Optical constants

Refractive index of N-BALF4 (SCHOTT)

N-BALF4: n,k 0.35–2.5 µm

Data
formula 2 + tabulated k
Range
0.35–2.5 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.35–2.5 µm
Refractive index n
1.57956
Extinction coefficient k
7.87323e-09
Permittivity ε1
2.495
Permittivity ε2
2.48724e-08
Absorption coefficient α
0.00168376 cm⁻¹
Penetration depth δ = λ/(2πk)
1.18782e+10 nm
Abbe number Vd
53.866
Chromatic dispersion dn/dλ
-0.055354 µm⁻¹
Group index ng
1.61208
Group velocity dispersion
99.335 fs²/mm
Dispersion parameter D
-541.925 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

# N-BALF4 (SCHOTT): N-BALF4
schott_n_balf4 = ls.fetch_refractiveindex("specs", "SCHOTT-optical", "N-BALF4", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(schott_n_balf4.range_nm)  # (350, 2500) nm
eps = schott_n_balf4.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=1.31004128λ2λ2−0.0079659645+0.142038259λ2λ2−0.0330672072+0.964929351λ2λ2−109.19732

Valid from 0.35 to 2.5 µm.

Coefficients as stored
CiValue
C10.0
C21.31004128
C30.0079659645
C40.142038259
C50.0330672072
C60.964929351
C7109.19732

Comments and conditions

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: 5.33e-06 1.47e-08 -1.58e-11 5.75e-07 6.58e-10 0.195
nd
1.57956
Vd
53.87
glass code
580539.311
glass status
standard
density
value: 3111
thermal expansion
value: 6.52e-06, temperature range: 243 343; value: 7.41e-06, temperature range: 293 573
dPgF
-0.0012
resistance
acid: 1.0; stain: 0.0; alkali: 1.0; climatic: 1.0; phosphate: 1.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 3.26e-06 K⁻¹ at 633 nm, dn/dT = 2.62e-06 K⁻¹ at 1310 nm, dn/dT = 2.56e-06 K⁻¹ at 1550 nm

References

Cite

SCHOTT Zemax catalog 2017-01-20b (obtained from http://www.schott.com); See also SCHOTT 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 419 wavelengths, the same grid as the API and the library
N-BALF4 (SCHOTT), N-BALF4: n and k versus wavelength
λ (µm)nk
0.351.6107851.078000e-06
0.3517291.6102679.922734e-07
0.3534661.6097569.061233e-07
0.3552121.6092518.195477e-07
0.3569671.6087537.325444e-07
0.358731.6082626.451113e-07
0.3605021.6077765.572464e-07
0.3622831.6072974.689474e-07
0.3640731.6068243.802122e-07
0.3651.6065833.342400e-07
0.3658711.6063583.167239e-07
0.3676791.6058972.803896e-07
0.3694951.6054422.438758e-07
0.371.6053172.337200e-07
0.371321.6049922.196905e-07
0.3731541.6045492.001962e-07
0.3749981.6041111.806057e-07
0.376851.6036781.609184e-07
0.3787121.6032511.411339e-07
0.381.6029591.274400e-07
0.3805821.6028291.244921e-07
0.3824621.6024121.149743e-07
0.3843521.6021.054095e-07
0.386251.6015949.579744e-08
0.3881581.6011928.613789e-08
0.391.6008117.681300e-08
0.3900761.6007957.658543e-08
0.3920021.6004037.077955e-08
0.3939391.6000166.494498e-08
0.3958851.5996335.908160e-08
0.397841.5992555.318925e-08
0.3998061.5988824.726780e-08
0.41.5988454.668200e-08
0.4017811.5985134.404148e-08
0.4037651.5981484.109817e-08
0.4051.5979253.926700e-08
0.405761.5977883.857711e-08
0.4077641.5974323.675702e-08
0.4097781.597083.492794e-08
0.4118031.5967333.308983e-08
0.4138371.5963893.124263e-08
0.4158811.596052.938631e-08
0.4179351.5957142.752082e-08
0.421.5953822.564612e-08
0.421.5953822.564600e-08
0.4220751.5950542.540613e-08
0.424161.594732.516506e-08
0.4262551.594412.492279e-08
0.428361.5940932.467933e-08
0.4304761.593782.443467e-08
0.4326031.593472.418880e-08
0.434741.5931652.394171e-08
0.4361.5929862.379600e-08
0.4368871.5928622.367947e-08
0.4390451.5925632.339604e-08
0.4412141.5922672.311121e-08
0.4433941.5919752.282497e-08
0.4455841.5916862.253731e-08
0.4477851.59142.224824e-08
0.4499971.5911172.195773e-08
0.452221.5908382.166580e-08
0.4544541.5905612.137242e-08
0.4566991.5902882.107759e-08
0.4589551.5900172.078130e-08
0.461.5898942.064400e-08
0.4612221.589752.035495e-08
0.46351.5894861.981590e-08
0.465791.5892241.927418e-08
0.468091.5889651.872979e-08
0.4704031.5887091.818271e-08
0.4727261.5884561.763293e-08
0.4750621.5882061.708043e-08
0.4774081.5879581.652520e-08
0.4797671.5877131.596723e-08
0.4821361.5874711.540651e-08
0.4845181.5872311.484301e-08
0.4869121.5869941.427673e-08
0.4893171.5867591.370766e-08
0.4917341.5865271.313577e-08
0.4941631.5862971.256106e-08
0.4966041.586071.198350e-08
0.4990571.5858451.140310e-08
0.51.5857591.118000e-08
0.5015221.5856221.109832e-08
0.5041.5854021.096538e-08
0.5064891.5851841.083179e-08
0.5089911.5849691.069754e-08
0.5115061.5847551.056263e-08
0.5140321.5845441.042705e-08
0.5165711.5843351.029080e-08
0.5191231.5841281.015387e-08
0.5216881.5839241.001627e-08
0.5242651.5837219.877995e-09
0.5268541.583529.739033e-09
0.5294571.5833229.599384e-09
0.5320721.5831259.459046e-09
0.5347011.5829319.318014e-09
0.5373421.5827389.176286e-09
0.5399961.5825489.033857e-09
0.5426641.5823598.890725e-09
0.5453441.5821728.746886e-09
0.5461.5821278.711700e-09
0.5480381.5819878.633046e-09
0.5507451.5818048.528573e-09
0.5534661.5816238.423584e-09
0.55621.5814438.318076e-09
0.5589471.5812668.212047e-09
0.5617081.581098.105494e-09
0.5644831.5809157.998415e-09
0.5672721.5807437.890807e-09
0.5700741.5805727.782667e-09
0.572891.5804037.673993e-09
0.575721.5802357.564783e-09
0.5785641.5800697.455033e-09
0.581.5799867.399600e-09
0.5814221.5799057.488192e-09
0.5842941.5797427.667180e-09
0.587181.5795817.847052e-09
0.590081.5794218.027813e-09
0.5929951.5792638.209467e-09
0.5959251.5791068.392018e-09
0.5988681.5789518.575471e-09
0.6018271.5787978.759831e-09
0.6047991.5786448.945100e-09
0.6077871.5784939.131285e-09
0.6107891.5783449.318390e-09
0.6138061.5781969.506419e-09
0.6168391.5780499.695377e-09
0.6198861.5779039.885268e-09
0.621.5778989.892400e-09
0.6229481.5777599.939459e-09
0.6260251.5776169.988587e-09
0.6291171.5774751.003796e-08
0.6322251.5773351.008757e-08
0.6353481.5771951.013743e-08
0.6384861.5770581.018754e-08
0.641641.5769211.023789e-08
0.644811.5767861.028849e-08
0.6479951.5766521.033934e-08
0.6511961.5765191.039045e-08
0.6544131.5763871.044180e-08
0.6576461.5762561.049341e-08
0.661.5761621.053100e-08
0.6608941.5761261.044524e-08
0.6641591.5759981.013213e-08
0.667441.5758719.817468e-09
0.6707371.5757449.501253e-09
0.674051.5756199.183476e-09
0.677381.5754958.864130e-09
0.6807261.5753728.543206e-09
0.6840881.575258.220697e-09
0.6874671.5751297.896595e-09
0.6908631.5750097.570892e-09
0.6942761.5748897.243580e-09
0.6977061.5747716.914651e-09
0.71.5746936.694600e-09
0.7011521.5746546.749031e-09
0.7046161.5745386.912657e-09
0.7080961.5744237.077092e-09
0.7115941.5743087.242339e-09
0.7151091.5741957.408403e-09
0.7186421.5740827.575286e-09
0.7221921.573977.742994e-09
0.7257591.5738597.911531e-09
0.7293441.5737498.080900e-09
0.7329471.573648.251105e-09
0.7365681.5735328.422152e-09
0.7402061.5734248.594043e-09
0.7438621.5733188.766784e-09
0.7475371.5732128.940377e-09
0.751231.5731069.114829e-09
0.754941.5730029.290142e-09
0.758671.5728989.466321e-09
0.7624171.5727959.643370e-09
0.7661841.5726939.821294e-09
0.7699681.5725921.000010e-08
0.7737721.5724911.017978e-08
0.7775941.5723911.036036e-08
0.7814351.5722921.054182e-08
0.7852951.5721931.072418e-08
0.7891741.5720951.090745e-08
0.7930731.5719981.109161e-08
0.796991.5719011.127669e-08
0.8009271.5718051.146268e-08
0.8048841.5717091.164960e-08
0.808861.5716141.183743e-08
0.8128551.571521.202619e-08
0.816871.5714261.221589e-08
0.8209061.5713331.240652e-08
0.8249611.5712411.259809e-08
0.8290361.5711491.279061e-08
0.8331311.5710571.298408e-08
0.8372471.5709671.317851e-08
0.8413821.5708761.337389e-08
0.8455391.5707861.357025e-08
0.8497151.5706971.376757e-08
0.8539131.5706081.396586e-08
0.8581311.570521.416514e-08
0.862371.5704321.436540e-08
0.866631.5703451.456665e-08
0.8709111.5702581.476889e-08
0.8752131.5701711.497214e-08
0.8795361.5700851.517638e-08
0.8838811.571.538164e-08
0.8882471.5699151.558791e-08
0.8926351.569831.579520e-08
0.8970441.5697461.600351e-08
0.9014751.5696621.621285e-08
0.9059281.5695781.642323e-08
0.9104031.5694951.663464e-08
0.9149011.5694121.684710e-08
0.919421.569331.706061e-08
0.9239621.5692481.727517e-08
0.9285261.5691661.749079e-08
0.9331131.5690851.770748e-08
0.9377221.5690041.792524e-08
0.9423541.5689231.814408e-08
0.9470091.5688431.836399e-08
0.9516871.5687631.858499e-08
0.9563881.5686831.880709e-08
0.9611121.5686031.903028e-08
0.965861.5685241.925457e-08
0.9706311.5684451.947997e-08
0.9754261.5683661.970648e-08
0.9802441.5682881.993412e-08
0.9850861.568212.016288e-08
0.9899531.5681322.039276e-08
0.9948431.5680542.062379e-08
0.9997571.5679762.085595e-08
1.00471.5678992.108926e-08
1.009661.5678222.132373e-08
1.014651.5677452.155935e-08
1.019661.5676682.179613e-08
1.024691.5675922.203409e-08
1.029761.5675162.227322e-08
1.034841.5674392.251353e-08
1.039961.5673632.275503e-08
1.045091.5672872.299772e-08
1.050251.5672122.324162e-08
1.055441.5671362.348671e-08
1.061.567072.370200e-08
1.060661.5670612.377862e-08
1.06591.5669852.439007e-08
1.071161.566912.500454e-08
1.076451.5668352.562204e-08
1.081771.566762.624260e-08
1.087111.5666852.686622e-08
1.092481.566612.749292e-08
1.097881.5665352.812271e-08
1.10331.566462.875562e-08
1.108751.5663852.939165e-08
1.114231.5663113.003083e-08
1.119731.5662363.067316e-08
1.125271.5661613.131867e-08
1.130821.5660873.196736e-08
1.136411.5660123.261926e-08
1.142021.5659383.327438e-08
1.147671.5658633.393273e-08
1.153331.5657893.459434e-08
1.159031.5657143.525922e-08
1.164761.5656393.592737e-08
1.170511.5655653.659883e-08
1.176291.565493.727361e-08
1.18211.5654153.795172e-08
1.187941.5653413.863318e-08
1.193811.5652663.931801e-08
1.199711.5651914.000622e-08
1.205631.5651164.069782e-08
1.211591.5650414.139285e-08
1.217571.5649654.209131e-08
1.223591.564894.279322e-08
1.229631.5648154.349859e-08
1.235711.5647394.420745e-08
1.241811.5646644.491981e-08
1.247951.5645884.563569e-08
1.254111.5645124.635511e-08
1.260311.5644364.707808e-08
1.266531.564364.780462e-08
1.272791.5642834.853475e-08
1.279071.5642074.926849e-08
1.285391.564135.000585e-08
1.291741.5640535.074686e-08
1.298121.5639765.149152e-08
1.304541.5638995.223987e-08
1.310981.5638215.299191e-08
1.317461.5637435.374766e-08
1.323961.5636655.450715e-08
1.33051.5635875.527039e-08
1.337081.5635095.603740e-08
1.343681.563435.680820e-08
1.350321.5633515.758280e-08
1.356991.5632715.836123e-08
1.363691.5631925.914351e-08
1.370431.5631125.992965e-08
1.37721.5630326.071968e-08
1.3841.5629516.151361e-08
1.390841.5628716.231146e-08
1.397711.562796.311325e-08
1.404611.5627086.391900e-08
1.411551.5626266.472873e-08
1.418521.5625446.554246e-08
1.425531.5624626.636022e-08
1.432571.5623796.718201e-08
1.439651.5622966.800786e-08
1.446761.5622126.883779e-08
1.453911.5621286.967182e-08
1.461091.5620447.050997e-08
1.468311.5619597.135226e-08
1.475561.5618747.219871e-08
1.482851.5617887.304934e-08
1.490171.5617027.390417e-08
1.497531.5616157.476323e-08
1.504931.5615287.562653e-08
1.512371.5614417.649409e-08
1.519841.5613537.736594e-08
1.527341.5612657.824210e-08
1.531.5612337.855200e-08
1.534891.5611768.348910e-08
1.542471.5610869.114533e-08
1.550091.5609969.883937e-08
1.557751.5609061.065714e-07
1.565441.5608151.143417e-07
1.573181.5607231.221503e-07
1.580951.5606311.299975e-07
1.588761.5605381.378834e-07
1.59661.5604451.458084e-07
1.604491.5603511.537724e-07
1.612421.5602571.617758e-07
1.620381.5601621.698188e-07
1.628391.5600661.779014e-07
1.636431.559971.860240e-07
1.644511.5598731.941868e-07
1.652641.5597752.023898e-07
1.66081.5596772.106334e-07
1.6691.5595782.189176e-07
1.677251.5594782.272429e-07
1.685531.5593782.356092e-07
1.693861.5592772.440168e-07
1.702231.5591752.524660e-07
1.710641.5590732.609570e-07
1.719091.558972.694898e-07
1.727581.5588662.780648e-07
1.736111.5587612.866822e-07
1.744691.5586562.953422e-07
1.753311.5585493.040449e-07
1.761971.5584423.127906e-07
1.770671.5583353.215795e-07
1.779421.5582263.304119e-07
1.788211.5581163.392878e-07
1.797041.5580063.482076e-07
1.805921.5578953.571715e-07
1.814841.5577833.661796e-07
1.82381.557673.752323e-07
1.832811.5575563.843297e-07
1.841871.5574413.934720e-07
1.850961.5573254.026594e-07
1.860111.5572084.118923e-07
1.86931.5570914.211707e-07
1.878531.5569724.304950e-07
1.887811.5568534.398654e-07
1.897141.5567324.492820e-07
1.906511.556614.587451e-07
1.915921.5564884.682550e-07
1.925391.5563644.778119e-07
1.93491.556244.874160e-07
1.944461.5561144.970675e-07
1.954061.5559875.067667e-07
1.963721.5558595.165138e-07
1.971.5557755.228600e-07
1.973421.555735.392700e-07
1.983161.55565.861036e-07
1.992961.5554686.331686e-07
2.00281.5553366.804661e-07
2.01271.5552027.279973e-07
2.022641.5550677.757632e-07
2.032631.5549318.237651e-07
2.042671.5547948.720041e-07
2.052761.5546569.204814e-07
2.06291.5545169.691981e-07
2.073091.5543751.018156e-06
2.083331.5542321.067355e-06
2.093631.5540891.116797e-06
2.103971.5539441.166484e-06
2.114361.5537971.216416e-06
2.12481.553651.266594e-06
2.13531.5535011.317021e-06
2.145851.553351.367696e-06
2.156451.5531981.418622e-06
2.16711.5530451.469800e-06
2.177811.552891.521230e-06
2.188561.5527341.572914e-06
2.199371.5525761.624854e-06
2.210241.5524171.677050e-06
2.221161.5522561.729504e-06
2.232131.5520931.782217e-06
2.243161.551931.835191e-06
2.254241.5517641.888426e-06
2.265371.5515971.941924e-06
2.276561.5514281.995686e-06
2.287811.5512572.049714e-06
2.299111.5510852.104009e-06
2.310471.5509112.158572e-06
2.321881.5507362.213405e-06
2.3251.5506882.228400e-06
2.333351.5505582.328886e-06
2.344871.5503792.467622e-06
2.356461.5501982.607043e-06
2.36811.5500162.747153e-06
2.37981.5498312.887955e-06
2.391551.5496453.029452e-06
2.403371.5494563.171648e-06
2.415241.5492663.314547e-06
2.427171.5490743.458152e-06
2.439161.5488793.602466e-06
2.451211.5486833.747493e-06
2.463311.5484853.893236e-06
2.475481.5482854.039699e-06
2.487711.5480824.186886e-06
2.51.5478784.334800e-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
—