Optical constants

Refractive index of N-BK7HTi (SCHOTT)

N-BK7HTi: n,k 0.3–2.5 µm

Data
formula 2 + tabulated k
Range
0.3–2.5 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.3–2.5 µm
Refractive index n
1.5168
Extinction coefficient k
4.12045e-09
Permittivity ε1
2.30068
Permittivity ε2
1.24998e-08
Absorption coefficient α
0.000881196 cm⁻¹
Penetration depth δ = λ/(2πk)
2.26964e+10 nm
Abbe number Vd
64.167
Chromatic dispersion dn/dλ
-0.041792 µm⁻¹
Group index ng
1.54136
Group velocity dispersion
70.3722 fs²/mm
Dispersion parameter D
-383.918 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-BK7HTi (SCHOTT): N-BK7HTi
schott_n_bk7hti = ls.fetch_refractiveindex("specs", "SCHOTT-optical", "N-BK7HTi", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(schott_n_bk7hti.range_nm)  # (300, 2500) nm
eps = schott_n_bk7hti.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=1.03961212λ2λ2−0.00600069867+0.231792344λ2λ2−0.0200179144+1.01046945λ2λ2−103.560653

Valid from 0.3 to 2.5 µm.

Coefficients as stored
CiValue
C10.0
C21.03961212
C30.00600069867
C40.231792344
C50.0200179144
C61.01046945
C7103.560653

Comments and conditions

i-line glass

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: 1.86e-06 1.31e-08 -1.37e-11 4.34e-07 6.27e-10 0.17
nd
1.5168
Vd
64.17
glass code
517642.251
glass status
standard
density
value: 2510
thermal expansion
value: 7.1e-06, temperature range: 243 343; value: 8.3e-06, temperature range: 293 573
dPgF
-0.0009
resistance
acid: 1.0; stain: 0.0; alkali: 2.3; climatic: 1.0; phosphate: 2.3

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 1.29e-06 K⁻¹ at 633 nm, dn/dT = 8.88e-07 K⁻¹ at 1310 nm, dn/dT = 8.52e-07 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 423 wavelengths, the same grid as the API and the library
N-BK7HTi (SCHOTT), N-BK7HTi: n and k versus wavelength
λ (µm)nk
0.31.552773.602200e-06
0.3015981.5522073.250195e-06
0.3032051.5516522.896314e-06
0.3048211.5511042.540547e-06
0.3064451.5505642.182885e-06
0.3080781.5500311.823317e-06
0.3097191.5495061.461834e-06
0.311.5494171.400000e-06
0.3113691.5489871.279534e-06
0.3130281.5484761.133595e-06
0.3146961.5479719.868781e-07
0.3163731.5474748.393795e-07
0.3180591.5469836.910951e-07
0.3197531.5464985.420206e-07
0.321.5464295.203200e-07
0.3214571.546024.809439e-07
0.323171.5455494.346556e-07
0.3248921.5450833.881206e-07
0.3266231.5446243.413378e-07
0.3283631.5441712.943056e-07
0.3301121.5437242.470229e-07
0.3318711.5432821.994882e-07
0.333641.5428471.517002e-07
0.3341.5427591.419600e-07
0.3354171.5424171.330036e-07
0.3372041.5419921.217097e-07
0.3390011.5415731.103556e-07
0.3408071.541169.894104e-08
0.3426231.5407518.746566e-08
0.3444491.5403487.592913e-08
0.3462841.539956.433114e-08
0.3481291.5395585.267135e-08
0.3499841.539174.094943e-08
0.351.5391664.084700e-08
0.3518491.5387873.797709e-08
0.3537231.5384083.506658e-08
0.3556081.5380353.214057e-08
0.3575031.5376662.919897e-08
0.3594071.5373022.624170e-08
0.3613221.5369432.326867e-08
0.3632481.5365872.027980e-08
0.3651.536271.755900e-08
0.3651831.5362371.739320e-08
0.3671291.535891.562959e-08
0.3690851.5355481.385659e-08
0.371.535391.302700e-08
0.3710511.535211.267887e-08
0.3730281.5348771.202419e-08
0.3750161.5345471.136602e-08
0.3770141.5342211.070435e-08
0.3790231.5338991.003915e-08
0.381.5337459.715500e-09
0.3810421.5335829.481584e-09
0.3830721.5332689.025879e-09
0.3851131.5329578.567747e-09
0.3871651.5326518.107173e-09
0.3892281.5323487.644146e-09
0.391.5322367.470900e-09
0.3913021.5320497.162624e-09
0.3933871.5317536.668984e-09
0.3954831.5314616.172714e-09
0.397591.5311735.673800e-09
0.3997081.5308875.172228e-09
0.41.5308495.103200e-09
0.4018381.5306065.126655e-09
0.4039791.5303275.153974e-09
0.4051.5301965.167000e-09
0.4061321.5300525.181432e-09
0.4082961.529785.209029e-09
0.4104711.5295115.236773e-09
0.4126581.5292455.264665e-09
0.4148571.5289835.292705e-09
0.4170671.5287235.320895e-09
0.4192891.5284665.349235e-09
0.421.5283855.358300e-09
0.4215231.5282135.377740e-09
0.4237691.5279625.406404e-09
0.4260271.5277145.435220e-09
0.4282971.5274695.464189e-09
0.4305791.5272275.493314e-09
0.4328731.5269885.522593e-09
0.4351791.5267515.552028e-09
0.4361.5266685.562500e-09
0.4374981.5265175.581608e-09
0.4398291.5262865.611338e-09
0.4421731.5260575.641227e-09
0.4445291.5258315.671275e-09
0.4468971.5256075.701483e-09
0.4492781.5253865.731852e-09
0.4516721.5251675.762383e-09
0.4540781.5249515.793076e-09
0.4564981.5247375.823933e-09
0.458931.5245255.854955e-09
0.461.5244335.868600e-09
0.4613751.5243165.831232e-09
0.4638341.5241095.764441e-09
0.4663051.5239055.697295e-09
0.4687891.5237025.629790e-09
0.4712871.5235025.561927e-09
0.4737981.5233045.493701e-09
0.4763231.5231085.425112e-09
0.4788611.5229155.356158e-09
0.4814121.5227235.286836e-09
0.4839771.5225335.217145e-09
0.4865561.5223465.147082e-09
0.4891481.522165.076646e-09
0.4917541.5219775.005835e-09
0.4943741.5217954.934647e-09
0.4970081.5216154.863079e-09
0.4996571.5214374.791130e-09
0.51.5214144.781800e-09
0.5023191.5212614.716147e-09
0.5049951.5210874.640370e-09
0.5076861.5209154.564189e-09
0.5103911.5207444.487603e-09
0.513111.5205764.410608e-09
0.5158441.5204094.333203e-09
0.5185931.5202434.255386e-09
0.5213561.520084.177154e-09
0.5241341.5199184.098505e-09
0.5269261.5197584.019437e-09
0.5297341.5195993.939948e-09
0.5325561.5194423.860035e-09
0.5353941.5192863.779697e-09
0.5382461.5191323.698931e-09
0.5411141.518983.617734e-09
0.5439971.5188293.536104e-09
0.5461.5187263.479400e-09
0.5468961.518683.485109e-09
0.549811.5185323.503681e-09
0.5527391.5183863.522352e-09
0.5556841.5182413.541122e-09
0.5586451.5180973.559992e-09
0.5616211.5179553.578963e-09
0.5646141.5178143.598035e-09
0.5676221.5176743.617209e-09
0.5706461.5175363.636484e-09
0.5736871.51743.655863e-09
0.5767431.5172643.675344e-09
0.5798161.517133.694930e-09
0.581.5171223.696100e-09
0.5829061.5169973.858340e-09
0.5860111.5168654.031751e-09
0.5891341.5167354.206086e-09
0.5922731.5166054.381349e-09
0.5954281.5164774.557547e-09
0.5986011.516354.734683e-09
0.601791.5162244.912763e-09
0.6049971.51615.091792e-09
0.608221.5159765.271775e-09
0.6114611.5158545.452717e-09
0.6147191.5157335.634622e-09
0.6179941.5156125.817497e-09
0.621.5155395.929500e-09
0.6212871.5154935.941805e-09
0.6245971.5153755.973459e-09
0.6279251.5152586.005282e-09
0.6312711.5151426.037275e-09
0.6346341.5150276.069438e-09
0.6380151.5149126.101773e-09
0.6414151.5147996.134279e-09
0.6448321.5146876.166959e-09
0.6482681.5145766.199813e-09
0.6517221.5144656.232843e-09
0.6551951.5143566.266048e-09
0.6586851.5142476.299430e-09
0.661.5142076.312000e-09
0.6621951.514146.210415e-09
0.6657231.5140336.047128e-09
0.669271.5139275.882972e-09
0.6728361.5138225.717941e-09
0.6764211.5137185.552030e-09
0.6800251.5136145.385235e-09
0.6836481.5135115.217552e-09
0.6872911.513415.048975e-09
0.6909531.5133084.879501e-09
0.6946341.5132084.709123e-09
0.6983351.5131084.537837e-09
0.71.5130644.460800e-09
0.7020561.513014.454603e-09
0.7057971.5129114.443329e-09
0.7095571.5128144.431995e-09
0.7133381.5127174.420601e-09
0.7171391.5126214.409146e-09
0.720961.5125264.397630e-09
0.7248011.5124314.386053e-09
0.7286631.5123374.374414e-09
0.7325451.5122434.362712e-09
0.7364481.512154.350949e-09
0.7403721.5120584.339123e-09
0.7443171.5119674.327234e-09
0.7482831.5118764.315281e-09
0.752271.5117854.303265e-09
0.7562781.5116954.291185e-09
0.7603071.5116064.279041e-09
0.7643581.5115174.266831e-09
0.7684311.5114294.254557e-09
0.7725251.5113414.242218e-09
0.7766411.5112544.229812e-09
0.7807791.5111674.217341e-09
0.7849391.5110814.204803e-09
0.7891211.5109954.192198e-09
0.7933261.510914.179526e-09
0.7975531.5108254.166787e-09
0.8018021.5107414.153979e-09
0.8060741.5106574.141104e-09
0.8103691.5105734.128159e-09
0.8146871.510494.115146e-09
0.8190281.5104074.102064e-09
0.8233911.5103254.088912e-09
0.8277791.5102434.075690e-09
0.8321891.5101624.062397e-09
0.8366231.510084.049033e-09
0.8410811.514.035599e-09
0.8455621.5099194.022092e-09
0.8500671.5098394.008514e-09
0.8545961.5097593.994863e-09
0.859151.509683.981140e-09
0.8637271.50963.967344e-09
0.8683291.5095223.953474e-09
0.8729561.5094433.939530e-09
0.8776071.5093653.925512e-09
0.8822831.5092873.911419e-09
0.8869841.5092093.897251e-09
0.891711.5091313.883007e-09
0.8964611.5090543.868688e-09
0.9012381.5089773.854293e-09
0.9060391.50893.839820e-09
0.9108671.5088233.825271e-09
0.915721.5087473.810644e-09
0.9205991.5086713.795939e-09
0.9255041.5085953.781156e-09
0.9304351.5085193.766294e-09
0.9353931.5084433.751353e-09
0.9403771.5083683.736332e-09
0.9453871.5082923.721231e-09
0.9504241.5082173.706050e-09
0.9554881.5081423.690788e-09
0.9605791.5080673.675444e-09
0.9656971.5079923.660019e-09
0.9708421.5079173.644511e-09
0.9760151.5078433.628921e-09
0.9812151.5077683.613248e-09
0.9864431.5076933.597492e-09
0.9916991.5076193.581651e-09
0.9969831.5075443.565726e-09
1.00231.507473.549716e-09
1.007641.5073963.533621e-09
1.0131.5073223.517440e-09
1.01841.5072473.501173e-09
1.023831.5071733.484819e-09
1.029281.5070993.468379e-09
1.034771.5070253.451850e-09
1.040281.506953.435234e-09
1.045821.5068763.418528e-09
1.05141.5068023.401734e-09
1.0571.5067273.384851e-09
1.061.5066883.375800e-09
1.062631.5066533.713350e-09
1.068291.5065784.440361e-09
1.073981.5065045.171246e-09
1.07971.5064295.906025e-09
1.085461.5063556.644718e-09
1.091241.506287.387348e-09
1.097061.5062058.133934e-09
1.10291.506138.884499e-09
1.108781.5060559.639062e-09
1.114681.5059791.039765e-08
1.120621.5059041.116027e-08
1.126591.5058291.192696e-08
1.13261.5057531.269773e-08
1.138631.5056771.347261e-08
1.14471.5056011.425162e-08
1.15081.5055251.503478e-08
1.156931.5054481.582212e-08
1.163091.5053721.661364e-08
1.169291.5052951.740939e-08
1.175521.5052181.820937e-08
1.181781.505141.901362e-08
1.188081.5050631.982215e-08
1.194411.5049852.063499e-08
1.200771.5049072.145216e-08
1.207171.5048292.227369e-08
1.21361.504752.309959e-08
1.220071.5046712.392989e-08
1.226571.5045922.476462e-08
1.233111.5045132.560379e-08
1.239681.5044332.644744e-08
1.246281.5043532.729558e-08
1.252921.5042722.814824e-08
1.25961.5041912.900544e-08
1.266311.504112.986721e-08
1.273061.5040293.073357e-08
1.279841.5039473.160455e-08
1.286661.5038643.248017e-08
1.293511.5037823.336045e-08
1.30041.5036993.424542e-08
1.307331.5036153.513511e-08
1.31431.5035313.602954e-08
1.32131.5034473.692873e-08
1.328341.5033623.783272e-08
1.335421.5032773.874152e-08
1.342531.5031913.965517e-08
1.349691.5031044.057368e-08
1.356881.5030184.149708e-08
1.364111.502934.242541e-08
1.371381.5028434.335868e-08
1.378681.5027544.429693e-08
1.386031.5026664.524017e-08
1.393411.5025764.618844e-08
1.400841.5024864.714176e-08
1.40831.5023964.810016e-08
1.415811.5023054.906367e-08
1.423351.5022135.003231e-08
1.430931.5021215.100612e-08
1.438561.5020285.198511e-08
1.446221.5019345.296931e-08
1.453931.501845.395877e-08
1.461671.5017455.495349e-08
1.469461.501655.595351e-08
1.477291.5015545.695886e-08
1.485161.5014575.796957e-08
1.493081.501365.898566e-08
1.501031.5012616.000717e-08
1.509031.5011626.103412e-08
1.517071.5010636.206654e-08
1.525151.5009626.310446e-08
1.531.5009026.372700e-08
1.533281.5008616.880140e-08
1.541451.5007598.144794e-08
1.549661.5006569.416185e-08
1.557921.5005531.069435e-07
1.566221.5004481.197933e-07
1.574561.5003431.327115e-07
1.582951.5002371.456985e-07
1.591391.500131.587548e-07
1.599871.5000221.718806e-07
1.608391.4999141.850764e-07
1.616961.4998041.983424e-07
1.625571.4996942.116792e-07
1.634241.4995822.250869e-07
1.642941.499472.385662e-07
1.65171.4993572.521172e-07
1.66051.4992422.657405e-07
1.669341.4991272.794363e-07
1.678241.4990112.932052e-07
1.687181.4988943.070473e-07
1.696171.4987753.209633e-07
1.705211.4986563.349533e-07
1.714291.4985363.490180e-07
1.723431.4984143.631575e-07
1.732611.4982923.773724e-07
1.741841.4981683.916630e-07
1.751121.4980434.060298e-07
1.760451.4979174.204731e-07
1.769831.497794.349934e-07
1.779261.4976624.495910e-07
1.788741.4975324.642664e-07
1.798271.4974014.790200e-07
1.807851.4972694.938522e-07
1.817491.4971365.087635e-07
1.827171.4970025.237542e-07
1.83691.4968665.388247e-07
1.846691.4967295.539756e-07
1.856531.4965915.692072e-07
1.866421.4964515.845199e-07
1.876371.496315.999143e-07
1.886371.4961676.153906e-07
1.896421.4960236.309494e-07
1.906521.4958786.465911e-07
1.916681.4957316.623162e-07
1.926891.4955836.781250e-07
1.937161.4954336.940181e-07
1.947481.4952827.099958e-07
1.957851.4951297.260587e-07
1.968291.4949757.422071e-07
1.971.494957.448600e-07
1.978771.4948198.032826e-07
1.989321.4946628.734888e-07
1.999921.4945039.440691e-07
2.010571.4943421.015025e-06
2.021281.494181.086360e-06
2.032051.4940161.158074e-06
2.042881.493851.230171e-06
2.053771.4936831.302652e-06
2.064711.4935131.375519e-06
2.075711.4933421.448774e-06
2.086771.493171.522419e-06
2.097891.4929951.596457e-06
2.109061.4928181.670889e-06
2.12031.492641.745718e-06
2.13161.492461.820946e-06
2.142961.4922781.896574e-06
2.154371.4920931.972606e-06
2.165851.4919072.049042e-06
2.177391.4917192.125886e-06
2.188991.4915292.203139e-06
2.200661.4913372.280804e-06
2.212381.4911422.358882e-06
2.224171.4909462.437377e-06
2.236021.4907472.516290e-06
2.247931.4905462.595623e-06
2.259911.4903432.675379e-06
2.271951.4901382.755560e-06
2.284061.489932.836168e-06
2.296231.489722.917205e-06
2.308461.4895082.998675e-06
2.320761.4892933.080578e-06
2.3251.4892193.108800e-06
2.333131.4890763.228055e-06
2.345561.4888563.410465e-06
2.358061.4886343.593847e-06
2.370621.488413.778207e-06
2.383251.4881833.963549e-06
2.395951.4879534.149878e-06
2.408711.4877214.337200e-06
2.421551.4874864.525520e-06
2.434451.4872484.714844e-06
2.447421.4870084.905176e-06
2.460461.4867645.096522e-06
2.473571.4865185.288888e-06
2.486751.4862695.482279e-06
2.51.4860185.676700e-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
—