Optical constants

Refractive index of N-SK4 (SCHOTT)

N-SK4: n,k 0.334–2.5 µm

Data
formula 2 + tabulated k
Range
0.334–2.5 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.334–2.5 µm
Refractive index n
1.61272
Extinction coefficient k
9.37538e-09
Permittivity ε1
2.60085
Permittivity ε2
3.02396e-08
Absorption coefficient α
0.00200501 cm⁻¹
Penetration depth δ = λ/(2πk)
9.97501e+09 nm
Abbe number Vd
58.634
Chromatic dispersion dn/dλ
-0.053945 µm⁻¹
Group index ng
1.64441
Group velocity dispersion
94.8091 fs²/mm
Dispersion parameter D
-517.234 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-SK4 (SCHOTT): N-SK4
schott_n_sk4 = ls.fetch_refractiveindex("specs", "SCHOTT-optical", "N-SK4", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(schott_n_sk4.range_nm)  # (334, 2500) nm
eps = schott_n_sk4.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=1.32993741λ2λ2−0.00716874107+0.228542996λ2λ2−0.0246455892+0.988465211λ2λ2−100.886364

Valid from 0.334 to 2.5 µm.

Coefficients as stored
CiValue
C10.0
C21.32993741
C30.00716874107
C40.228542996
C50.0246455892
C60.988465211
C7100.886364

Comments and conditions

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: 7.96e-07 1.3e-08 -1.31e-11 4.36e-07 6.01e-10 0.179
nd
1.61272
Vd
58.63
glass code
613586.354
glass status
standard
density
value: 3535
thermal expansion
value: 6.46e-06, temperature range: 243 343; value: 7.38e-06, temperature range: 293 573
dPgF
-0.0004
resistance
acid: 51.2; stain: 1.0; alkali: 2.0; climatic: 3.0; phosphate: 2.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 9.79e-07 K⁻¹ at 633 nm, dn/dT = 5.12e-07 K⁻¹ at 1310 nm, dn/dT = 4.74e-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 420 wavelengths, the same grid as the API and the library
N-SK4 (SCHOTT), N-SK4: n and k versus wavelength
λ (µm)nk
0.3341.6472791.711100e-06
0.3356891.6467261.588586e-06
0.3373871.6461791.465453e-06
0.3390931.645641.341697e-06
0.3408081.6451071.217315e-06
0.3425321.6445821.092304e-06
0.3442641.6440639.666611e-07
0.3460061.643558.403824e-07
0.3477561.6430447.134651e-07
0.3495141.6425455.859058e-07
0.351.6424085.506900e-07
0.3512821.6420515.221229e-07
0.3530591.6415644.825379e-07
0.3548441.6410834.427527e-07
0.3566391.6406084.027663e-07
0.3584431.6401393.625776e-07
0.3602561.6396753.221857e-07
0.3620781.6392182.815895e-07
0.3639091.6387652.407880e-07
0.3651.63852.164800e-07
0.365751.6383192.086160e-07
0.3675991.6378781.892077e-07
0.3694591.6374421.697012e-07
0.371.6373161.640200e-07
0.3713271.6370111.539021e-07
0.3732051.6365861.395840e-07
0.3750931.6361661.251935e-07
0.376991.635751.107302e-07
0.3788961.635349.619372e-08
0.381.6351068.778000e-08
0.3808131.6349358.476452e-08
0.3827391.6345357.761846e-08
0.3846741.6341397.043626e-08
0.386621.6337486.321773e-08
0.3885751.6333615.596269e-08
0.391.6330845.067700e-08
0.3905411.632984.967995e-08
0.3925161.6326024.603747e-08
0.3945011.6322294.237657e-08
0.3964961.6318613.869716e-08
0.3985021.6314973.499913e-08
0.41.6312283.223600e-08
0.4005171.6311373.173182e-08
0.4025431.6307812.975680e-08
0.4045791.6304292.777179e-08
0.4051.6303572.736100e-08
0.4066251.6300812.688025e-08
0.4086811.6297382.627178e-08
0.4107481.6293982.566024e-08
0.4128261.6290622.504560e-08
0.4149141.628732.442786e-08
0.4170121.6284022.380699e-08
0.4191211.6280782.318298e-08
0.421.6279442.292300e-08
0.4212411.6277572.299071e-08
0.4233721.627442.310696e-08
0.4255131.6271262.322379e-08
0.4276651.6268162.334121e-08
0.4298281.626512.345923e-08
0.4320021.6262072.357784e-08
0.4341871.6259072.369706e-08
0.4361.6256622.379600e-08
0.4363831.6256112.376944e-08
0.438591.6253182.361624e-08
0.4408081.6250282.346225e-08
0.4430371.6247412.330749e-08
0.4452781.6244582.315195e-08
0.447531.6241782.299562e-08
0.4497941.62392.283850e-08
0.4520681.6236262.268059e-08
0.4543551.6233552.252187e-08
0.4566531.6230872.236236e-08
0.4589621.6228222.220203e-08
0.461.6227042.213000e-08
0.4612841.6225592.183009e-08
0.4636171.62232.128499e-08
0.4659611.6220432.073713e-08
0.4683181.6217892.018649e-08
0.4706871.6215381.963308e-08
0.4730671.6212891.907686e-08
0.475461.6210431.851783e-08
0.4778641.62081.795597e-08
0.4802811.6205591.739127e-08
0.482711.6203211.682372e-08
0.4851521.6200851.625329e-08
0.4876051.6198521.567998e-08
0.4900721.6196221.510377e-08
0.492551.6193931.452465e-08
0.4950411.6191671.394260e-08
0.4975451.6189441.335760e-08
0.51.6187281.278400e-08
0.5000611.6187231.277856e-08
0.5025911.6185041.255466e-08
0.5051321.6182871.232963e-08
0.5076871.6180731.210346e-08
0.5102551.6178611.187615e-08
0.5128361.6176511.164769e-08
0.5154291.6174431.141807e-08
0.5180361.6172371.118729e-08
0.5206561.6170341.095534e-08
0.5232891.6168321.072222e-08
0.5259361.6166331.048792e-08
0.5285961.6164351.025244e-08
0.531271.616241.001576e-08
0.5339561.6160479.777892e-09
0.5366571.6158559.538817e-09
0.5393711.6156659.298533e-09
0.5420991.6154789.057033e-09
0.5448411.6152928.814312e-09
0.5461.6152148.711700e-09
0.5475971.6151088.737169e-09
0.5503661.6149268.781351e-09
0.553151.6147458.825757e-09
0.5559471.6145668.870387e-09
0.5587591.614398.915243e-09
0.5615851.6142148.960326e-09
0.5644251.6140419.005637e-09
0.567281.6138699.051177e-09
0.5701491.6136999.096947e-09
0.5730331.613539.142949e-09
0.5759311.6133649.189184e-09
0.5788441.6131989.235652e-09
0.581.6131339.254100e-09
0.5817711.6130359.282364e-09
0.5847141.6128729.329317e-09
0.5876711.6127129.376507e-09
0.5906431.6125539.423936e-09
0.593631.6123959.471605e-09
0.5966331.6122399.519515e-09
0.599651.6120849.567668e-09
0.6026831.6119319.616064e-09
0.6057311.6117799.664705e-09
0.6087951.6116299.713591e-09
0.6118741.6114799.762725e-09
0.6149681.6113329.812108e-09
0.6180791.6111859.861740e-09
0.621.6110969.892400e-09
0.6212051.611049.911632e-09
0.6243461.6108969.961791e-09
0.6275041.6107541.001220e-08
0.6306781.6106131.006287e-08
0.6338681.6104731.011380e-08
0.6370731.6103341.016498e-08
0.6402961.6101971.021642e-08
0.6435341.610061.026812e-08
0.6467891.6099251.032008e-08
0.650061.6097911.037231e-08
0.6533481.6096591.042479e-08
0.6566521.6095271.047755e-08
0.6599731.6093961.053057e-08
0.661.6093951.053100e-08
0.6633111.6092671.039852e-08
0.6666661.6091391.026429e-08
0.6700381.6090111.012937e-08
0.6734261.6088859.993780e-09
0.6768321.608769.857500e-09
0.6802551.6086369.720530e-09
0.6836961.6085139.582868e-09
0.6871541.6083919.444510e-09
0.6906291.608279.305452e-09
0.6941221.6081499.165691e-09
0.6976331.608039.025223e-09
0.71.6079518.930500e-09
0.7011611.6079128.978139e-09
0.7047071.6077959.123647e-09
0.7082711.6076789.269891e-09
0.7118541.6075639.416874e-09
0.7154541.6074489.564601e-09
0.7190721.6073359.713075e-09
0.7227091.6072229.862300e-09
0.7263641.607111.001228e-08
0.7300381.6069991.016302e-08
0.733731.6068881.031452e-08
0.7374411.6067791.046678e-08
0.7411711.606671.061982e-08
0.7449191.6065621.077363e-08
0.7486871.6064551.092822e-08
0.7524741.6063491.108359e-08
0.7562791.6062431.123975e-08
0.7601041.6061381.139669e-08
0.7639491.6060341.155443e-08
0.7678121.605931.171297e-08
0.7716961.6058281.187231e-08
0.7755991.6057261.203246e-08
0.7795211.6056241.219341e-08
0.7834641.6055231.235518e-08
0.7874261.6054231.251777e-08
0.7914091.6053241.268118e-08
0.7954111.6052251.284541e-08
0.7994341.6051271.301048e-08
0.8034781.6050291.317638e-08
0.8075411.6049331.334312e-08
0.8116251.6048361.351071e-08
0.815731.604741.367914e-08
0.8198561.6046451.384842e-08
0.8240031.6045511.401856e-08
0.828171.6044561.418956e-08
0.8323591.6043631.436143e-08
0.8365681.604271.453416e-08
0.8407991.6041771.470777e-08
0.8450521.6040851.488226e-08
0.8493261.6039941.505763e-08
0.8536211.6039031.523388e-08
0.8579391.6038121.541103e-08
0.8622781.6037221.558907e-08
0.8666391.6036321.576802e-08
0.8710221.6035431.594786e-08
0.8754271.6034541.612862e-08
0.8798551.6033661.631029e-08
0.8843051.6032781.649288e-08
0.8887771.6031911.667640e-08
0.8932721.6031031.686084e-08
0.897791.6030171.704622e-08
0.9023311.602931.723253e-08
0.9068951.6028441.741979e-08
0.9114811.6027591.760799e-08
0.9160911.6026731.779714e-08
0.9207241.6025881.798725e-08
0.9253811.6025041.817833e-08
0.9300611.6024191.837036e-08
0.9347651.6023361.856338e-08
0.9394931.6022521.875736e-08
0.9442451.6021681.895233e-08
0.949021.6020851.914828e-08
0.953821.6020021.934523e-08
0.9586441.601921.954317e-08
0.9634921.6018381.974211e-08
0.9683651.6017551.994206e-08
0.9732631.6016742.014302e-08
0.9781851.6015922.034499e-08
0.9831331.6015112.054799e-08
0.9881051.6014292.075201e-08
0.9931031.6013482.095707e-08
0.9981251.6012682.116316e-08
1.003171.6011872.137030e-08
1.008251.6011072.157848e-08
1.013351.6010262.178771e-08
1.018471.6009462.199801e-08
1.023621.6008662.220936e-08
1.02881.6007872.242179e-08
1.0341.6007072.263529e-08
1.039231.6006272.284987e-08
1.044491.6005482.306554e-08
1.049771.6004692.328229e-08
1.055081.6003892.350015e-08
1.061.6003162.370200e-08
1.060421.600312.378147e-08
1.065781.6002312.480411e-08
1.071171.6001522.583191e-08
1.076591.6000732.686492e-08
1.082031.5999942.790315e-08
1.087511.5999162.894663e-08
1.093011.5998372.999538e-08
1.098531.5997583.104945e-08
1.104091.5996793.210884e-08
1.109671.5996013.317359e-08
1.115291.5995223.424373e-08
1.120931.5994433.531927e-08
1.12661.5993643.640026e-08
1.132291.5992863.748672e-08
1.138021.5992073.857867e-08
1.143781.5991283.967614e-08
1.149561.5990494.077916e-08
1.155371.598974.188777e-08
1.161221.5988914.300197e-08
1.167091.5988124.412182e-08
1.172991.5987334.524733e-08
1.178931.5986544.637853e-08
1.184891.5985744.751545e-08
1.190881.5984954.865812e-08
1.19691.5984154.980657e-08
1.202961.5983365.096083e-08
1.209041.5982565.212093e-08
1.215161.5981765.328689e-08
1.22131.5980965.445875e-08
1.227481.5980155.563654e-08
1.233691.5979355.682029e-08
1.239931.5978545.801002e-08
1.24621.5977735.920577e-08
1.25251.5976926.040756e-08
1.258841.5976116.161544e-08
1.26521.5975296.282942e-08
1.27161.5974486.404955e-08
1.278031.5973666.527584e-08
1.28451.5972846.650834e-08
1.290991.5972016.774707e-08
1.297521.5971196.899207e-08
1.304091.5970367.024336e-08
1.310681.5969527.150098e-08
1.317311.5968697.276496e-08
1.323971.5967857.403533e-08
1.330671.5967017.531213e-08
1.33741.5966177.659539e-08
1.344161.5965327.788514e-08
1.350961.5964477.918141e-08
1.357791.5963618.048423e-08
1.364661.5962758.179365e-08
1.371561.5961898.310969e-08
1.37851.5961038.443238e-08
1.385471.5960168.576176e-08
1.392481.5959288.709787e-08
1.399521.5958418.844074e-08
1.40661.5957538.979039e-08
1.413711.5956649.114687e-08
1.420861.5955759.251022e-08
1.428051.5954869.388046e-08
1.435271.5953969.525762e-08
1.442531.5953059.664176e-08
1.449831.5952159.803289e-08
1.457161.5951239.943106e-08
1.464531.5950321.008363e-07
1.471941.5949391.022487e-07
1.479381.5948461.036681e-07
1.486861.5947531.050948e-07
1.494381.5946591.065287e-07
1.501941.5945651.079698e-07
1.509541.594471.094183e-07
1.517171.5943741.108740e-07
1.524851.5942781.123371e-07
1.531.5942141.133200e-07
1.532561.5941811.165015e-07
1.540311.5940841.261438e-07
1.54811.5939861.358350e-07
1.555931.5938881.455751e-07
1.56381.5937891.553645e-07
1.571711.5936891.652034e-07
1.579661.5935881.750921e-07
1.587651.5934871.850308e-07
1.595681.5933851.950198e-07
1.603751.5932832.050593e-07
1.611861.5931792.151495e-07
1.620011.5930752.252908e-07
1.62821.5929712.354834e-07
1.636441.5928652.457275e-07
1.644711.5927592.560234e-07
1.653031.5926522.663715e-07
1.661391.5925442.767718e-07
1.669791.5924362.872247e-07
1.678241.5923262.977306e-07
1.686731.5922163.082895e-07
1.695261.5921053.189019e-07
1.703831.5919933.295679e-07
1.712451.5918813.402879e-07
1.721111.5917673.510621e-07
1.729821.5916533.618907e-07
1.738561.5915373.727742e-07
1.747361.5914213.837127e-07
1.756191.5913043.947065e-07
1.765081.5911864.057559e-07
1.7741.5910674.168612e-07
1.782981.5909474.280227e-07
1.791991.5908264.392406e-07
1.801061.5907044.505153e-07
1.810171.590584.618469e-07
1.819321.5904564.732359e-07
1.828521.5903314.846825e-07
1.837771.5902054.961870e-07
1.847071.5900785.077497e-07
1.856411.5899495.193708e-07
1.86581.589825.310507e-07
1.875231.5896895.427897e-07
1.884721.5895585.545881e-07
1.894251.5894255.664462e-07
1.903831.5892915.783642e-07
1.913461.5891555.903425e-07
1.923141.5890196.023813e-07
1.932861.5888816.144811e-07
1.942641.5887426.266420e-07
1.952461.5886026.388645e-07
1.962341.588466.511488e-07
1.971.588356.606800e-07
1.972261.5883186.790207e-07
1.982241.5881747.598634e-07
1.992261.5880288.411150e-07
2.002341.5878819.227775e-07
2.012471.5877331.004853e-06
2.022641.5875841.087344e-06
2.032871.5874331.170251e-06
2.043161.587281.253579e-06
2.053491.5871271.337327e-06
2.063881.5869711.421499e-06
2.074311.5868151.506097e-06
2.08481.5866561.591123e-06
2.095351.5864971.676579e-06
2.105951.5863351.762467e-06
2.11661.5861721.848789e-06
2.12731.5860081.935548e-06
2.138061.5858422.022746e-06
2.148881.5856742.110384e-06
2.159741.5855042.198466e-06
2.170671.5853332.286994e-06
2.181641.585162.375969e-06
2.192681.5849862.465394e-06
2.203771.584812.555272e-06
2.214911.5846322.645604e-06
2.226121.5844522.736393e-06
2.237381.584272.827641e-06
2.248691.5840862.919351e-06
2.260061.5839013.011524e-06
2.271491.5837143.104164e-06
2.282981.5835243.197272e-06
2.294531.5833333.290851e-06
2.306131.583143.384903e-06
2.31781.5829453.479431e-06
2.3251.5828243.537800e-06
2.329521.5827483.639973e-06
2.34131.5825483.906262e-06
2.353141.5823474.173899e-06
2.365051.5821444.442889e-06
2.377011.5819384.713239e-06
2.389031.581734.984957e-06
2.401111.581525.258049e-06
2.413261.5813085.532522e-06
2.425461.5810935.808384e-06
2.437731.5808776.085641e-06
2.450061.5806576.364299e-06
2.462451.5804366.644368e-06
2.47491.5802126.925852e-06
2.487421.5799867.208761e-06
2.51.5797577.493100e-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
—