Optical constants

Refractive index of D-LAK70-25 (CDGM)

D-LAK70-25: n,k 0.302–2.325 µm

Data
formula 2 + tabulated k
Range
0.302–2.325 µm
Temperature
293 K
Licence
CC0-1.0

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.302–2.325 µm
Refractive index n
1.668
Extinction coefficient k
1.87414e-08
Permittivity ε1
2.78222
Permittivity ε2
6.25214e-08
Absorption coefficient α
0.00400803 cm⁻¹
Penetration depth δ = λ/(2πk)
4.98998e+09 nm
Abbe number Vd
55.296
Chromatic dispersion dn/dλ
-0.0623646 µm⁻¹
Group index ng
1.70464
Group velocity dispersion
109.254 fs²/mm
Dispersion parameter D
-596.041 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

# D-LAK70-25 (CDGM): D-LAK70-25
cdgm_d_lak70_25 = ls.fetch_refractiveindex("specs", "CDGM-optical", "D-LAK70-25", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgm_d_lak70_25.range_nm)  # (302, 2325) nm
eps = cdgm_d_lak70_25.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=0.615746796λ2λ2−0.000310601738+1.11671184λ2λ2−0.015811421+1.29436779λ2λ2−102.149797

Valid from 0.302 to 2.325 µm.

Coefficients as stored
CiValue
C10.0
C20.615746796
C30.000310601738
C41.11671184
C50.015811421
C61.29436779
C7102.149797

Comments and conditions

anneal rate:25°C/h

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: 2.1e-06 1.31e-08 -3.75e-11 5.42e-07 6.96e-10 0.177
nd
1.668000
Vd
55.295752
glass code
668553
density
value: 3350
thermal expansion
value: 7.3e-06, temperature range: 243 343; value: 9.1e-06, temperature range: 293 573
dPgF
-0.0067
resistance
climatic: 1.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 1.90e-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

CDGM Zemax catalog 2022-06 (obtained from http://www.cdgmgd.com); See also CDGM optical 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 431 wavelengths, the same grid as the API and the library
D-LAK70-25 (CDGM), D-LAK70-25: n and k versus wavelength
λ (µm)nk
0.3021.7226742.928640e-06
0.3035491.7218282.775958e-06
0.3051061.7209952.622493e-06
0.306671.7201732.468241e-06
0.3082431.7193622.313198e-06
0.3098241.7185622.157360e-06
0.311.7184742.140000e-06
0.3114131.7177732.039887e-06
0.313011.7169951.926717e-06
0.3146151.7162271.812967e-06
0.3162291.715471.698634e-06
0.317851.7147221.583714e-06
0.3194811.7139851.468205e-06
0.321.7137531.431400e-06
0.3211191.7132581.371867e-06
0.3227661.712541.284253e-06
0.3244211.7118311.196191e-06
0.3260851.7111321.107677e-06
0.3277571.7104421.018709e-06
0.3294381.7097629.292843e-07
0.331.7095378.994000e-07
0.3311281.709098.581498e-07
0.3328261.7084267.960367e-07
0.3345331.7077727.336050e-07
0.3362491.7071266.708531e-07
0.3379731.7064886.077794e-07
0.3397061.7058595.443822e-07
0.341.7057535.336400e-07
0.3414481.7052375.010967e-07
0.34321.7046244.617542e-07
0.344961.7040184.222100e-07
0.3467291.703423.824629e-07
0.3485071.702833.425120e-07
0.351.7023423.089700e-07
0.3502941.7022473.053624e-07
0.3520911.7016712.833464e-07
0.3538971.7011032.612175e-07
0.3557121.7005422.389751e-07
0.3575361.6999882.166187e-07
0.3593691.699441.941475e-07
0.361.6992541.864200e-07
0.3612121.69891.772768e-07
0.3630651.6983661.633072e-07
0.3649271.6978391.492660e-07
0.3667981.6973191.351527e-07
0.368681.6968051.209671e-07
0.371.6964491.110100e-07
0.370571.6962971.071100e-07
0.3724711.6957959.411527e-08
0.3743811.69538.105393e-08
0.3763011.694816.792561e-08
0.3782311.6943275.472996e-08
0.381.6938914.263400e-08
0.3801711.6938494.243864e-08
0.382121.6933774.020758e-08
0.384081.6929113.796509e-08
0.386051.6924513.571109e-08
0.388031.6919963.344553e-08
0.391.691553.119100e-08
0.390021.6915463.121809e-08
0.392021.6911023.395579e-08
0.394031.6906633.670754e-08
0.3960511.6902293.947339e-08
0.3980821.6898014.225343e-08
0.41.6894034.487800e-08
0.4001241.6893774.480801e-08
0.4021761.6889594.364994e-08
0.4042391.6885454.248594e-08
0.4063121.6881374.131596e-08
0.4083961.6877334.013998e-08
0.410491.6873343.895797e-08
0.4125951.6869393.776990e-08
0.4147111.6865493.657573e-08
0.4168381.6861643.537544e-08
0.4189761.6857833.416900e-08
0.421.6856033.359100e-08
0.4211251.6854063.328361e-08
0.4232841.6850343.269324e-08
0.4254551.6846663.209985e-08
0.4276371.6843033.150341e-08
0.429831.6839433.090391e-08
0.4320351.6835873.030134e-08
0.434251.6832362.969568e-08
0.4364771.6828892.908692e-08
0.4387161.6825452.847503e-08
0.441.6823512.812400e-08
0.4409661.6822062.800762e-08
0.4432271.681872.773511e-08
0.44551.6815382.746120e-08
0.4477851.6812092.718589e-08
0.4500821.6808852.690916e-08
0.452391.6805642.663102e-08
0.454711.6802462.635145e-08
0.4570421.6799332.607045e-08
0.4593861.6796222.578800e-08
0.461.6795422.571400e-08
0.4617421.6793152.547650e-08
0.464111.6790112.515361e-08
0.466491.6787112.482907e-08
0.4688831.6784142.450287e-08
0.4712871.678122.417499e-08
0.4737041.677832.384544e-08
0.4761341.6775432.351419e-08
0.4785751.6772582.318124e-08
0.481.6770942.298700e-08
0.481031.6769772.283031e-08
0.4834971.6766992.245496e-08
0.4859761.6764242.207769e-08
0.4884691.6761512.169848e-08
0.4909741.6758822.131733e-08
0.4934921.6756162.093422e-08
0.4960231.6753522.054914e-08
0.4985671.6750912.016210e-08
0.51.6749461.994400e-08
0.5011231.6748331.989003e-08
0.5036931.6745781.976656e-08
0.5062771.6743251.964247e-08
0.5088731.6740751.951773e-08
0.5114831.6738281.939236e-08
0.5141061.6735831.926634e-08
0.5167431.6733411.913968e-08
0.5193931.6731011.901237e-08
0.5220561.6728641.888441e-08
0.5247341.6726291.875578e-08
0.5274251.6723971.862650e-08
0.530131.6721671.849656e-08
0.5328491.6719391.836595e-08
0.5355811.6717141.823467e-08
0.5383281.6714911.810272e-08
0.5410891.671271.797009e-08
0.5438641.6710511.783678e-08
0.5466531.6708351.770278e-08
0.5494571.6706211.756810e-08
0.551.6705791.754200e-08
0.5522751.6704091.761456e-08
0.5551071.6701991.770491e-08
0.5579541.6699911.779573e-08
0.5608151.6697851.788701e-08
0.5636911.6695811.797876e-08
0.5665821.6693791.807098e-08
0.5694881.6691791.816367e-08
0.5724091.6689811.825684e-08
0.5753441.6687851.835048e-08
0.5782951.6685911.844461e-08
0.5812611.6683991.853922e-08
0.5842421.6682091.863431e-08
0.5872381.668021.872989e-08
0.590251.6678331.882596e-08
0.5932771.6676481.892253e-08
0.5963191.6674651.901959e-08
0.5993781.6672841.911715e-08
0.61.6672471.913700e-08
0.6024521.6671041.896068e-08
0.6055411.6669261.873847e-08
0.6086471.6667491.851512e-08
0.6117681.6665741.829063e-08
0.6149061.6664011.806498e-08
0.6180591.6662291.783818e-08
0.6212291.6660591.761021e-08
0.6244151.665891.738108e-08
0.6276171.6657231.715077e-08
0.6308361.6655581.691927e-08
0.6340711.6653931.668659e-08
0.6373231.6652311.645272e-08
0.6405921.665071.621765e-08
0.6438771.664911.598137e-08
0.6471791.6647511.574388e-08
0.651.6646181.554100e-08
0.6504981.6645941.555291e-08
0.6538341.6644381.563264e-08
0.6571871.6642841.571278e-08
0.6605581.6641311.579333e-08
0.6639451.6639791.587430e-08
0.6673511.6638291.595568e-08
0.6707731.663681.603748e-08
0.6742131.6635321.611969e-08
0.6776711.6633851.620233e-08
0.6811461.6632391.628540e-08
0.684641.6630951.636889e-08
0.6881511.6629521.645280e-08
0.691681.662811.653715e-08
0.6952271.6626691.662193e-08
0.6987931.6625291.670715e-08
0.71.6624821.673600e-08
0.7023761.662391.664115e-08
0.7059791.6622531.649739e-08
0.7095991.6621161.635289e-08
0.7132381.661981.620765e-08
0.7168961.6618461.606167e-08
0.7205731.6617131.591494e-08
0.7242681.661581.576745e-08
0.7279831.6614491.561921e-08
0.7317161.6613181.547020e-08
0.7354691.6611891.532044e-08
0.7392411.661061.516990e-08
0.7430321.6609321.501859e-08
0.7468431.6608051.486651e-08
0.7506731.660681.471365e-08
0.7545231.6605541.456000e-08
0.7583921.660431.440557e-08
0.7622821.6603071.425034e-08
0.7661911.6601851.409432e-08
0.770121.6600631.393749e-08
0.774071.6599421.377987e-08
0.778041.6598221.362143e-08
0.782031.6597031.346218e-08
0.7860411.6595841.330212e-08
0.7900721.6594661.314123e-08
0.7941241.6593491.297952e-08
0.7981961.6592331.281698e-08
0.81.6591821.274500e-08
0.802291.6591171.278150e-08
0.8064051.6590021.284709e-08
0.810541.6588881.291301e-08
0.8146971.6587751.297927e-08
0.8188751.6586621.304587e-08
0.8230751.6585491.311281e-08
0.8272961.6584381.318010e-08
0.8315391.6583271.324773e-08
0.8358031.6582161.331571e-08
0.840091.6581061.338403e-08
0.8443981.6579971.345271e-08
0.8487291.6578881.352174e-08
0.851.6578571.354200e-08
0.8530821.657781.359106e-08
0.8574571.6576721.366071e-08
0.8618541.6575651.373072e-08
0.8662741.6574591.380108e-08
0.8707171.6573531.387181e-08
0.8751821.6572471.394290e-08
0.8796711.6571421.401436e-08
0.8841821.6570371.408618e-08
0.8887171.6569331.415837e-08
0.8932741.6568291.423093e-08
0.8978561.6567261.430386e-08
0.91.6566781.433800e-08
0.902461.6566231.437722e-08
0.9070881.656521.445099e-08
0.9117411.6564181.452514e-08
0.9164161.6563171.459968e-08
0.9211161.6562151.467459e-08
0.925841.6561141.474989e-08
0.9305881.6560141.482558e-08
0.9353611.6559131.490165e-08
0.9401581.6558131.497812e-08
0.944981.6557131.505497e-08
0.9498261.6556141.513222e-08
0.951.655611.513500e-08
0.9546971.6555151.520978e-08
0.9595931.6554161.528772e-08
0.9645151.6553181.536607e-08
0.9694611.6552191.544482e-08
0.9744331.6551211.552397e-08
0.979431.6550231.560353e-08
0.9844531.6549261.568350e-08
0.9895021.6548281.576387e-08
0.9945771.6547311.584466e-08
0.9996781.6546341.592587e-08
11.6546281.593100e-08
1.00481.6545371.600755e-08
1.009961.6544411.608966e-08
1.015141.6543441.617219e-08
1.020341.6542481.625514e-08
1.025581.6541521.633851e-08
1.030841.6540551.642232e-08
1.036121.653961.650655e-08
1.041441.6538641.659122e-08
1.046781.6537681.667632e-08
1.052151.6536721.676185e-08
1.057541.6535771.684783e-08
1.061.6535331.688700e-08
1.062971.6534811.693425e-08
1.068421.6533851.702113e-08
1.07391.653291.710844e-08
1.07941.6531951.719621e-08
1.084941.6530991.728443e-08
1.09051.6530041.737309e-08
1.09611.6529081.746222e-08
1.101721.6528131.755180e-08
1.107371.6527171.764184e-08
1.113051.6526221.773234e-08
1.118761.6525261.782330e-08
1.124491.6524311.791474e-08
1.130261.6523351.800664e-08
1.136061.6522391.809901e-08
1.141881.6521431.819185e-08
1.147741.6520471.828518e-08
1.153621.6519511.837898e-08
1.159541.6518551.847326e-08
1.165491.6517591.856802e-08
1.171471.6516621.866328e-08
1.177471.6515661.875902e-08
1.183511.6514691.885525e-08
1.189581.6513721.895197e-08
1.195681.6512751.904919e-08
1.21.6512061.911800e-08
1.201811.6511771.914690e-08
1.207981.651081.924509e-08
1.214171.6509821.934377e-08
1.22041.6508841.944297e-08
1.226661.6507861.954267e-08
1.232951.6506871.964289e-08
1.239271.6505881.974361e-08
1.245631.6504891.984486e-08
1.252021.650391.994662e-08
1.258441.650292.004891e-08
1.264891.650192.015172e-08
1.271381.650092.025506e-08
1.27791.6499892.035893e-08
1.284451.6498882.046333e-08
1.291041.6497872.056826e-08
1.297661.6496852.067374e-08
1.304321.6495832.077975e-08
1.311011.6494812.088631e-08
1.317731.6493782.099342e-08
1.324491.6492752.110107e-08
1.331281.6491712.120928e-08
1.338111.6490672.131804e-08
1.344971.6489622.142736e-08
1.351871.6488572.153724e-08
1.35881.6487522.164769e-08
1.365771.6486462.175870e-08
1.372771.6485392.187028e-08
1.379811.6484322.198243e-08
1.386891.6483242.209515e-08
1.3941.6482162.220846e-08
1.41.6481252.230400e-08
1.401151.6481082.232235e-08
1.408341.6479982.243682e-08
1.415561.6478892.255187e-08
1.422821.6477782.266752e-08
1.430121.6476672.278376e-08
1.437451.6475562.290060e-08
1.444821.6474432.301803e-08
1.452231.6473312.313607e-08
1.459681.6472172.325472e-08
1.467171.6471032.337397e-08
1.474691.6469882.349383e-08
1.482251.6468722.361431e-08
1.489861.6467562.373541e-08
1.49751.6466392.385712e-08
1.505181.6465212.397946e-08
1.51291.6464032.410243e-08
1.520651.6462842.422603e-08
1.528451.6461642.435027e-08
1.536291.6460432.447514e-08
1.544171.6459212.460065e-08
1.552091.6457992.472680e-08
1.560051.6456762.485360e-08
1.568051.6455512.498105e-08
1.576091.6454262.510916e-08
1.584181.6453012.523792e-08
1.59231.6451742.536735e-08
1.61.6450542.549000e-08
1.600471.6450462.563162e-08
1.608671.6449182.812329e-08
1.616921.6447883.062773e-08
1.625221.6446583.314502e-08
1.633551.6445263.567522e-08
1.641931.6443943.821840e-08
1.650351.644264.077461e-08
1.658811.6441264.334394e-08
1.667321.643994.592645e-08
1.675871.6438544.852219e-08
1.684471.6437165.113126e-08
1.693111.6435775.375370e-08
1.701791.6434385.638959e-08
1.710521.6432975.903900e-08
1.719291.6431556.170200e-08
1.728111.6430116.437865e-08
1.736971.6428676.706903e-08
1.745881.6427216.977321e-08
1.754831.6425747.249126e-08
1.763831.6424267.522325e-08
1.772881.6422777.796924e-08
1.781971.6421278.072932e-08
1.791111.6419758.350356e-08
1.81.6418278.620300e-08
1.800291.6418228.664352e-08
1.809531.6416671.005125e-07
1.818811.6415111.144526e-07
1.828131.6413541.284641e-07
1.837511.6411961.425476e-07
1.846931.6410361.567032e-07
1.856411.6408741.709315e-07
1.865931.6407111.852327e-07
1.87551.6405471.996073e-07
1.885111.6403812.140556e-07
1.894781.6402142.285780e-07
1.90451.6400452.431749e-07
1.914271.6398752.578466e-07
1.924081.6397032.725936e-07
1.933951.6395292.874162e-07
1.943871.6393543.023148e-07
1.953841.6391783.172899e-07
1.963861.6389993.323417e-07
1.973931.6388193.474707e-07
1.984051.6386373.626773e-07
1.994231.6384533.779619e-07
21.6383493.866300e-07
2.004461.6382684.071669e-07
2.014741.6380814.545351e-07
2.025071.6378925.021462e-07
2.035461.6377015.500015e-07
2.045891.6375095.981022e-07
2.056391.6373146.464496e-07
2.066931.6371186.950449e-07
2.077531.6369197.438895e-07
2.088191.6367197.929846e-07
2.09891.6365178.423314e-07
2.109661.6363128.919314e-07
2.120481.6361069.417857e-07
2.131361.6358989.918956e-07
2.142291.6356871.042263e-06
2.153271.6354741.092888e-06
2.164321.6352591.143773e-06
2.175421.6350421.194919e-06
2.186571.6348231.246327e-06
2.197791.6346021.297999e-06
2.21.6345581.308200e-06
2.209061.6343781.509389e-06
2.220391.6341521.761039e-06
2.231771.6339232.013979e-06
2.243221.6336922.268216e-06
2.254721.6334592.523757e-06
2.266291.6332232.780609e-06
2.277911.6329853.038778e-06
2.289591.6327443.298271e-06
2.301331.6325013.559095e-06
2.313141.6322553.821257e-06
2.3251.6320074.084763e-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
—