Optical constants

Refractive index of N-LAK34 (SCHOTT)

N-LAK34: n,k 0.29–2.5 µm

Data
formula 2 + tabulated k
Range
0.29–2.5 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.29–2.5 µm
Refractive index n
1.72916
Extinction coefficient k
8.99870e-09
Permittivity ε1
2.98999
Permittivity ε2
3.11203e-08
Absorption coefficient α
0.00192446 cm⁻¹
Penetration depth δ = λ/(2πk)
1.03925e+10 nm
Abbe number Vd
54.499
Chromatic dispersion dn/dλ
-0.0690882 µm⁻¹
Group index ng
1.76975
Group velocity dispersion
120.92 fs²/mm
Dispersion parameter D
-659.685 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-LAK34 (SCHOTT): N-LAK34
schott_n_lak34 = ls.fetch_refractiveindex("specs", "SCHOTT-optical", "N-LAK34", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(schott_n_lak34.range_nm)  # (290, 2500) nm
eps = schott_n_lak34.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=1.26661442λ2λ2−0.00589278062+0.665919318λ2λ2−0.0197509041+1.1249612λ2λ2−78.8894174

Valid from 0.29 to 2.5 µm.

Coefficients as stored
CiValue
C10.0
C21.26661442
C30.00589278062
C40.665919318
C50.0197509041
C61.1249612
C778.8894174

Comments and conditions

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: 1.96e-06 9.65e-09 4.4e-12 4.91e-07 5.28e-10 0.161
nd
1.72916
Vd
54.5
glass code
729545.402
glass status
standard
density
value: 4019
thermal expansion
value: 5.81e-06, temperature range: 243 343; value: 6.91e-06, temperature range: 293 573
dPgF
-0.0079
resistance
acid: 52.3; stain: 0.0; alkali: 1.0; climatic: 1.0; phosphate: 3.3

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 1.88e-06 K⁻¹ at 633 nm, dn/dT = 1.26e-06 K⁻¹ at 1310 nm, dn/dT = 1.21e-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 424 wavelengths, the same grid as the API and the library
N-LAK34 (SCHOTT), N-LAK34: n and k versus wavelength
λ (µm)nk
0.291.7975444.251000e-06
0.291571.7964384.109315e-06
0.2931481.7953493.966863e-06
0.2947351.7942773.823640e-06
0.2963311.793223.679641e-06
0.2979351.792183.534863e-06
0.2995481.7911543.389301e-06
0.31.7908713.348500e-06
0.301171.7901443.263780e-06
0.30281.7891493.145675e-06
0.3044391.7881693.026931e-06
0.3060871.7872032.907543e-06
0.3077441.7862512.787510e-06
0.309411.7853132.666826e-06
0.311.7849852.624100e-06
0.3110851.7843882.517243e-06
0.3127691.7834772.351413e-06
0.3144621.7825782.184686e-06
0.3161651.7816932.017056e-06
0.3178761.780821.848518e-06
0.3195971.779961.679068e-06
0.321.7797611.639400e-06
0.3213271.7791121.569041e-06
0.3230671.7782751.476831e-06
0.3248161.7774511.384122e-06
0.3265741.7766381.290910e-06
0.3283421.7758361.197195e-06
0.330121.7750451.102972e-06
0.3319071.7742651.008238e-06
0.3337031.7734979.129924e-07
0.3341.7733718.972700e-07
0.335511.7727388.547000e-07
0.3373261.771998.034921e-07
0.3391521.7712527.520069e-07
0.3409881.7705257.002431e-07
0.3428341.7698076.481990e-07
0.344691.7690985.958732e-07
0.3465561.76845.432641e-07
0.3484321.767714.903702e-07
0.351.7671444.461700e-07
0.3503191.767034.415919e-07
0.3522151.7663594.143336e-07
0.3541221.7656973.869277e-07
0.3560391.7650443.593734e-07
0.3579661.7643993.316700e-07
0.3599041.7637633.038165e-07
0.3618521.7631352.758123e-07
0.3638111.7625162.476565e-07
0.3651.7621452.305700e-07
0.3657811.7619042.223036e-07
0.3677611.7613012.013377e-07
0.3697521.7607051.802583e-07
0.371.7606311.776300e-07
0.3717531.7601171.664870e-07
0.3737661.7595361.536976e-07
0.3757891.7589631.408390e-07
0.3778241.7583981.279108e-07
0.3798691.7578391.149126e-07
0.381.7578041.140800e-07
0.3819251.7572881.069046e-07
0.3839931.7567449.919940e-08
0.3860721.7562079.145252e-08
0.3881621.7556768.366371e-08
0.391.7552177.681300e-08
0.3902631.7551527.643996e-08
0.3923761.7546357.344374e-08
0.39451.7541247.043129e-08
0.3966351.753626.740255e-08
0.3987831.7531226.435740e-08
0.41.7528436.263100e-08
0.4009411.752636.099995e-08
0.4031121.7521445.723978e-08
0.4051.7517295.396900e-08
0.4052941.7516655.365510e-08
0.4074881.7511915.131447e-08
0.4096941.7507234.896117e-08
0.4119121.750264.659513e-08
0.4141421.7498044.421628e-08
0.4163841.7493534.182456e-08
0.4186381.7489073.941988e-08
0.421.7486423.796700e-08
0.4209041.7484673.748586e-08
0.4231831.7480333.627366e-08
0.4254741.7476033.505490e-08
0.4277771.7471793.382954e-08
0.4300931.746763.259755e-08
0.4324211.7463453.135889e-08
0.4347621.7459363.011352e-08
0.4361.7457232.945500e-08
0.4371161.7455322.897638e-08
0.4394821.7451322.796132e-08
0.4418611.7447372.694077e-08
0.4442531.7443472.591469e-08
0.4466581.7439622.488306e-08
0.4490761.7435812.384585e-08
0.4515071.7432042.280301e-08
0.4539521.7428322.175454e-08
0.4564091.7424642.070038e-08
0.458881.7421011.964052e-08
0.461.7419381.916000e-08
0.4613641.7417421.883327e-08
0.4638621.7413871.823498e-08
0.4663731.7410361.763345e-08
0.4688971.7406891.702866e-08
0.4714361.7403461.642060e-08
0.4739881.7400071.580924e-08
0.4765541.7396721.519458e-08
0.4791341.739341.457658e-08
0.4817271.7390131.395525e-08
0.4843351.7386891.333055e-08
0.4869571.7383691.270246e-08
0.4895931.7380521.207098e-08
0.4922441.7377391.143608e-08
0.4949091.737431.079774e-08
0.4975881.7371241.015595e-08
0.51.7368529.578100e-09
0.5002811.7368219.551446e-09
0.502991.7365229.294967e-09
0.5057131.7362269.037098e-09
0.508451.7359338.777834e-09
0.5112031.7356448.517166e-09
0.513971.7353578.255087e-09
0.5167531.7350747.991589e-09
0.519551.7347947.726665e-09
0.5223631.7345177.460307e-09
0.525191.7342437.192506e-09
0.5280341.7339726.923256e-09
0.5308921.7337046.652549e-09
0.5337661.7334396.380376e-09
0.5366561.7331766.106729e-09
0.5395611.7329175.831601e-09
0.5424821.732665.554984e-09
0.5454191.7324065.276869e-09
0.5461.7323565.221800e-09
0.5483711.7321545.503009e-09
0.551341.7319065.855078e-09
0.5543241.7316596.209052e-09
0.5573251.7314166.564943e-09
0.5603421.7311756.922761e-09
0.5633761.7309367.282516e-09
0.5664261.73077.644218e-09
0.5694921.7304668.007878e-09
0.5725751.7302358.373507e-09
0.5756751.7300068.741115e-09
0.5787911.7297799.110713e-09
0.581.7296929.254100e-09
0.5819241.7295559.189435e-09
0.5850751.7293339.083571e-09
0.5882421.7291138.977133e-09
0.5914261.7288968.870120e-09
0.5946281.728688.762527e-09
0.5978471.7284678.654352e-09
0.6010831.7282558.545591e-09
0.6043371.7280468.436241e-09
0.6076091.7278398.326299e-09
0.6108981.7276348.215763e-09
0.6142051.7274318.104627e-09
0.617531.727237.992890e-09
0.621.7270827.909900e-09
0.6208731.7270317.875009e-09
0.6242351.7268337.740741e-09
0.6276141.7266387.605747e-09
0.6310111.7264447.470021e-09
0.6344271.7262527.333561e-09
0.6378621.7260627.196362e-09
0.6413151.7258747.058421e-09
0.6447871.7256886.919732e-09
0.6482771.7255036.780293e-09
0.6517871.725326.640099e-09
0.6553151.7251386.499146e-09
0.6588631.7249596.357430e-09
0.661.7249026.312000e-09
0.662431.724786.335238e-09
0.6660161.7246046.369539e-09
0.6696211.7244296.404025e-09
0.6732461.7242556.438699e-09
0.6768911.7240836.473559e-09
0.6805551.7239136.508609e-09
0.6842391.7237446.543848e-09
0.6879431.7235766.579278e-09
0.6916681.723416.614900e-09
0.6954121.7232456.650715e-09
0.6991771.7230826.686723e-09
0.71.7230476.694600e-09
0.7029621.722926.778661e-09
0.7067671.7227596.886678e-09
0.7105931.72266.995279e-09
0.714441.7224427.104469e-09
0.7183081.7222857.214249e-09
0.7221961.722137.324624e-09
0.7261061.7219757.435596e-09
0.7300361.7218227.547169e-09
0.7339891.721677.659346e-09
0.7379621.721527.772131e-09
0.7419571.721377.885526e-09
0.7459741.7212217.999534e-09
0.7500121.7210748.114160e-09
0.7540721.7209288.229407e-09
0.7581541.7207838.345277e-09
0.7622591.7206388.461775e-09
0.7663851.7204958.578903e-09
0.7705341.7203538.696665e-09
0.7747051.7202128.815065e-09
0.7788991.7200728.934106e-09
0.7831161.7199339.053791e-09
0.7873551.7197959.174124e-09
0.7916171.7196579.295109e-09
0.7959031.7195219.416748e-09
0.8002111.7193859.539046e-09
0.8045431.7192519.662006e-09
0.8088991.7191179.785632e-09
0.8132781.7189849.909927e-09
0.817681.7188521.003489e-08
0.8221071.718721.016054e-08
0.8265571.718591.028686e-08
0.8310321.718461.041387e-08
0.8355311.7183311.054157e-08
0.8400541.7182031.066996e-08
0.8446021.7180751.079904e-08
0.8491741.7179481.092882e-08
0.8537711.7178221.105930e-08
0.8583931.7176961.119049e-08
0.863041.7175711.132239e-08
0.8677121.7174471.145501e-08
0.8724091.7173231.158834e-08
0.8771321.71721.172239e-08
0.881881.7170781.185717e-08
0.8866541.7169561.199268e-08
0.8914541.7168351.212892e-08
0.896281.7167141.226591e-08
0.9011321.7165931.240363e-08
0.9060111.7164741.254209e-08
0.9109151.7163541.268131e-08
0.9158461.7162361.282128e-08
0.9208041.7161171.296201e-08
0.9257891.7159991.310350e-08
0.9308011.7158821.324576e-08
0.935841.7157651.338878e-08
0.9409061.7156481.353258e-08
0.9461.7155321.367716e-08
0.9511211.7154161.382253e-08
0.956271.7153011.396867e-08
0.9614471.7151851.411561e-08
0.9666511.7150711.426335e-08
0.9718841.7149561.441188e-08
0.9771461.7148421.456122e-08
0.9824351.7147281.471137e-08
0.9877541.7146141.486233e-08
0.9931011.7145011.501411e-08
0.9984771.7143881.516671e-08
1.003881.7142751.532013e-08
1.009321.7141621.547439e-08
1.014781.714051.562948e-08
1.020271.7139371.578541e-08
1.02581.7138251.594219e-08
1.031351.7137131.609981e-08
1.036931.7136021.625829e-08
1.042551.713491.641762e-08
1.048191.7133781.657782e-08
1.053871.7132671.673888e-08
1.059571.7131551.690082e-08
1.061.7131471.691300e-08
1.065311.7130441.896686e-08
1.071071.7129332.119879e-08
1.076871.7128222.344281e-08
1.08271.712712.569898e-08
1.088561.7125992.796735e-08
1.094461.7124883.024801e-08
1.100381.7123773.254102e-08
1.106341.7122663.484644e-08
1.112331.7121553.716433e-08
1.118351.7120433.949478e-08
1.12441.7119324.183784e-08
1.130491.7118214.419359e-08
1.136611.7117094.656209e-08
1.142761.7115974.894341e-08
1.148951.7114865.133762e-08
1.155171.7113745.374480e-08
1.161421.7112625.616500e-08
1.167711.711155.859831e-08
1.174031.7110376.104479e-08
1.180391.7109256.350451e-08
1.186781.7108126.597755e-08
1.19321.7106996.846398e-08
1.199661.7105867.096387e-08
1.206161.7104727.347729e-08
1.212681.7103587.600431e-08
1.219251.7102447.854502e-08
1.225851.710138.109948e-08
1.232491.7100158.366777e-08
1.239161.70998.624997e-08
1.245871.7097858.884614e-08
1.252611.7096699.145636e-08
1.259391.7095539.408072e-08
1.266211.7094379.671929e-08
1.273061.709329.937213e-08
1.279961.7092031.020393e-07
1.286891.7090851.047210e-07
1.293851.7089671.074172e-07
1.300861.7088491.101279e-07
1.30791.708731.128534e-07
1.314981.708611.155935e-07
1.32211.708491.183486e-07
1.329251.708371.211185e-07
1.336451.7082481.239034e-07
1.343691.7081271.267034e-07
1.350961.7080051.295186e-07
1.358271.7078821.323490e-07
1.365631.7077581.351948e-07
1.373021.7076341.380559e-07
1.380451.707511.409325e-07
1.387921.7073841.438247e-07
1.395441.7072591.467326e-07
1.402991.7071321.496562e-07
1.410591.7070041.525956e-07
1.418221.7068761.555509e-07
1.42591.7067481.585222e-07
1.433621.7066181.615097e-07
1.441381.7064881.645133e-07
1.449181.7063571.675331e-07
1.457031.7062251.705693e-07
1.464921.7060921.736219e-07
1.472851.7059581.766911e-07
1.480821.7058241.797769e-07
1.488841.7056891.828794e-07
1.49691.7055521.859986e-07
1.5051.7054151.891348e-07
1.513151.7052771.922879e-07
1.521341.7051381.954581e-07
1.529581.7049981.986455e-07
1.531.7049911.988100e-07
1.537861.7048572.134547e-07
1.546181.7047152.289754e-07
1.554551.7045722.445800e-07
1.562971.7044282.602691e-07
1.571431.7042832.760432e-07
1.579931.7041372.919026e-07
1.588491.703993.078479e-07
1.597091.7038413.238796e-07
1.605731.7036923.399980e-07
1.614431.7035413.562036e-07
1.623161.7033893.724970e-07
1.631951.7032363.888786e-07
1.640791.7030824.053489e-07
1.649671.7029264.219084e-07
1.65861.7027694.385575e-07
1.667581.7026114.552967e-07
1.676611.7024514.721265e-07
1.685681.702294.890475e-07
1.694811.7021285.060600e-07
1.703981.7019655.231647e-07
1.713211.70185.403619e-07
1.722481.7016335.576523e-07
1.731811.7014655.750362e-07
1.741181.7012965.925142e-07
1.750611.7011256.100869e-07
1.760081.7009526.277547e-07
1.769611.7007786.455182e-07
1.779191.7006036.633778e-07
1.788821.7004266.813340e-07
1.798511.7002476.993875e-07
1.808241.7000667.175388e-07
1.818031.6998847.357883e-07
1.827871.69977.541365e-07
1.837771.6995147.725842e-07
1.847721.6993277.911316e-07
1.857721.6991388.097795e-07
1.867781.6989478.285283e-07
1.877891.6987548.473787e-07
1.888061.6985598.663311e-07
1.898281.6983628.853860e-07
1.908551.6981639.045442e-07
1.918881.6979639.238060e-07
1.929271.697769.431721e-07
1.939721.6975559.626431e-07
1.950221.6973499.822195e-07
1.960771.697141.001902e-06
1.971.6969571.019100e-06
1.971391.6969291.043914e-06
1.982061.6967161.234482e-06
1.992791.69651.426082e-06
2.003581.6962831.618720e-06
2.014431.6960631.812400e-06
2.025331.6958412.007128e-06
2.03631.6956162.202911e-06
2.047321.6953892.399753e-06
2.05841.695162.597662e-06
2.069551.6949282.796641e-06
2.080751.6946942.996698e-06
2.092011.6944573.197838e-06
2.103341.6942183.400066e-06
2.114721.6939763.603390e-06
2.126171.6937323.807814e-06
2.137681.6934844.013344e-06
2.149251.6932354.219988e-06
2.160891.6929824.427750e-06
2.172591.6927264.636636e-06
2.184351.6924684.846654e-06
2.196171.6922075.057808e-06
2.208061.6919435.270106e-06
2.220021.6916765.483553e-06
2.232031.6914055.698155e-06
2.244121.6911325.913919e-06
2.256271.6908566.130851e-06
2.268481.6905766.348958e-06
2.280761.6902946.568245e-06
2.293111.6900086.788720e-06
2.305521.6897197.010387e-06
2.3181.6894267.233255e-06
2.3251.6892617.358200e-06
2.330551.689137.706030e-06
2.343171.6888318.496527e-06
2.355851.6885289.291304e-06
2.368611.6882211.009038e-05
2.381431.6879111.089379e-05
2.394321.6875971.170154e-05
2.407281.687281.251367e-05
2.420311.6869581.333019e-05
2.433421.6866331.415114e-05
2.446591.6863041.497652e-05
2.459831.6859711.580638e-05
2.473151.6856341.664073e-05
2.486541.6852921.747959e-05
2.51.6849471.832300e-05

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
—