Optical constants

Refractive index of BAF4 (HIKARI)

BAF4: 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
1.60562
Extinction coefficient k
8.27428e-09
Permittivity ε1
2.57801
Permittivity ε2
2.65707e-08
Absorption coefficient α
0.00176953 cm⁻¹
Penetration depth δ = λ/(2πk)
1.13024e+10 nm
Abbe number Vd
43.768
Chromatic dispersion dn/dλ
-0.0706014 µm⁻¹
Group index ng
1.6471
Group velocity dispersion
133.278 fs²/mm
Dispersion parameter D
-727.104 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

# BAF4 (HIKARI): BAF4
hikari_baf4 = ls.fetch_refractiveindex("specs", "HIKARI-optical", "BAF4", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(hikari_baf4.range_nm)  # (400, 700) nm
eps = hikari_baf4.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=2.504959+0.003324741⁢λ2.0+0.02831428⁢λ−2.0−0.002044138⁢λ−4.0+0.0003343099⁢λ−6.0−1.534858×10-5⁢λ−8.0

Valid from 0.4 to 0.7 µm.

Coefficients as stored
CiValue
C12.504959
C20.003324741
C32.0
C40.02831428
C5-2.0
C6-0.002044138
C7-4.0
C80.0003343099
C9-6.0
C10-1.534858e-05
C11-8.0

Comments and conditions

Conditions

temperature
293 K

Properties

nd
1.605620
Vd
43.767629
glass code
606438
glass status
preferred
density
value: 3370
thermal expansion
value: 7.8e-06, temperature range: 243 343
dPgF
0.0009

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
BAF4 (HIKARI), BAF4: n and k versus wavelength
λ (µm)nk
0.41.6311979.039800e-08
0.4005611.6310538.918322e-08
0.4011241.630918.796673e-08
0.4016871.6307668.674853e-08
0.402251.6306248.552863e-08
0.4028151.6304828.430701e-08
0.403381.630348.308368e-08
0.4039461.6301998.185863e-08
0.4045131.6300598.063186e-08
0.4050811.6299197.940337e-08
0.405651.6297797.817316e-08
0.4062191.629647.694122e-08
0.4067891.6295017.570754e-08
0.407361.6293637.447214e-08
0.4079321.6292267.323501e-08
0.4085041.6290897.199614e-08
0.4090781.6289527.075552e-08
0.4096521.6288166.951317e-08
0.4102271.628686.826908e-08
0.4108031.6285456.702324e-08
0.4113791.628416.577565e-08
0.4119571.6282766.452630e-08
0.4125351.6281426.327521e-08
0.4131141.6280096.202236e-08
0.4136941.6278766.076775e-08
0.4142741.6277445.951138e-08
0.4148561.6276125.825325e-08
0.4154381.6274815.699335e-08
0.4160211.627355.573168e-08
0.4166051.627225.446824e-08
0.417191.627095.320303e-08
0.4177751.626965.193604e-08
0.4183621.6268315.066728e-08
0.4189491.6267034.939673e-08
0.4195371.6265754.812440e-08
0.421.6264744.712200e-08
0.4201261.6264474.700272e-08
0.4207151.626324.644260e-08
0.4213061.6261934.588170e-08
0.4218971.6260674.532001e-08
0.4224891.6259414.475753e-08
0.4230821.6258164.419426e-08
0.4236761.6256914.363020e-08
0.4242711.6255664.306535e-08
0.4248661.6254424.249971e-08
0.4254621.6253194.193327e-08
0.426061.6251964.136604e-08
0.4266581.6250734.079801e-08
0.4272561.6249514.022919e-08
0.4278561.6248293.965956e-08
0.4284571.6247083.908914e-08
0.4290581.6245873.851792e-08
0.429661.6244663.794589e-08
0.4302631.6243463.737306e-08
0.4308671.6242263.679943e-08
0.4314721.6241073.622499e-08
0.4320771.6239883.564975e-08
0.4326841.623873.507370e-08
0.4332911.6237523.449684e-08
0.4338991.6236343.391917e-08
0.4345081.6235173.334069e-08
0.4351181.62343.276140e-08
0.4357291.6232843.218129e-08
0.436341.6231683.160037e-08
0.4369531.6230533.101864e-08
0.4375661.6229383.043609e-08
0.438181.6228232.985272e-08
0.4387951.6227092.926853e-08
0.4394111.6225952.868352e-08
0.441.6224862.812400e-08
0.4400281.6224812.811046e-08
0.4406451.6223682.780862e-08
0.4412641.6222562.750635e-08
0.4418831.6221432.720365e-08
0.4425031.6220312.690053e-08
0.4431241.621922.659698e-08
0.4437461.6218092.629301e-08
0.4443691.6216982.598861e-08
0.4449931.6215882.568378e-08
0.4456171.6214782.537853e-08
0.4462431.6213682.507285e-08
0.4468691.6212592.476674e-08
0.4474961.6211512.446020e-08
0.4481241.6210422.415322e-08
0.4487531.6209342.384582e-08
0.4493831.6208272.353799e-08
0.4500141.6207192.322972e-08
0.4506451.6206122.292102e-08
0.4512781.6205062.261189e-08
0.4519111.62042.230233e-08
0.4525461.6202942.199233e-08
0.4531811.6201892.168189e-08
0.4538171.6200842.137102e-08
0.4544541.6199792.105971e-08
0.4550921.6198752.074797e-08
0.455731.6197712.043579e-08
0.456371.6196672.012317e-08
0.4570111.6195641.981011e-08
0.4576521.6194611.949661e-08
0.4582941.6193591.918267e-08
0.4589381.6192571.886830e-08
0.4595821.6191551.855348e-08
0.461.6190891.834900e-08
0.4602271.6190531.827110e-08
0.4608731.6189521.804913e-08
0.4615191.6188511.782684e-08
0.4621671.6187511.760424e-08
0.4628161.6186511.738132e-08
0.4634651.6185511.715810e-08
0.4641161.6184521.693456e-08
0.4647671.6183531.671070e-08
0.465421.6182541.648653e-08
0.4660731.6181561.626205e-08
0.4667271.6180581.603725e-08
0.4673821.617961.581214e-08
0.4680381.6178631.558671e-08
0.4686951.6177661.536096e-08
0.4693531.6176691.513490e-08
0.4700121.6175731.490852e-08
0.4706711.6174771.468183e-08
0.4713321.6173811.445481e-08
0.4719931.6172861.422748e-08
0.4726561.6171911.399982e-08
0.4733191.6170961.377185e-08
0.4739841.6170021.354356e-08
0.4746491.6169081.331494e-08
0.4753151.6168141.308601e-08
0.4759821.6167211.285675e-08
0.476651.6166281.262718e-08
0.4773191.6165351.239728e-08
0.4779891.6164421.216706e-08
0.478661.616351.193651e-08
0.4793321.6162581.170564e-08
0.481.6161671.147600e-08
0.4800051.6161671.147431e-08
0.4806781.6160751.122184e-08
0.4813531.6159841.096901e-08
0.4820281.6158941.071583e-08
0.4827051.6158031.046229e-08
0.4833821.6157131.020840e-08
0.4840611.6156249.954147e-09
0.484741.6155349.699541e-09
0.4854211.6154459.444577e-09
0.4861021.6153569.189256e-09
0.4867841.6152688.933576e-09
0.4874671.615188.677537e-09
0.4881521.6150928.421139e-09
0.4888371.6150048.164382e-09
0.4895231.6149177.907263e-09
0.490211.6148297.649784e-09
0.4908981.6147437.391944e-09
0.4915871.6146567.133741e-09
0.4922771.614576.875176e-09
0.4929681.6144846.616249e-09
0.493661.6143986.356957e-09
0.4943531.6143136.097302e-09
0.4950461.6142285.837283e-09
0.4957411.6141435.576899e-09
0.4964371.6140595.316149e-09
0.4971341.6139745.055033e-09
0.4978321.613894.793550e-09
0.498531.6138074.531701e-09
0.499231.6137234.269484e-09
0.4999311.613644.006899e-09
0.51.6136323.980900e-09
0.5006321.6135573.985934e-09
0.5013351.6134753.991529e-09
0.5020391.6133923.997131e-09
0.5027431.613314.002741e-09
0.5034491.6132284.008360e-09
0.5041551.6131474.013986e-09
0.5048631.6130654.019619e-09
0.5055721.6129844.025261e-09
0.5062811.6129044.030911e-09
0.5069921.6128234.036569e-09
0.5077031.6127434.042234e-09
0.5084161.6126634.047908e-09
0.509131.6125834.053589e-09
0.5098441.6125044.059279e-09
0.510561.6124254.064976e-09
0.5112761.6123464.070682e-09
0.5119941.6122674.076395e-09
0.5127121.6121894.082117e-09
0.5134321.612114.087846e-09
0.5141531.6120324.093584e-09
0.5148741.6119554.099329e-09
0.5155971.6118774.105083e-09
0.5163211.61184.110845e-09
0.5170451.6117234.116614e-09
0.5177711.6116464.122392e-09
0.5184981.611574.128178e-09
0.5192251.6114944.133973e-09
0.5199541.6114184.139775e-09
0.5206841.6113424.145585e-09
0.5214151.6112664.151404e-09
0.5221471.6111914.157231e-09
0.5228791.6111164.163066e-09
0.5236131.6110414.168909e-09
0.5243481.6109674.174760e-09
0.5250841.6108924.180620e-09
0.5258211.6108184.186487e-09
0.5265591.6107454.192363e-09
0.5272981.6106714.198248e-09
0.5280381.6105984.204140e-09
0.5287791.6105244.210041e-09
0.5295211.6104514.215950e-09
0.5302651.6103794.221867e-09
0.5310091.6103064.227793e-09
0.5317541.6102344.233727e-09
0.5325011.6101624.239669e-09
0.5332481.610094.245620e-09
0.5339961.6100194.251579e-09
0.5347461.6099474.257546e-09
0.5354961.6098764.263522e-09
0.5362481.6098054.269506e-09
0.5370011.6097354.275499e-09
0.5377541.6096644.281500e-09
0.5385091.6095944.287509e-09
0.5392651.6095244.293527e-09
0.5400221.6094544.299553e-09
0.540781.6093844.305588e-09
0.5415391.6093154.311631e-09
0.5422991.6092464.317682e-09
0.543061.6091774.323743e-09
0.5438221.6091084.329811e-09
0.5445851.6090394.335888e-09
0.545351.6089714.341974e-09
0.5461151.6089034.348068e-09
0.5468821.6088354.354171e-09
0.5476491.6087674.360282e-09
0.5484181.60874.366402e-09
0.5491871.6086334.372531e-09
0.5499581.6085654.378668e-09
0.551.6085624.379000e-09
0.550731.6084994.454645e-09
0.5515031.6084324.534723e-09
0.5522771.6083654.614913e-09
0.5530521.6082994.695216e-09
0.5538291.6082334.775631e-09
0.5546061.6081674.856159e-09
0.5553841.6081024.936801e-09
0.5561641.6080365.017555e-09
0.5569441.6079715.098423e-09
0.5577261.6079065.179404e-09
0.5585091.6078415.260499e-09
0.5592931.6077765.341708e-09
0.5600781.6077125.423031e-09
0.5608641.6076475.504468e-09
0.5616511.6075835.586019e-09
0.5624391.6075195.667685e-09
0.5632291.6074565.749465e-09
0.5640191.6073925.831360e-09
0.5648111.6073295.913370e-09
0.5656041.6072655.995495e-09
0.5663971.6072026.077736e-09
0.5671921.607146.160091e-09
0.5679881.6070776.242563e-09
0.5687861.6070156.325150e-09
0.5695841.6069526.407853e-09
0.5703831.606896.490672e-09
0.5711841.6068296.573608e-09
0.5719861.6067676.656659e-09
0.5727881.6067056.739828e-09
0.5735921.6066446.823113e-09
0.5743971.6065836.906515e-09
0.5752041.6065226.990034e-09
0.5760111.6064617.073670e-09
0.5768191.6064017.157424e-09
0.5776291.606347.241295e-09
0.578441.606287.325284e-09
0.5792511.606227.409391e-09
0.5800641.606167.493615e-09
0.5808791.6061017.577958e-09
0.5816941.6060417.662420e-09
0.582511.6059827.747000e-09
0.5833281.6059227.831699e-09
0.5841471.6058637.916516e-09
0.5849661.6058058.001453e-09
0.5857871.6057468.086508e-09
0.586611.6056888.171684e-09
0.5874331.6056298.256978e-09
0.5882571.6055718.342393e-09
0.5890831.6055138.427927e-09
0.589911.6054558.513582e-09
0.5907381.6053988.599356e-09
0.5915671.605348.685251e-09
0.5923971.6052838.771267e-09
0.5932291.6052268.857403e-09
0.5940611.6051698.943660e-09
0.5948951.6051129.030038e-09
0.595731.6050559.116538e-09
0.5965661.6049999.203159e-09
0.5974031.6049439.289901e-09
0.5982421.6048879.376765e-09
0.5990821.6048319.463751e-09
0.5999221.6047759.550860e-09
0.61.604779.558900e-09
0.6007641.6047199.491881e-09
0.6016081.6046649.417953e-09
0.6024521.6046089.343922e-09
0.6032981.6045539.269787e-09
0.6041441.6044989.195547e-09
0.6049921.6044439.121204e-09
0.6058411.6043899.046756e-09
0.6066921.6043348.972204e-09
0.6075431.604288.897547e-09
0.6083961.6042258.822785e-09
0.609251.6041718.747918e-09
0.6101051.6041178.672946e-09
0.6109611.6040648.597869e-09
0.6118191.604018.522687e-09
0.6126771.6039578.447399e-09
0.6135371.6039038.372006e-09
0.6143981.603858.296506e-09
0.6152611.6037978.220901e-09
0.6161241.6037448.145189e-09
0.6169891.6036928.069372e-09
0.6178551.6036397.993448e-09
0.6187221.6035877.917417e-09
0.6195911.6035357.841279e-09
0.620461.6034827.765035e-09
0.6213311.6034317.688684e-09
0.6222031.6033797.612225e-09
0.6230761.6033277.535660e-09
0.6239511.6032767.458987e-09
0.6248271.6032247.382206e-09
0.6257041.6031737.305317e-09
0.6265821.6031227.228321e-09
0.6274611.6030717.151216e-09
0.6283421.603027.074003e-09
0.6292241.602976.996682e-09
0.6301071.6029196.919252e-09
0.6309911.6028696.841714e-09
0.6318771.6028196.764067e-09
0.6327641.6027696.686311e-09
0.6336521.6027196.608445e-09
0.6345411.6026696.530471e-09
0.6354321.6026196.452387e-09
0.6363241.602576.374193e-09
0.6372171.602526.295890e-09
0.6381111.6024716.217477e-09
0.6390071.6024226.138953e-09
0.6399041.6023736.060320e-09
0.6408021.6023245.981576e-09
0.6417011.6022765.902721e-09
0.6426021.6022275.823756e-09
0.6435041.6021795.744680e-09
0.6444071.6021315.665494e-09
0.6453111.6020825.586195e-09
0.6462171.6020345.506786e-09
0.6471241.6019875.427265e-09
0.6480321.6019395.347633e-09
0.6489421.6018915.267889e-09
0.6498521.6018445.188033e-09
0.651.6018365.175100e-09
0.6507651.6017975.181188e-09
0.6516781.6017495.188460e-09
0.6525931.6017025.195742e-09
0.6535091.6016555.203035e-09
0.6544261.6016095.210338e-09
0.6553441.6015625.217651e-09
0.6562641.6015165.224974e-09
0.6571851.6014695.232308e-09
0.6581081.6014235.239652e-09
0.6590311.6013775.247006e-09
0.6599561.6013315.254371e-09
0.6608821.6012855.261746e-09
0.661811.6012395.269131e-09
0.6627391.6011945.276527e-09
0.6636691.6011485.283933e-09
0.6646011.6011035.291349e-09
0.6655331.6010585.298776e-09
0.6664671.6010125.306213e-09
0.6674031.6009675.313661e-09
0.668341.6009235.321119e-09
0.6692781.6008785.328588e-09
0.6702171.6008335.336067e-09
0.6711581.6007895.343557e-09
0.67211.6007445.351057e-09
0.6730431.60075.358567e-09
0.6739881.6006565.366089e-09
0.6749331.6006125.373620e-09
0.6758811.6005685.381163e-09
0.6768291.6005245.388716e-09
0.6777791.6004815.396279e-09
0.6787311.6004375.403853e-09
0.6796831.6003945.411438e-09
0.6806371.6003515.419033e-09
0.6815921.6003085.426639e-09
0.6825491.6002655.434256e-09
0.6835071.6002225.441884e-09
0.6844661.6001795.449522e-09
0.6854271.6001365.457171e-09
0.6863891.6000945.464830e-09
0.6873521.6000515.472500e-09
0.6883171.6000095.480182e-09
0.6892831.5999675.487873e-09
0.6902511.5999255.495576e-09
0.6912191.5998835.503290e-09
0.692191.5998415.511014e-09
0.6931611.5997995.518749e-09
0.6941341.5997585.526495e-09
0.6951081.5997165.534252e-09
0.6960841.5996755.542020e-09
0.6970611.5996345.549798e-09
0.6980391.5995925.557588e-09
0.6990191.5995515.565389e-09
0.71.5995115.573200e-09

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
—