Optical constants

Refractive index of J-BAK2 (HIKARI)

J-BAK2: n,k 0.365–2.058 µm

Data
formula 3 + tabulated k
Range
0.365–2.058 µm
Temperature
296 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.365–2.058 µm
Refractive index n
1.53996
Extinction coefficient k
1.87414e-08
Permittivity ε1
2.37147
Permittivity ε2
5.77221e-08
Absorption coefficient α
0.00400803 cm⁻¹
Penetration depth δ = λ/(2πk)
4.98998e+09 nm
Abbe number Vd
59.524
Chromatic dispersion dn/dλ
-0.0468579 µm⁻¹
Group index ng
1.56749
Group velocity dispersion
81.9694 fs²/mm
Dispersion parameter D
-447.186 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

# J-BAK2 (HIKARI): J-BAK2
hikari_j_bak2 = ls.fetch_refractiveindex("specs", "HIKARI-optical", "J-BAK2", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(hikari_j_bak2.range_nm)  # (365.015, 2058.09) nm
eps = hikari_j_bak2.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=2.3361606−0.00818245071⁢λ2.0−9.82753897×10-5⁢λ4.0+0.0127499096⁢λ−2.0+0.000122269251⁢λ−4.0+8.48994057×10-6⁢λ−6.0−1.59525058×10-7⁢λ−8.0

Valid from 0.365015 to 2.05809 µm.

Coefficients as stored
CiValue
C12.3361606
C2-0.00818245071
C32.0
C4-9.82753897e-05
C54.0
C60.0127499096
C7-2.0
C80.000122269251
C9-4.0
C108.48994057e-06
C11-6.0
C12-1.59525058e-07
C13-8.0

Comments and conditions

Conditions

temperature
296 K

Properties

thermal dispersion
type: formula A, coefficients: -7.17e-07 1.3367e-08 -3.1142e-12 5.3353e-07 5.8825e-10 0.17288
nd
1.539960
Vd
59.523574
density
value: 2840
thermal expansion
value: 7.6e-06, temperature range: 243 343
dPgF
-0.0008
resistance
phosphate: 2.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 296.0 K): dn/dT = 3.20e-07 K⁻¹ at 633 nm, dn/dT = -1.74e-07 K⁻¹ at 1310 nm, dn/dT = -2.13e-07 K⁻¹ at 1550 nm

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 421 wavelengths, the same grid as the API and the library
J-BAK2 (HIKARI), J-BAK2: n and k versus wavelength
λ (µm)nk
0.3650151.5622853.504958e-08
0.3666011.5619563.331354e-08
0.3681931.561633.156996e-08
0.3697931.5613072.981881e-08
0.371.5612662.959200e-08
0.3713991.5609882.970394e-08
0.3730131.5606722.983302e-08
0.3746331.5603592.996266e-08
0.3762611.560053.009286e-08
0.3778951.5597433.022362e-08
0.3795371.559443.035495e-08
0.381.5593553.039200e-08
0.3811861.559142.937335e-08
0.3828421.5588432.795072e-08
0.3845051.5585492.652190e-08
0.3861751.5582582.508688e-08
0.3878531.557972.364562e-08
0.3895381.5576852.219810e-08
0.391.5576072.180100e-08
0.391231.5574022.068870e-08
0.392931.5571231.915176e-08
0.3946371.5568461.760814e-08
0.3963511.5565721.605781e-08
0.3980731.5563011.450075e-08
0.3998021.5560321.293692e-08
0.41.5560021.275800e-08
0.4015391.5557661.306541e-08
0.4032831.5555031.341385e-08
0.4050351.5552421.376380e-08
0.4067951.5549841.411528e-08
0.4085621.5547291.446828e-08
0.4103371.5544761.482281e-08
0.412121.5542251.517889e-08
0.413911.5539771.553651e-08
0.4157081.5537321.589568e-08
0.4175141.5534891.625642e-08
0.4193281.5532481.661872e-08
0.421.5531591.675300e-08
0.4211491.5530091.700122e-08
0.4229791.5527731.739631e-08
0.4248171.5525391.779312e-08
0.4266621.5523071.819166e-08
0.4285161.5520781.859193e-08
0.4303771.5518511.899393e-08
0.4322471.5516261.939769e-08
0.4341251.5514031.980319e-08
0.436011.5511822.021046e-08
0.4379051.5509632.061950e-08
0.4398071.5507472.103032e-08
0.441.5507252.107200e-08
0.4417181.5505322.115427e-08
0.4436371.550322.124619e-08
0.4455641.5501092.133851e-08
0.4474991.5499012.143122e-08
0.4494431.5496942.152434e-08
0.4513961.549492.161787e-08
0.4533571.5492872.171180e-08
0.4553261.5490872.180613e-08
0.4573041.5488882.190088e-08
0.4592911.5486912.199604e-08
0.461.5486212.203000e-08
0.4612861.5484952.184451e-08
0.463291.5483022.155554e-08
0.4653031.548112.126532e-08
0.4673241.5479212.097383e-08
0.4693541.5477332.068108e-08
0.4713931.5475462.038706e-08
0.4734411.5473622.009176e-08
0.4754981.5471791.979518e-08
0.4775641.5469971.949731e-08
0.4796381.5468181.919815e-08
0.481.5467871.914600e-08
0.4817221.546641.887056e-08
0.4838151.5464631.853583e-08
0.4859171.5462891.819965e-08
0.4880271.5461151.786200e-08
0.4901481.5459441.752289e-08
0.4922771.5457741.718231e-08
0.4944151.5456051.684025e-08
0.4965631.5454381.649670e-08
0.4987211.5452731.615165e-08
0.51.5451751.594700e-08
0.5008871.5451091.597530e-08
0.5030631.5449461.604471e-08
0.5052481.5447851.611443e-08
0.5074431.5446251.618444e-08
0.5096481.5444671.625477e-08
0.5118621.544311.632539e-08
0.5140861.5441541.639633e-08
0.5163191.5441.646757e-08
0.5185621.5438471.653912e-08
0.5208151.5436961.661099e-08
0.5230771.5435451.668316e-08
0.5253491.5433971.675565e-08
0.5276321.5432491.682845e-08
0.5299241.5431031.690157e-08
0.5322261.5429581.697501e-08
0.5345381.5428141.704877e-08
0.536861.5426711.712284e-08
0.5391931.542531.719724e-08
0.5415351.542391.727196e-08
0.5438871.5422511.734701e-08
0.546251.5421131.742238e-08
0.5486231.5419761.749808e-08
0.551.5418981.754200e-08
0.5510071.5418411.757411e-08
0.55341.5417061.765047e-08
0.5558041.5415731.772716e-08
0.5582191.5414411.780419e-08
0.5606441.541311.788154e-08
0.563081.541181.795924e-08
0.5655261.5410511.803727e-08
0.5679821.5409241.811564e-08
0.570451.5407971.819435e-08
0.5729281.5406711.827341e-08
0.5754171.5405471.835280e-08
0.5779171.5404231.843255e-08
0.5804271.54031.851263e-08
0.5829491.5401791.859307e-08
0.5854811.5400581.867386e-08
0.5880251.5399381.875499e-08
0.5905791.539821.883648e-08
0.5931451.5397021.891832e-08
0.5957221.5395851.900052e-08
0.598311.5394691.908308e-08
0.61.5393941.913700e-08
0.6009091.5393541.926045e-08
0.6035191.539241.961500e-08
0.6061411.5391271.997110e-08
0.6087741.5390152.032874e-08
0.6114191.5389032.068794e-08
0.6140751.5387932.104870e-08
0.6167431.5386832.141102e-08
0.6194221.5385742.177492e-08
0.6221131.5384662.214040e-08
0.6248161.5383592.250747e-08
0.627531.5382532.287613e-08
0.6302561.5381472.324640e-08
0.6329941.5380422.361827e-08
0.6357441.5379382.399176e-08
0.6385061.5378352.436687e-08
0.641281.5377332.474361e-08
0.6440661.5376312.512199e-08
0.6468641.537532.550201e-08
0.6496741.537432.588368e-08
0.651.5374192.592800e-08
0.6524961.5373312.602754e-08
0.6553311.5372322.614058e-08
0.6581781.5371342.625412e-08
0.6610371.5370372.636815e-08
0.6639081.536942.648267e-08
0.6667931.5368442.659769e-08
0.6696891.5367492.671321e-08
0.6725991.5366552.682923e-08
0.6755211.5365612.694576e-08
0.6784551.5364682.706279e-08
0.6814031.5363752.718033e-08
0.6843631.5362832.729839e-08
0.6873361.5361922.741695e-08
0.6903221.5361012.753603e-08
0.6933211.5360112.765563e-08
0.6963331.5359222.777574e-08
0.6993581.5358332.789638e-08
0.71.5358152.792200e-08
0.7023961.5357452.847811e-08
0.7054471.5356582.918639e-08
0.7085121.5355712.989775e-08
0.711591.5354843.061221e-08
0.7146811.5353983.132976e-08
0.7177861.5353133.205043e-08
0.7209041.5352283.277424e-08
0.7240361.5351443.350118e-08
0.7271811.535063.423129e-08
0.730341.5349773.496457e-08
0.7335131.5348953.570103e-08
0.73671.5348133.644069e-08
0.73991.5347313.718357e-08
0.7431141.534653.792967e-08
0.7463421.5345693.867902e-08
0.7495851.5344893.943162e-08
0.7528411.534414.018748e-08
0.7561121.5343314.094664e-08
0.7593961.5342524.170909e-08
0.7626951.5341744.247485e-08
0.7660091.5340964.324394e-08
0.7693361.5340194.401637e-08
0.7726791.5339424.479216e-08
0.7760351.5338654.557131e-08
0.7794071.5337894.635386e-08
0.7827931.5337144.713980e-08
0.7861931.5336394.792915e-08
0.7896091.5335644.872194e-08
0.7930391.533494.951816e-08
0.7964841.5334165.031785e-08
0.7999441.5333425.112101e-08
0.81.5333415.113400e-08
0.8034191.5332695.036711e-08
0.8069091.5331974.958428e-08
0.8104151.5331244.879806e-08
0.8139351.5330524.800841e-08
0.8174711.5329814.721534e-08
0.8210231.5329094.641882e-08
0.8245891.5328384.561884e-08
0.8281721.5327684.481539e-08
0.8317691.5326984.400845e-08
0.8353831.5326284.319800e-08
0.8390121.5325584.238403e-08
0.8426571.5324894.156652e-08
0.8463171.532424.074546e-08
0.8499941.5323513.992084e-08
0.8536871.5322833.909263e-08
0.8573951.5322153.826082e-08
0.861121.5321473.742541e-08
0.8648611.532083.658636e-08
0.8686181.5320133.574367e-08
0.8723911.5319463.489731e-08
0.8761811.531883.404728e-08
0.8799881.5318133.319356e-08
0.8838111.5317473.233613e-08
0.887651.5316813.147497e-08
0.8915061.5316163.061007e-08
0.8953791.5315512.974142e-08
0.8992691.5314862.886899e-08
0.91.5314732.870500e-08
0.9031751.5314212.880630e-08
0.9070991.5313562.893146e-08
0.911041.5312922.905717e-08
0.9149981.5312282.918342e-08
0.9189721.5311642.931022e-08
0.9229651.53112.943757e-08
0.9269741.5310372.956548e-08
0.9310011.5309732.969394e-08
0.9350461.530912.982296e-08
0.9391081.5308482.995254e-08
0.9431881.5307853.008268e-08
0.9472851.5307223.021339e-08
0.95141.530663.034467e-08
0.9555331.5305983.047651e-08
0.9596841.5305363.060893e-08
0.9638531.5304743.074193e-08
0.9680411.5304123.087550e-08
0.9722461.5303513.100965e-08
0.976471.5302893.114438e-08
0.9807121.5302283.127970e-08
0.9849721.5301673.141561e-08
0.9892511.5301063.155211e-08
0.9935491.5300453.168920e-08
0.9978651.5299843.182689e-08
11.5299543.189500e-08
1.00221.5299243.196516e-08
1.006551.5298633.210403e-08
1.010931.5298033.224349e-08
1.015321.5297423.238357e-08
1.019731.5296823.252425e-08
1.024161.5296223.266554e-08
1.028611.5295623.280745e-08
1.033081.5295023.294997e-08
1.037561.5294423.309312e-08
1.042071.5293823.323688e-08
1.04661.5293233.338127e-08
1.051151.5292633.352628e-08
1.055711.5292033.367193e-08
1.06031.5291443.381821e-08
1.06491.5290843.396512e-08
1.069531.5290253.411268e-08
1.074181.5289653.426087e-08
1.078841.5289063.440971e-08
1.083531.5288473.455919e-08
1.088241.5287873.470932e-08
1.092961.5287283.486011e-08
1.097711.5286693.501155e-08
1.102481.528613.516365e-08
1.107271.528553.531641e-08
1.112081.5284913.546983e-08
1.116911.5284323.562392e-08
1.121761.5283723.577868e-08
1.126641.5283133.593411e-08
1.131531.5282543.609021e-08
1.136451.5281943.624700e-08
1.141381.5281353.640446e-08
1.146341.5280763.656261e-08
1.151321.5280163.672145e-08
1.156321.5279573.688098e-08
1.161351.5278973.704120e-08
1.166391.5278383.720211e-08
1.171461.5277783.736373e-08
1.176551.5277183.752604e-08
1.181661.5276593.768907e-08
1.186791.5275993.785280e-08
1.191951.5275393.801724e-08
1.197131.5274793.818239e-08
1.21.5274463.827400e-08
1.202331.5274193.913199e-08
1.207551.5273594.105663e-08
1.21281.5272984.298964e-08
1.218071.5272384.493104e-08
1.223361.5271774.688088e-08
1.228671.5271174.883918e-08
1.234011.5270565.080600e-08
1.239371.5269955.278135e-08
1.244751.5269345.476529e-08
1.250161.5268735.675785e-08
1.255591.5268125.875907e-08
1.261051.5267516.076897e-08
1.266531.5266896.278761e-08
1.272031.5266286.481502e-08
1.277551.5265666.685124e-08
1.28311.5265046.889630e-08
1.288681.5264427.095025e-08
1.294281.526387.301312e-08
1.29991.5263177.508495e-08
1.305551.5262547.716578e-08
1.311221.5261927.925565e-08
1.316911.5261298.135460e-08
1.322641.5260658.346267e-08
1.328381.5260028.557989e-08
1.334151.5259388.770632e-08
1.339951.5258758.984198e-08
1.345771.525819.198692e-08
1.351621.5257469.414118e-08
1.357491.5256829.630479e-08
1.363381.5256179.847781e-08
1.369311.5255521.006603e-07
1.375261.5254871.028522e-07
1.381231.5254211.050537e-07
1.387231.5253561.072647e-07
1.393261.525291.094853e-07
1.399311.5252231.117156e-07
1.41.5252161.119700e-07
1.405391.5251571.124008e-07
1.411491.525091.128889e-07
1.417631.5250231.133792e-07
1.423781.5249561.138715e-07
1.429971.5248881.143661e-07
1.436181.524821.148627e-07
1.442421.5247521.153615e-07
1.448691.5246831.158625e-07
1.454981.5246141.163657e-07
1.46131.5245451.168710e-07
1.467651.5244761.173786e-07
1.474031.5244061.178883e-07
1.480431.5243361.184003e-07
1.486861.5242651.189145e-07
1.493321.5241941.194309e-07
1.499811.5241231.199495e-07
1.506321.5240511.204704e-07
1.512871.5239791.209936e-07
1.519441.5239071.215191e-07
1.526041.5238341.220468e-07
1.532671.5237611.225768e-07
1.539331.5236871.231092e-07
1.546011.5236141.236438e-07
1.552731.5235391.241808e-07
1.559481.5234641.247201e-07
1.566251.5233891.252617e-07
1.573051.5233141.258057e-07
1.579891.5232381.263521e-07
1.586751.5231611.269008e-07
1.593641.5230841.274519e-07
1.61.5230131.279600e-07
1.600571.5230071.287518e-07
1.607521.5229291.384456e-07
1.61451.5228511.481816e-07
1.621521.5227721.579599e-07
1.628561.5226931.677806e-07
1.635641.5226131.776440e-07
1.642741.5225331.875503e-07
1.649881.5224521.974996e-07
1.657051.5223712.074921e-07
1.664251.5222892.175280e-07
1.671481.5222072.276076e-07
1.678741.5221242.377309e-07
1.686031.522042.478982e-07
1.693351.5219562.581096e-07
1.700711.5218722.683655e-07
1.70811.5217872.786658e-07
1.715521.5217012.890110e-07
1.722971.5216152.994010e-07
1.730461.5215283.098362e-07
1.737971.5214413.203168e-07
1.745521.5213533.308428e-07
1.753111.5212653.414146e-07
1.760721.5211763.520323e-07
1.768371.5210863.626962e-07
1.776051.5209953.734063e-07
1.783771.5209043.841630e-07
1.791521.5208133.949665e-07
1.79931.520724.058168e-07
1.81.5207124.067900e-07
1.807121.5206274.231595e-07
1.814971.5205344.412122e-07
1.822851.5204394.593433e-07
1.830771.5203444.775533e-07
1.838731.5202484.958423e-07
1.846711.5201525.142107e-07
1.854741.5200555.326590e-07
1.862791.5199575.511874e-07
1.870891.5198585.697963e-07
1.879011.5197595.884861e-07
1.887181.5196596.072570e-07
1.895371.5195586.261095e-07
1.903611.5194566.450439e-07
1.911881.5193546.640605e-07
1.920181.5192516.831598e-07
1.928531.5191467.023420e-07
1.93691.5190427.216076e-07
1.945321.5189367.409568e-07
1.953771.518837.603901e-07
1.962261.5187227.799079e-07
1.970781.5186147.995104e-07
1.979341.5185058.191981e-07
1.987941.5183958.389713e-07
1.996581.5182848.588304e-07
21.518248.667000e-07
2.005251.5181738.975123e-07
2.013961.518069.486258e-07
2.022711.5179479.999613e-07
2.03151.5178321.051520e-06
2.040321.5177171.103302e-06
2.049191.5176011.155310e-06
2.058091.5174831.207543e-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
—