0014028
2390.01.851850.00138906
2400.01.85190.00137532
2410.01.851950.00136158
2420.01.852010.00134784
2430.01.852060.0013341
2440.01.852110.00132036
2450.01.852160.00130662
2460.01.852150.00129288
2470.01.852080.00127914
2480.01.8520.0012654
2490.01.851920.00125167
2500.01.851850.00123793
2510.01.851770.00122419
2520.01.851690.00121045
2530.01.851620.00119671
2540.01.851540.00118297
2550.01.851460.00116923
2560.01.851380.00115549
2570.01.851310.00114175
2580.01.851230.00112801
2590.01.851150.00111427
2600.01.851080.00110053
2610.01.8510.00108679
2620.01.850920.00107305
2630.01.850850.00105931
2640.01.850770.00104557
2650.01.850690.00103183
2660.01.850610.00101809
2670.01.850540.00100435
2680.01.850460.000990615
2690.01.850380.000976876
2700.01.850310.000963136
2710.01.850230.000949397
2720.01.850150.000935657
2730.01.850080.000921918
2740.01.850.000908178
2750.01.849920.000894439
2760.01.849850.000880699
2770.01.849770.00086696
2780.01.849690.00085322
2790.01.849610.000839481
2800.01.849540.000825741
2810.01.849460.000812002
2820.01.849380.000798263
2830.01.849310.000784523
2840.01.849230.000770784
2850.01.849150.000757044
2860.01.849080.000743305
2870.01.8490.000729565
2880.01.848920.000715826
2890.01.848840.000702086
2900.01.848770.000688347
2910.01.848690.000674607
2920.01.848610.000660868
2930.01.848540.000647128
2940.01.848460.000633389
2950.01.848380.000619649
2960.01.848310.00060591
2970.01.848230.00059217
2980.01.848150.000578431
2990.01.848080.000564692
3000.01.8480.000550952

Optical transmission calculator

Free-standing sample in vacuum, normal incidence
Method
Transmittance T
—
Reflectance R
—

Fresnel reflection calculator

Direction
Rp
—
Rs
—
R = (Rp+Rs)/2
—
Phase φp
—
Phase φs
—
Brewster angle θB
—
Critical angle θC
—