Optical constants

Refractive index of SK4 (HIKARI)

SK4: n,k 0.4–0.7 µm

Data
formula 3 + tabulated k
Range
0.4–0.7 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.4–0.7 µm
Refractive index n
1.61272
Extinction coefficient k
4.67830e-09
Permittivity ε1
2.60086
Permittivity ε2
1.50895e-08
Absorption coefficient α
0.0010005 cm⁻¹
Penetration depth δ = λ/(2πk)
1.99901e+10 nm
Abbe number Vd
58.473
Chromatic dispersion dn/dλ
-0.0541741 µm⁻¹
Group index ng
1.64455
Group velocity dispersion
96.1176 fs²/mm
Dispersion parameter D
-524.372 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

# SK4 (HIKARI): SK4
hikari_sk4 = ls.fetch_refractiveindex("specs", "HIKARI-optical", "SK4", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(hikari_sk4.range_nm)  # (400, 700) nm
eps = hikari_sk4.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

Polynomial (formula 3), λ in µm
n2=2.542124+0.002965422⁢λ2.0+0.02316274⁢λ−2.0−0.001681083⁢λ−4.0+0.0002235719⁢λ−6.0−1.000551×10-5⁢λ−8.0

Valid from 0.4 to 0.7 µm.

Coefficients as stored
CiValue
C12.542124
C20.002965422
C32.0
C40.02316274
C5-2.0
C6-0.001681083
C7-4.0
C80.0002235719
C9-6.0
C10-1.000551e-05
C11-8.0

Comments and conditions

Conditions

temperature
293 K

Properties

nd
1.612720
Vd
58.472693
glass code
613585
glass status
preferred
density
value: 3500
thermal expansion
value: 7e-06, temperature range: 243 343
dPgF
-0.0023

References

Cite

NIKON Zemax catalog 2017-11 (obtained from http://www.nikon.com); See also HIKARI 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 408 wavelengths, the same grid as the API and the library
SK4 (HIKARI), SK4: n and k versus wavelength
λ (µm)nk
0.41.6312614.487800e-08
0.4005611.6311624.446643e-08
0.4011241.6310634.405428e-08
0.4016871.6309654.364155e-08
0.402251.6308664.322825e-08
0.4028151.6307684.281436e-08
0.403381.630674.239989e-08
0.4039461.6305734.198484e-08
0.4045131.6304764.156921e-08
0.4050811.6303794.115300e-08
0.405651.6302824.073620e-08
0.4062191.6301864.031881e-08
0.4067891.630093.990084e-08
0.407361.6299953.948229e-08
0.4079321.6298993.906314e-08
0.4085041.6298043.864341e-08
0.4090781.6297093.822309e-08
0.4096521.6296153.780218e-08
0.4102271.6295213.738067e-08
0.4108031.6294273.695858e-08
0.4113791.6293333.653589e-08
0.4119571.629243.611261e-08
0.4125351.6291473.568874e-08
0.4131141.6290543.526427e-08
0.4136941.6289623.483921e-08
0.4142741.628873.441355e-08
0.4148561.6287783.398729e-08
0.4154381.6286863.356043e-08
0.4160211.6285953.313298e-08
0.4166051.6285043.270492e-08
0.417191.6284133.227627e-08
0.4177751.6283233.184701e-08
0.4183621.6282333.141715e-08
0.4189491.6281433.098668e-08
0.4195371.6280533.055561e-08
0.421.6279833.021600e-08
0.4201261.6279643.020287e-08
0.4207151.6278753.014119e-08
0.4213061.6277863.007942e-08
0.4218971.6276973.001757e-08
0.4224891.6276092.995563e-08
0.4230821.6275212.989361e-08
0.4236761.6274342.983149e-08
0.4242711.6273462.976929e-08
0.4248661.6272592.970701e-08
0.4254621.6271722.964463e-08
0.426061.6270862.958217e-08
0.4266581.6269992.951962e-08
0.4272561.6269132.945699e-08
0.4278561.6268272.939426e-08
0.4284571.6267422.933145e-08
0.4290581.6266572.926855e-08
0.429661.6265722.920556e-08
0.4302631.6264872.914248e-08
0.4308671.6264022.907931e-08
0.4314721.6263182.901606e-08
0.4320771.6262342.895271e-08
0.4326841.6261512.888928e-08
0.4332911.6260672.882576e-08
0.4338991.6259842.876215e-08
0.4345081.6259012.869845e-08
0.4351181.6258182.863466e-08
0.4357291.6257362.857078e-08
0.436341.6256542.850681e-08
0.4369531.6255722.844275e-08
0.4375661.625492.837860e-08
0.438181.6254092.831436e-08
0.4387951.6253282.825003e-08
0.4394111.6252472.818561e-08
0.441.625172.812400e-08
0.4400281.6251662.811556e-08
0.4406451.6250862.792738e-08
0.4412641.6250062.773894e-08
0.4418831.6249262.755023e-08
0.4425031.6248462.736125e-08
0.4431241.6247672.717202e-08
0.4437461.6246882.698251e-08
0.4443691.6246092.679274e-08
0.4449931.624532.660270e-08
0.4456171.6244522.641240e-08
0.4462431.6243732.622183e-08
0.4468691.6242952.603099e-08
0.4474961.6242182.583988e-08
0.4481241.624142.564851e-08
0.4487531.6240632.545687e-08
0.4493831.6239862.526496e-08
0.4500141.6239092.507277e-08
0.4506451.6238332.488032e-08
0.4512781.6237562.468760e-08
0.4519111.623682.449461e-08
0.4525461.6236042.430135e-08
0.4531811.6235292.410782e-08
0.4538171.6234532.391401e-08
0.4544541.6233782.371993e-08
0.4550921.6233032.352558e-08
0.455731.6232292.333096e-08
0.456371.6231542.313606e-08
0.4570111.623082.294090e-08
0.4576521.6230062.274545e-08
0.4582941.6229322.254974e-08
0.4589381.6228592.235374e-08
0.4595821.6227852.215748e-08
0.461.6227382.203000e-08
0.4602271.6227122.191039e-08
0.4608731.6226392.156952e-08
0.4615191.6225662.122818e-08
0.4621671.6224942.088636e-08
0.4628161.6224222.054406e-08
0.4634651.622352.020128e-08
0.4641161.6222781.985802e-08
0.4647671.6222061.951427e-08
0.465421.6221351.917004e-08
0.4660731.6220641.882533e-08
0.4667271.6219931.848014e-08
0.4673821.6219221.813446e-08
0.4680381.6218511.778830e-08
0.4686951.6217811.744165e-08
0.4693531.6217111.709452e-08
0.4700121.6216411.674689e-08
0.4706711.6215711.639878e-08
0.4713321.6215021.605018e-08
0.4719931.6214331.570109e-08
0.4726561.6213631.535152e-08
0.4733191.6212951.500145e-08
0.4739841.6212261.465089e-08
0.4746491.6211571.429983e-08
0.4753151.6210891.394829e-08
0.4759821.6210211.359625e-08
0.476651.6209531.324372e-08
0.4773191.6208861.289069e-08
0.4779891.6208181.253717e-08
0.478661.6207511.218315e-08
0.4793321.6206841.182863e-08
0.481.6206171.147600e-08
0.4800051.6206171.147521e-08
0.4806781.620551.135696e-08
0.4813531.6204841.123855e-08
0.4820281.6204181.111998e-08
0.4827051.6203511.100123e-08
0.4833821.6202861.088232e-08
0.4840611.620221.076325e-08
0.484741.6201541.064400e-08
0.4854211.6200891.052459e-08
0.4861021.6200241.040501e-08
0.4867841.6199591.028527e-08
0.4874671.6198941.016535e-08
0.4881521.619831.004527e-08
0.4888371.6197659.925017e-09
0.4895231.6197019.804596e-09
0.490211.6196379.684007e-09
0.4908981.6195739.563249e-09
0.4915871.619519.442320e-09
0.4922771.6194469.321223e-09
0.4929681.6193839.199955e-09
0.493661.619329.078517e-09
0.4943531.6192578.956909e-09
0.4950461.6191948.835130e-09
0.4957411.6191328.713180e-09
0.4964371.619078.591058e-09
0.4971341.6190078.468766e-09
0.4978321.6189458.346302e-09
0.498531.6188848.223665e-09
0.499231.6188228.100857e-09
0.4999311.6187617.977877e-09
0.51.6187557.965700e-09
0.5006321.6186997.920343e-09
0.5013351.6186387.869939e-09
0.5020391.6185777.819464e-09
0.5027431.6185177.768919e-09
0.5034491.6184567.718302e-09
0.5041551.6183967.667615e-09
0.5048631.6183357.616856e-09
0.5055721.6182757.566026e-09
0.5062811.6182157.515124e-09
0.5069921.6181567.464152e-09
0.5077031.6180967.413107e-09
0.5084161.6180377.361991e-09
0.509131.6179787.310803e-09
0.5098441.6179197.259544e-09
0.510561.617867.208212e-09
0.5112761.6178017.156809e-09
0.5119941.6177437.105333e-09
0.5127121.6176847.053785e-09
0.5134321.6176267.002165e-09
0.5141531.6175686.950472e-09
0.5148741.617516.898707e-09
0.5155971.6174526.846869e-09
0.5163211.6173956.794958e-09
0.5170451.6173376.742975e-09
0.5177711.617286.690918e-09
0.5184981.6172236.638788e-09
0.5192251.6171666.586586e-09
0.5199541.617116.534310e-09
0.5206841.6170536.481960e-09
0.5214151.6169976.429537e-09
0.5221471.616946.377041e-09
0.5228791.6168846.324471e-09
0.5236131.6168286.271827e-09
0.5243481.6167726.219109e-09
0.5250841.6167176.166317e-09
0.5258211.6166616.113451e-09
0.5265591.6166066.060511e-09
0.5272981.6165516.007497e-09
0.5280381.6164965.954408e-09
0.5287791.6164415.901245e-09
0.5295211.6163865.848007e-09
0.5302651.6163325.794694e-09
0.5310091.6162775.741307e-09
0.5317541.6162235.687844e-09
0.5325011.6161695.634307e-09
0.5332481.6161155.580694e-09
0.5339961.6160615.527006e-09
0.5347461.6160075.473243e-09
0.5354961.6159545.419405e-09
0.5362481.6159015.365490e-09
0.5370011.6158475.311500e-09
0.5377541.6157945.257435e-09
0.5385091.6157415.203293e-09
0.5392651.6156895.149076e-09
0.5400221.6156365.094782e-09
0.540781.6155845.040412e-09
0.5415391.6155314.985966e-09
0.5422991.6154794.931444e-09
0.543061.6154274.876845e-09
0.5438221.6153754.822169e-09
0.5445851.6153234.767416e-09
0.545351.6152724.712587e-09
0.5461151.615224.657681e-09
0.5468821.6151694.602698e-09
0.5476491.6151184.547637e-09
0.5484181.6150674.492499e-09
0.5491871.6150164.437284e-09
0.5499581.6149654.381992e-09
0.551.6149624.379000e-09
0.550731.6149144.384812e-09
0.5515031.6148644.390965e-09
0.5522771.6148134.397126e-09
0.5530521.6147634.403297e-09
0.5538291.6147134.409475e-09
0.5546061.6146634.415663e-09
0.5553841.6146134.421859e-09
0.5561641.6145644.428064e-09
0.5569441.6145144.434277e-09
0.5577261.6144654.440499e-09
0.5585091.6144154.446730e-09
0.5592931.6143664.452970e-09
0.5600781.6143174.459219e-09
0.5608641.6142684.465476e-09
0.5616511.614224.471742e-09
0.5624391.6141714.478017e-09
0.5632291.6141224.484300e-09
0.5640191.6140744.490593e-09
0.5648111.6140264.496894e-09
0.5656041.6139784.503204e-09
0.5663971.613934.509523e-09
0.5671921.6138824.515851e-09
0.5679881.6138344.522188e-09
0.5687861.6137874.528533e-09
0.5695841.6137394.534888e-09
0.5703831.6136924.541251e-09
0.5711841.6136454.547624e-09
0.5719861.6135984.554005e-09
0.5727881.6135514.560395e-09
0.5735921.6135044.566795e-09
0.5743971.6134574.573203e-09
0.5752041.6134114.579620e-09
0.5760111.6133644.586046e-09
0.5768191.6133184.592481e-09
0.5776291.6132724.598926e-09
0.578441.6132264.605379e-09
0.5792511.613184.611841e-09
0.5800641.6131344.618313e-09
0.5808791.6130884.624793e-09
0.5816941.6130434.631283e-09
0.582511.6129974.637782e-09
0.5833281.6129524.644290e-09
0.5841471.6129074.650807e-09
0.5849661.6128624.657333e-09
0.5857871.6128174.663868e-09
0.586611.6127724.670413e-09
0.5874331.6127274.676966e-09
0.5882571.6126824.683529e-09
0.5890831.6126384.690101e-09
0.589911.6125944.696682e-09
0.5907381.6125494.703273e-09
0.5915671.6125054.709873e-09
0.5923971.6124614.716482e-09
0.5932291.6124174.723100e-09
0.5940611.6123734.729728e-09
0.5948951.612334.736365e-09
0.595731.6122864.743011e-09
0.5965661.6122434.749666e-09
0.5974031.6121994.756331e-09
0.5982421.6121564.763006e-09
0.5990821.6121134.769689e-09
0.5999221.612074.776382e-09
0.61.6120664.777000e-09
0.6007641.6120274.783086e-09
0.6016081.6119854.789800e-09
0.6024521.6119424.796523e-09
0.6032981.6118994.803255e-09
0.6041441.6118574.809997e-09
0.6049921.6118154.816748e-09
0.6058411.6117724.823509e-09
0.6066921.611734.830279e-09
0.6075431.6116884.837059e-09
0.6083961.6116474.843848e-09
0.609251.6116054.850647e-09
0.6101051.6115634.857455e-09
0.6109611.6115224.864273e-09
0.6118191.611484.871100e-09
0.6126771.6114394.877937e-09
0.6135371.6113984.884784e-09
0.6143981.6113574.891640e-09
0.6152611.6113164.898506e-09
0.6161241.6112754.905381e-09
0.6169891.6112344.912266e-09
0.6178551.6111934.919161e-09
0.6187221.6111534.926066e-09
0.6195911.6111124.932980e-09
0.620461.6110724.939904e-09
0.6213311.6110324.946837e-09
0.6222031.6109924.953781e-09
0.6230761.6109524.960734e-09
0.6239511.6109124.967697e-09
0.6248271.6108724.974669e-09
0.6257041.6108324.981652e-09
0.6265821.6107934.988644e-09
0.6274611.6107534.995646e-09
0.6283421.6107145.002658e-09
0.6292241.6106745.009679e-09
0.6301071.6106355.016711e-09
0.6309911.6105965.023752e-09
0.6318771.6105575.030803e-09
0.6327641.6105185.037865e-09
0.6336521.610485.044936e-09
0.6345411.6104415.052017e-09
0.6354321.6104025.059108e-09
0.6363241.6103645.066208e-09
0.6372171.6103255.073319e-09
0.6381111.6102875.080440e-09
0.6390071.6102495.087571e-09
0.6399041.6102115.094712e-09
0.6408021.6101735.101863e-09
0.6417011.6101355.109024e-09
0.6426021.6100975.116194e-09
0.6435041.610065.123375e-09
0.6444071.6100225.130567e-09
0.6453111.6099855.137768e-09
0.6462171.6099475.144979e-09
0.6471241.609915.152200e-09
0.6480321.6098735.159432e-09
0.6489421.6098365.166674e-09
0.6498521.6097995.173926e-09
0.651.6097935.175100e-09
0.6507651.6097625.181188e-09
0.6516781.6097255.188460e-09
0.6525931.6096885.195742e-09
0.6535091.6096525.203035e-09
0.6544261.6096155.210338e-09
0.6553441.6095795.217651e-09
0.6562641.6095435.224974e-09
0.6571851.6095065.232308e-09
0.6581081.609475.239652e-09
0.6590311.6094345.247006e-09
0.6599561.6093985.254371e-09
0.6608821.6093625.261746e-09
0.661811.6093275.269131e-09
0.6627391.6092915.276527e-09
0.6636691.6092565.283933e-09
0.6646011.609225.291349e-09
0.6655331.6091855.298776e-09
0.6664671.6091495.306213e-09
0.6674031.6091145.313661e-09
0.668341.6090795.321119e-09
0.6692781.6090445.328588e-09
0.6702171.6090095.336067e-09
0.6711581.6089745.343557e-09
0.67211.608945.351057e-09
0.6730431.6089055.358567e-09
0.6739881.6088715.366089e-09
0.6749331.6088365.373620e-09
0.6758811.6088025.381163e-09
0.6768291.6087685.388716e-09
0.6777791.6087335.396279e-09
0.6787311.6086995.403853e-09
0.6796831.6086655.411438e-09
0.6806371.6086315.419033e-09
0.6815921.6085985.426639e-09
0.6825491.6085645.434256e-09
0.6835071.608535.441884e-09
0.6844661.6084975.449522e-09
0.6854271.6084635.457171e-09
0.6863891.608435.464830e-09
0.6873521.6083975.472500e-09
0.6883171.6083635.480182e-09
0.6892831.608335.487873e-09
0.6902511.6082975.495576e-09
0.6912191.6082645.503290e-09
0.692191.6082315.511014e-09
0.6931611.6081995.518749e-09
0.6941341.6081665.526495e-09
0.6951081.6081335.534252e-09
0.6960841.6081015.542020e-09
0.6970611.6080685.549798e-09
0.6980391.6080365.557588e-09
0.6990191.6080045.565389e-09
0.71.6079725.573200e-09

Optical transmission calculator

Free-standing sample in vacuum, normal incidence
Method
Transmittance T
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Reflectance R
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Fresnel reflection calculator

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