Optical constants

Refractive index of S-TIL26 (OHARA)

S-TIL26: n,k 0.35–2.4 µm

Data
formula 2 + tabulated k
Range
0.35–2.4 µm
Temperature
298 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.35–2.4 µm
Refractive index n
1.56732
Extinction coefficient k
9.36134e-09
Permittivity ε1
2.45649
Permittivity ε2
2.93444e-08
Absorption coefficient α
0.00200201 cm⁻¹
Penetration depth δ = λ/(2πk)
9.98996e+09 nm
Abbe number Vd
42.817
Chromatic dispersion dn/dλ
-0.0675447 µm⁻¹
Group index ng
1.60701
Group velocity dispersion
126.9 fs²/mm
Dispersion parameter D
-692.308 ps/(nm·km)
Photon energy
2.11001 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

# S-TIL26 (OHARA): S-TIL26
ohara_s_til26 = ls.fetch_refractiveindex("specs", "OHARA-optical", "S-TIL26", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ohara_s_til26.range_nm)  # (350, 2400) nm
eps = ohara_s_til26.eps([633])  # 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.

Dispersion formula

Sellmeier (C in µm²) (formula 2), λ in µm
n2−1=1.31066488λ2λ2−0.00968897812+0.0941903094λ2λ2−0.0527763106+1.23292644λ2λ2−133.296422

Valid from 0.35 to 2.4 µm.

Coefficients as stored
CiValue
C10.0
C21.31066488
C30.00968897812
C40.0941903094
C50.0527763106
C61.23292644
C7133.296422

Comments and conditions

Recommended - Lightweight

Conditions

temperature
298 K

Properties

thermal dispersion
type: formula A, coefficients: 8.85e-07 1.27e-08 -3.61e-11 5.87e-07 6.12e-10 0.27
nd
1.567322
Vd
42.817076
glass code
567428
density
value: 2570
thermal expansion
value: 7.9e-06, temperature range: 243 343; value: 9e-06, temperature range: 293 573
dPgF
0.0009
resistance
acid: 1.0; climatic: 1.0; phosphate: 1.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 298.0 K): dn/dT = 1.24e-06 K⁻¹ at 633 nm, dn/dT = 5.61e-07 K⁻¹ at 1310 nm, dn/dT = 5.11e-07 K⁻¹ at 1550 nm

References

Cite

OHARA Zemax catalog 2017-11-30 (obtained from http://www.ohara-inc.co.jp); See also OHARA glass data sheets; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

Computed on 423 wavelengths, the same grid as the API and the library
S-TIL26 (OHARA), S-TIL26: n and k versus wavelength
λ (µm)nk
0.351.6085977.406600e-06
0.3516931.6078586.550873e-06
0.3533941.6071315.691007e-06
0.3551031.6064164.826982e-06
0.3568211.6057143.958778e-06
0.3585471.6050223.086375e-06
0.361.6044522.351900e-06
0.3602811.6043432.310692e-06
0.3620241.6036742.055332e-06
0.3637751.6030161.798738e-06
0.3655351.6023681.540902e-06
0.3673031.601731.281819e-06
0.3690791.6011031.021483e-06
0.371.6007838.865600e-07
0.3708641.6004858.433374e-07
0.3726581.5998777.536447e-07
0.3744611.5992786.635182e-07
0.3762721.5986895.729558e-07
0.3780921.5981084.819553e-07
0.3799211.5975353.905147e-07
0.381.5975113.865600e-07
0.3817591.5969723.494560e-07
0.3836051.5964163.104957e-07
0.3854611.5958692.713470e-07
0.3873251.595332.320089e-07
0.3891991.5947981.924805e-07
0.391.5945741.755700e-07
0.3910811.5942751.667167e-07
0.3929731.5937581.512251e-07
0.3948731.5932491.356586e-07
0.3967831.5927471.200168e-07
0.3987031.5922521.042993e-07
0.41.5919239.367500e-08
0.4006311.5917659.188535e-08
0.4025691.5912838.639091e-08
0.4045161.5908098.086990e-08
0.4064731.5903417.532218e-08
0.4084391.5898796.974763e-08
0.4104151.5894236.414612e-08
0.41241.5889745.851751e-08
0.4143941.5885315.286167e-08
0.4163991.5880934.717848e-08
0.4184131.5876614.146780e-08
0.421.5873273.696800e-08
0.4204371.5872353.669779e-08
0.422471.5868153.543979e-08
0.4245141.58643.417570e-08
0.4265671.585993.290549e-08
0.4286311.5855863.162914e-08
0.4307041.5851873.034662e-08
0.4327871.5847932.905790e-08
0.434881.5844042.776294e-08
0.4369841.584022.646172e-08
0.4390981.5836412.515420e-08
0.441.5834812.459600e-08
0.4412221.5832662.421445e-08
0.4433561.5828962.354785e-08
0.44551.5825312.287802e-08
0.4476551.582172.220494e-08
0.449821.5818142.152862e-08
0.4519961.5814622.084902e-08
0.4541821.5811152.016613e-08
0.4563791.5807711.947995e-08
0.4585871.5804321.879044e-08
0.461.5802181.834900e-08
0.4608051.5800971.838107e-08
0.4630341.5797661.846990e-08
0.4652731.5794381.855915e-08
0.4675241.5791151.864883e-08
0.4697851.5787961.873895e-08
0.4720581.578481.882950e-08
0.4743411.5781681.892049e-08
0.4766351.577861.901192e-08
0.4789411.5775551.910379e-08
0.481.5774171.914600e-08
0.4812571.5772541.869389e-08
0.4835851.5769561.785692e-08
0.4859241.5766621.701591e-08
0.4882751.5763711.617083e-08
0.4906361.5760831.532165e-08
0.493011.5757991.446838e-08
0.4953941.5755181.361097e-08
0.4977911.575241.274942e-08
0.51.5749881.195500e-08
0.5001981.5749661.194234e-08
0.5026181.5746941.178785e-08
0.5050491.5744251.163261e-08
0.5074921.574161.147662e-08
0.5099461.5738971.131988e-08
0.5124131.5736371.116238e-08
0.5148921.5733811.100411e-08
0.5173821.5731271.084508e-08
0.5198851.5728751.068529e-08
0.5223991.5726271.052471e-08
0.5249261.5723811.036337e-08
0.5274651.5721381.020124e-08
0.5300161.5718971.003833e-08
0.532581.5716599.874627e-09
0.5351561.5714249.710135e-09
0.5377451.5711919.544847e-09
0.5403461.5709619.378760e-09
0.5429591.5707339.211869e-09
0.5455861.5705079.044172e-09
0.5482251.5702848.875663e-09
0.551.5701368.762300e-09
0.5508761.5700638.776263e-09
0.5535411.5698458.818714e-09
0.5562181.5696288.861372e-09
0.5589091.5694148.904235e-09
0.5616121.5692038.947306e-09
0.5643291.5689938.990585e-09
0.5670581.5687869.034073e-09
0.5698011.568589.077772e-09
0.5725571.5683779.121682e-09
0.5753271.5681769.165805e-09
0.578111.5679779.210141e-09
0.5809061.567789.254692e-09
0.5837161.5675849.299457e-09
0.5865391.5673919.344440e-09
0.5893761.56729.389640e-09
0.5922271.5670119.435059e-09
0.5950911.5668239.480697e-09
0.597971.5666379.526556e-09
0.61.5665089.558900e-09
0.6008621.5664549.662059e-09
0.6037691.5662711.000978e-08
0.6066891.5660911.035918e-08
0.6096231.5659131.071027e-08
0.6125721.5657361.106307e-08
0.6155351.5655611.141756e-08
0.6185131.5653871.177377e-08
0.6215041.5652161.213171e-08
0.624511.5650461.249137e-08
0.6275311.5648771.285278e-08
0.6305661.564711.321593e-08
0.6336161.5645451.358084e-08
0.6366811.5643811.394752e-08
0.6397611.5642191.431597e-08
0.6428551.5640581.468620e-08
0.6459651.5638991.505822e-08
0.6490891.5637411.543204e-08
0.651.5636951.554100e-08
0.6522291.5635841.534534e-08
0.6553841.5634291.506842e-08
0.6585541.5632761.479015e-08
0.6617391.5631241.451054e-08
0.664941.5629731.422957e-08
0.6681561.5628231.394724e-08
0.6713881.5626751.366355e-08
0.6746361.5625281.337849e-08
0.6778991.5623831.309205e-08
0.6811781.5622381.280422e-08
0.6844731.5620951.251500e-08
0.6877831.5619541.222438e-08
0.691111.5618131.193236e-08
0.6944531.5616741.163892e-08
0.6978121.5615351.134407e-08
0.71.5614461.115200e-08
0.7011871.5613981.109522e-08
0.7045791.5612631.093301e-08
0.7079871.5611281.077002e-08
0.7114111.5609941.060624e-08
0.7148521.5608621.044167e-08
0.718311.560731.027630e-08
0.7217851.56061.011013e-08
0.7252761.5604719.943159e-09
0.7287841.5603439.775380e-09
0.7323091.5602159.606789e-09
0.7358511.5600899.437382e-09
0.739411.5599649.267156e-09
0.7429871.559849.096107e-09
0.7465811.5597178.924230e-09
0.7501921.5595948.751522e-09
0.7538211.5594738.577979e-09
0.7574671.5593538.403596e-09
0.7611311.5592338.228370e-09
0.7648121.5591148.052296e-09
0.7685111.5589977.875370e-09
0.7722291.558887.697589e-09
0.7759641.5587647.518948e-09
0.7797171.5586497.339443e-09
0.7834891.5585357.159069e-09
0.7872781.5584216.977823e-09
0.7910861.5583086.795700e-09
0.7949131.5581976.612697e-09
0.7987581.5580856.428808e-09
0.81.558056.369400e-09
0.8026211.5579756.578288e-09
0.8065041.5578666.887648e-09
0.8104051.5577577.198504e-09
0.8143251.5576497.510864e-09
0.8182631.5575417.824735e-09
0.8222211.5574358.140125e-09
0.8261981.5573298.457039e-09
0.8301951.5572248.775487e-09
0.834211.5571199.095475e-09
0.8382451.5570159.417011e-09
0.84231.5569129.740102e-09
0.8463741.5568091.006476e-08
0.8504681.5567071.039098e-08
0.8545811.5566061.071878e-08
0.8587151.5565051.104817e-08
0.8628691.5564051.137915e-08
0.8670421.5563061.171173e-08
0.8712361.5562071.204592e-08
0.875451.5561081.238173e-08
0.8796851.556011.271916e-08
0.883941.5559131.305822e-08
0.8882151.5558161.339893e-08
0.8925121.555721.374128e-08
0.8968291.5556241.408528e-08
0.91.5555541.433800e-08
0.9011671.5555291.435658e-08
0.9055251.5554341.442602e-08
0.9099051.555341.449579e-08
0.9143071.5552461.456590e-08
0.9187291.5551531.463635e-08
0.9231731.555061.470714e-08
0.9276381.5549681.477828e-08
0.9321251.5548761.484975e-08
0.9366341.5547841.492158e-08
0.9411641.5546931.499375e-08
0.9457171.5546021.506627e-08
0.9502911.5545121.513914e-08
0.9548881.5544221.521236e-08
0.9595061.5543321.528593e-08
0.9641471.5542431.535987e-08
0.9688111.5541541.543416e-08
0.9734971.5540661.550881e-08
0.9782061.5539771.558382e-08
0.9829371.553891.565919e-08
0.9876921.5538021.573493e-08
0.9924691.5537151.581103e-08
0.997271.5536281.588751e-08
11.5535791.593100e-08
1.002091.5535411.596436e-08
1.006941.5534551.604160e-08
1.011811.5533691.611921e-08
1.016711.5532831.619719e-08
1.021621.5531981.627556e-08
1.026561.5531121.635430e-08
1.031531.5530271.643343e-08
1.036521.5529431.651293e-08
1.041531.5528581.659283e-08
1.046571.5527741.667310e-08
1.051631.5526891.675377e-08
1.056721.5526051.683483e-08
1.061831.5525221.691628e-08
1.066971.5524381.699812e-08
1.072131.5523551.708036e-08
1.077311.5522721.716299e-08
1.082521.5521881.724603e-08
1.087761.5521061.732947e-08
1.093021.5520231.741331e-08
1.098311.551941.749755e-08
1.103621.5518571.758221e-08
1.108961.5517751.766727e-08
1.114321.5516931.775275e-08
1.119711.5516111.783863e-08
1.125131.5515281.792494e-08
1.130571.5514461.801166e-08
1.136041.5513641.809880e-08
1.141541.5512821.818636e-08
1.147061.5512011.827435e-08
1.152611.5511191.836276e-08
1.158181.5510371.845160e-08
1.163781.5509551.854087e-08
1.169411.5508731.863057e-08
1.175071.5507921.872070e-08
1.180751.550711.881127e-08
1.186461.5506281.890228e-08
1.19221.5505471.899373e-08
1.197971.5504651.908562e-08
1.21.5504361.911800e-08
1.203761.5503831.980894e-08
1.209591.5503012.087813e-08
1.215441.5502192.195250e-08
1.221311.5501382.303206e-08
1.227221.5500562.411684e-08
1.233161.5499742.520687e-08
1.239121.5498922.630218e-08
1.245121.5498092.740278e-08
1.251141.5497272.850870e-08
1.257191.5496452.961997e-08
1.263271.5495623.073662e-08
1.269381.549483.185867e-08
1.275521.5493973.298615e-08
1.281691.5493143.411908e-08
1.287891.5492313.525749e-08
1.294121.5491483.640141e-08
1.300381.5490653.755086e-08
1.306671.5489813.870587e-08
1.312991.5488973.986646e-08
1.319341.5488144.103268e-08
1.325721.5487294.220453e-08
1.332141.5486454.338205e-08
1.338581.5485614.456526e-08
1.345051.5484764.575420e-08
1.351561.5483914.694889e-08
1.35811.5483064.814936e-08
1.364671.5482214.935563e-08
1.371271.5481355.056774e-08
1.37791.5480495.178571e-08
1.384561.5479635.300958e-08
1.391261.5478775.423936e-08
1.397991.547795.547509e-08
1.41.5477645.584400e-08
1.404751.5477035.664241e-08
1.411551.5476155.778379e-08
1.418381.5475285.893069e-08
1.425241.547446.008313e-08
1.432131.5473526.124115e-08
1.439061.5472636.240478e-08
1.446021.5471746.357402e-08
1.453011.5470856.474893e-08
1.460041.5469956.592952e-08
1.46711.5469056.711582e-08
1.47421.5468146.830785e-08
1.481331.5467236.950566e-08
1.488491.5466327.070925e-08
1.495691.546547.191867e-08
1.502931.5464487.313394e-08
1.51021.5463567.435508e-08
1.51751.5462637.558214e-08
1.524841.5461697.681512e-08
1.532221.5460757.805408e-08
1.539631.5459817.929902e-08
1.547081.5458868.054999e-08
1.554561.5457918.180700e-08
1.562081.5456958.307010e-08
1.569641.5455988.433931e-08
1.577231.5455018.561465e-08
1.584861.5454048.689617e-08
1.592521.5453068.818388e-08
1.61.545218.944000e-08
1.600231.5452078.971454e-08
1.607971.5451089.915218e-08
1.615741.5450091.086355e-07
1.623561.5449081.181646e-07
1.631411.5448081.277399e-07
1.63931.5447061.373614e-07
1.647231.5446041.470295e-07
1.65521.5445011.567444e-07
1.663211.5443981.665063e-07
1.671251.5442941.763153e-07
1.679331.5441891.861719e-07
1.687461.5440841.960761e-07
1.695621.5439782.060282e-07
1.703821.5438712.160284e-07
1.712061.5437642.260770e-07
1.720341.5436562.361742e-07
1.728661.5435472.463203e-07
1.737031.5434382.565154e-07
1.745431.5433272.667599e-07
1.753871.5432162.770539e-07
1.762351.5431052.873977e-07
1.770881.5429922.977915e-07
1.779441.5428793.082356e-07
1.788051.5427643.187302e-07
1.79671.5426493.292756e-07
1.81.5426053.333000e-07
1.805391.5425333.463183e-07
1.814121.5424173.674101e-07
1.82291.5422993.886040e-07
1.831711.5421814.099003e-07
1.840571.5420614.312997e-07
1.849481.5419414.528025e-07
1.858421.541824.744094e-07
1.867411.5416984.961208e-07
1.876441.5415755.179371e-07
1.885521.5414515.398591e-07
1.894641.5413265.618870e-07
1.903811.54125.840215e-07
1.913011.5410736.062631e-07
1.922271.5409466.286122e-07
1.931571.5408176.510695e-07
1.940911.5406876.736354e-07
1.95031.5405566.963104e-07
1.959731.5404247.190951e-07
1.969211.5402917.419900e-07
1.978731.5401577.649956e-07
1.98831.5400217.881126e-07
1.997921.5398858.113413e-07
21.5398558.163600e-07
2.007591.5397478.627801e-07
2.01731.5396099.222012e-07
2.027051.5394699.819097e-07
2.036861.5393281.041907e-06
2.046711.5391851.102194e-06
2.056611.5390421.162774e-06
2.066561.5388971.223646e-06
2.076551.5387511.284812e-06
2.08661.5386041.346275e-06
2.096691.5384561.408034e-06
2.106831.5383061.470093e-06
2.117021.5381551.532451e-06
2.127261.5380021.595112e-06
2.137551.5378491.658075e-06
2.147891.5376941.721343e-06
2.158281.5375371.784917e-06
2.168721.5373791.848798e-06
2.179211.537221.912989e-06
2.189751.5370591.977489e-06
2.21.5369022.040200e-06
2.200341.5368972.041643e-06
2.210991.5367332.086360e-06
2.221681.5365682.131292e-06
2.232431.5364012.176442e-06
2.243231.5362332.221811e-06
2.254081.5360632.267399e-06
2.264981.5358922.313207e-06
2.275931.5357192.359237e-06
2.286941.5355442.405489e-06
2.2981.5353682.451966e-06
2.309121.535192.498667e-06
2.320291.5350112.545594e-06
2.331511.5348292.592748e-06
2.342791.5346462.640130e-06
2.354121.5344622.687741e-06
2.365511.5342752.735583e-06
2.376951.5340872.783655e-06
2.388451.5338972.831961e-06
2.41.5337052.880500e-06

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
—