Optical constants

Refractive index of D-FK61-25 (CDGM)

D-FK61-25: 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
1.49653
Extinction coefficient k
9.36134e-09
Permittivity ε1
2.2396
Permittivity ε2
2.80190e-08
Absorption coefficient α
0.00200201 cm⁻¹
Penetration depth δ = λ/(2πk)
9.98996e+09 nm
Abbe number Vd
81.532
Chromatic dispersion dn/dλ
-0.0315178 µm⁻¹
Group index ng
1.51505
Group velocity dispersion
54.8673 fs²/mm
Dispersion parameter D
-299.33 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-FK61-25 (CDGM): D-FK61-25
cdgm_d_fk61_25 = ls.fetch_refractiveindex("specs", "CDGM-optical", "D-FK61-25", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgm_d_fk61_25.range_nm)  # (302, 2325) nm
eps = cdgm_d_fk61_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=0.894432499λ2λ2−0.00436678978+0.321652123λ2λ2−0.0141909741+0.748704285λ2λ2−149.771388

Valid from 0.302 to 2.325 µm.

Coefficients as stored
CiValue
C10.0
C20.894432499
C30.00436678978
C40.321652123
C50.0141909741
C60.748704285
C7149.771388

Comments and conditions

anneal rate:25°C/h

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: -2.45e-05 -2.09e-09 -6.72e-13 3.69e-07 2.37e-10 0.173
nd
1.496530
Vd
81.531772
glass code
497815
density
value: 3900
thermal expansion
value: 1.45e-05, temperature range: 243 343; value: 1.7e-05, temperature range: 293 573
dPgF
0.0321
resistance
climatic: 1.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = -9.71e-06 K⁻¹ at 633 nm, dn/dT = -9.90e-06 K⁻¹ at 1310 nm, dn/dT = -9.89e-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-FK61-25 (CDGM), D-FK61-25: n and k versus wavelength
λ (µm)nk
0.3021.5231142.620240e-06
0.3035491.5227212.490093e-06
0.3051061.5223322.359279e-06
0.306671.5219482.227794e-06
0.3082431.5215692.095635e-06
0.3098241.5211951.962798e-06
0.311.5211541.948000e-06
0.3114131.5208251.786992e-06
0.313011.520461.604987e-06
0.3146151.52011.422048e-06
0.3162291.5197431.238171e-06
0.317851.5193911.053350e-06
0.3194811.5190448.675825e-07
0.321.5189348.083900e-07
0.3211191.51877.612254e-07
0.3227661.5183616.918150e-07
0.3244211.5180266.220486e-07
0.3260851.5176955.519245e-07
0.3277571.5173684.814407e-07
0.3294381.5170444.105955e-07
0.331.5169383.869200e-07
0.3311281.5167253.650994e-07
0.3328261.516413.322428e-07
0.3345331.5160982.992176e-07
0.3362491.515792.660231e-07
0.3379731.5154852.326583e-07
0.3397061.5151851.991224e-07
0.341.5151341.934400e-07
0.3414481.5148871.785414e-07
0.34321.5145941.605300e-07
0.344961.5143031.424263e-07
0.3467291.5140161.242297e-07
0.3485071.5137331.059398e-07
0.351.5134999.058400e-08
0.3502941.5134538.936338e-08
0.3520911.5131768.191442e-08
0.3538971.5129027.442725e-08
0.3557121.5126326.690168e-08
0.3575361.5123655.933752e-08
0.3593691.51215.173457e-08
0.361.512014.912000e-08
0.3612121.5118394.603184e-08
0.3630651.5115814.131357e-08
0.3649271.5113263.657109e-08
0.3667981.5110743.180430e-08
0.368681.5108242.701305e-08
0.371.5106522.365000e-08
0.370571.5105782.333903e-08
0.3724711.5103342.230289e-08
0.3743811.5100932.126144e-08
0.3763011.5098552.021464e-08
0.3782311.5096191.916248e-08
0.381.5094071.819800e-08
0.3801711.5093871.815291e-08
0.382121.5091571.763799e-08
0.384081.5089291.712043e-08
0.386051.5087041.660022e-08
0.388031.5084821.607734e-08
0.391.5082641.555700e-08
0.390021.5082621.554514e-08
0.392021.5080441.434633e-08
0.394031.5078291.314136e-08
0.3960511.5076171.193022e-08
0.3980821.5074061.071287e-08
0.41.5072119.563600e-09
0.4001241.5071999.587363e-09
0.4021761.5069939.980575e-09
0.4042391.506791.037580e-08
0.4063121.5065891.077306e-08
0.4083961.506391.117235e-08
0.410491.5061931.157369e-08
0.4125951.5059991.197709e-08
0.4147111.5058061.238256e-08
0.4168381.5056161.279011e-08
0.4189761.5054281.319975e-08
0.421.5053391.339600e-08
0.4211251.5052421.323429e-08
0.4232841.5050581.292372e-08
0.4254551.5048761.261156e-08
0.4276371.5046961.229779e-08
0.429831.5045181.198242e-08
0.4320351.5043421.166543e-08
0.434251.5041671.134681e-08
0.4364771.5039951.102656e-08
0.4387161.5038251.070466e-08
0.441.5037281.052000e-08
0.4409661.5036561.036588e-08
0.4432271.5034891.000500e-08
0.44551.5033249.642275e-09
0.4477851.5031619.277685e-09
0.4500821.5029998.911226e-09
0.452391.5028398.542887e-09
0.454711.5026818.172659e-09
0.4570421.5025257.800532e-09
0.4593861.502377.426496e-09
0.461.502337.328500e-09
0.4617421.5022177.356248e-09
0.464111.5020657.393971e-09
0.466491.5019157.431887e-09
0.4688831.5017677.469998e-09
0.4712871.501627.508305e-09
0.4737041.5014757.546808e-09
0.4761341.5013317.585508e-09
0.4785751.5011897.624407e-09
0.481.5011077.647100e-09
0.481031.5010487.663505e-09
0.4834971.5009097.702804e-09
0.4859761.5007717.742304e-09
0.4884691.5006357.782007e-09
0.4909741.50057.821914e-09
0.4934921.5003667.862025e-09
0.4960231.5002347.902342e-09
0.4985671.5001037.942866e-09
0.51.500037.965700e-09
0.5011231.4999747.983599e-09
0.5036931.4998458.024545e-09
0.5062771.4997188.065700e-09
0.5088731.4995938.107067e-09
0.5114831.4994698.148646e-09
0.5141061.4993458.190438e-09
0.5167431.4992248.232444e-09
0.5193931.4991038.274666e-09
0.5220561.4989848.317104e-09
0.5247341.4988658.359760e-09
0.5274251.4987488.402635e-09
0.530131.4986338.445729e-09
0.5328491.4985188.489045e-09
0.5355811.4984048.532583e-09
0.5383281.4982928.576344e-09
0.5410891.4981818.620329e-09
0.5438641.498078.664540e-09
0.5466531.4979618.708978e-09
0.5494571.4978538.753644e-09
0.551.4978338.762300e-09
0.5522751.4977468.798538e-09
0.5551071.497648.843663e-09
0.5579541.4975358.889020e-09
0.5608151.4974328.934609e-09
0.5636911.4973298.980431e-09
0.5665821.4972279.026489e-09
0.5694881.4971269.072783e-09
0.5724091.4970269.119315e-09
0.5753441.4969279.166085e-09
0.5782951.4968299.213095e-09
0.5812611.4967329.260346e-09
0.5842421.4966369.307839e-09
0.5872381.496549.355576e-09
0.590251.4964469.403558e-09
0.5932771.4963529.451786e-09
0.5963191.496269.500261e-09
0.5993781.4961689.548985e-09
0.61.4961499.558900e-09
0.6024521.4960779.597934e-09
0.6055411.4959879.647128e-09
0.6086471.4958989.696574e-09
0.6117681.4958099.746274e-09
0.6149061.4957229.796228e-09
0.6180591.4956359.846439e-09
0.6212291.4955499.896908e-09
0.6244151.4954639.947635e-09
0.6276171.4953799.998622e-09
0.6308361.4952951.004987e-08
0.6340711.4952121.010138e-08
0.6373231.495131.015316e-08
0.6405921.4950481.020520e-08
0.6438771.4949681.025751e-08
0.6471791.4948881.031008e-08
0.651.494821.035500e-08
0.6504981.4948081.036294e-08
0.6538341.4947291.041612e-08
0.6571871.4946511.046957e-08
0.6605581.4945741.052329e-08
0.6639451.4944971.057729e-08
0.6673511.4944211.063157e-08
0.6707731.4943461.068612e-08
0.6742131.4942711.074096e-08
0.6776711.4941971.079607e-08
0.6811461.4941241.085147e-08
0.684641.4940511.090715e-08
0.6881511.4939781.096312e-08
0.691681.4939071.101938e-08
0.6952271.4938361.107592e-08
0.6987931.4937651.113276e-08
0.71.4937411.115200e-08
0.7023761.4936951.118986e-08
0.7059791.4936261.124724e-08
0.7095991.4935571.130492e-08
0.7132381.4934881.136289e-08
0.7168961.4934211.142116e-08
0.7205731.4933531.147973e-08
0.7242681.4932871.153860e-08
0.7279831.493221.159777e-08
0.7317161.4931551.165724e-08
0.7354691.4930891.171702e-08
0.7392411.4930251.177711e-08
0.7430321.4929611.183750e-08
0.7468431.4928971.189820e-08
0.7506731.4928331.195922e-08
0.7545231.4927711.202055e-08
0.7583921.4927081.208219e-08
0.7622821.4926461.214415e-08
0.7661911.4925851.220642e-08
0.770121.4925241.226902e-08
0.774071.4924631.233194e-08
0.778041.4924031.239517e-08
0.782031.4923431.245874e-08
0.7860411.4922841.252263e-08
0.7900721.4922251.258685e-08
0.7941241.4921661.265139e-08
0.7981961.4921081.271627e-08
0.81.4920821.274500e-08
0.802291.492051.278150e-08
0.8064051.4919931.284709e-08
0.810541.4919361.291301e-08
0.8146971.4918791.297927e-08
0.8188751.4918231.304587e-08
0.8230751.4917671.311281e-08
0.8272961.4917111.318010e-08
0.8315391.4916561.324773e-08
0.8358031.4916011.331571e-08
0.840091.4915461.338403e-08
0.8443981.4914911.345271e-08
0.8487291.4914371.352174e-08
0.851.4914221.354200e-08
0.8530821.4913841.359106e-08
0.8574571.491331.366071e-08
0.8618541.4912771.373072e-08
0.8662741.4912241.380108e-08
0.8707171.4911721.387181e-08
0.8751821.4911191.394290e-08
0.8796711.4910671.401436e-08
0.8841821.4910151.408618e-08
0.8887171.4909641.415837e-08
0.8932741.4909131.423093e-08
0.8978561.4908611.430386e-08
0.91.4908381.433800e-08
0.902461.4908111.437722e-08
0.9070881.490761.445099e-08
0.9117411.490711.452514e-08
0.9164161.490661.459968e-08
0.9211161.490611.467459e-08
0.925841.490561.474989e-08
0.9305881.4905111.482558e-08
0.9353611.4904611.490165e-08
0.9401581.4904121.497812e-08
0.944981.4903631.505497e-08
0.9498261.4903151.513222e-08
0.951.4903131.513500e-08
0.9546971.4902661.520978e-08
0.9595931.4902181.528772e-08
0.9645151.490171.536607e-08
0.9694611.4901221.544482e-08
0.9744331.4900741.552397e-08
0.979431.4900261.560353e-08
0.9844531.4899791.568350e-08
0.9895021.4899311.576387e-08
0.9945771.4898841.584466e-08
0.9996781.4898371.592587e-08
11.4898341.593100e-08
1.00481.489791.600755e-08
1.009961.4897431.608966e-08
1.015141.4896961.617219e-08
1.020341.489651.625514e-08
1.025581.4896031.633851e-08
1.030841.4895571.642232e-08
1.036121.489511.650655e-08
1.041441.4894641.659122e-08
1.046781.4894181.667632e-08
1.052151.4893721.676185e-08
1.057541.4893261.684783e-08
1.061.4893051.688700e-08
1.062971.489281.693425e-08
1.068421.4892341.702113e-08
1.07391.4891881.710844e-08
1.07941.4891431.719621e-08
1.084941.4890971.728443e-08
1.09051.4890511.737309e-08
1.09611.4890061.746222e-08
1.101721.488961.755180e-08
1.107371.4889141.764184e-08
1.113051.4888691.773234e-08
1.118761.4888231.782330e-08
1.124491.4887781.791474e-08
1.130261.4887331.800664e-08
1.136061.4886871.809901e-08
1.141881.4886421.819185e-08
1.147741.4885961.828518e-08
1.153621.4885511.837898e-08
1.159541.4885051.847326e-08
1.165491.488461.856802e-08
1.171471.4884141.866328e-08
1.177471.4883691.875902e-08
1.183511.4883231.885525e-08
1.189581.4882781.895197e-08
1.195681.4882321.904919e-08
1.21.48821.911800e-08
1.201811.4881861.914690e-08
1.207981.488141.924509e-08
1.214171.4880951.934377e-08
1.22041.4880491.944297e-08
1.226661.4880031.954267e-08
1.232951.4879571.964289e-08
1.239271.4879111.974361e-08
1.245631.4878641.984486e-08
1.252021.4878181.994662e-08
1.258441.4877722.004891e-08
1.264891.4877252.015172e-08
1.271381.4876792.025506e-08
1.27791.4876322.035893e-08
1.284451.4875852.046333e-08
1.291041.4875382.056826e-08
1.297661.4874912.067374e-08
1.304321.4874442.077975e-08
1.311011.4873972.088631e-08
1.317731.4873492.099342e-08
1.324491.4873022.110107e-08
1.331281.4872542.120928e-08
1.338111.4872062.131804e-08
1.344971.4871582.142736e-08
1.351871.487112.153724e-08
1.35881.4870612.164769e-08
1.365771.4870132.175870e-08
1.372771.4869642.187028e-08
1.379811.4869152.198243e-08
1.386891.4868662.209515e-08
1.3941.4868172.220846e-08
1.41.4867752.230400e-08
1.401151.4867672.232235e-08
1.408341.4867172.243682e-08
1.415561.4866672.255187e-08
1.422821.4866172.266752e-08
1.430121.4865672.278376e-08
1.437451.4865162.290060e-08
1.444821.4864652.301803e-08
1.452231.4864142.313607e-08
1.459681.4863622.325472e-08
1.467171.4863112.337397e-08
1.474691.4862592.349383e-08
1.482251.4862072.361431e-08
1.489861.4861542.373541e-08
1.49751.4861012.385712e-08
1.505181.4860482.397946e-08
1.51291.4859952.410243e-08
1.520651.4859422.422603e-08
1.528451.4858882.435027e-08
1.536291.4858332.447514e-08
1.544171.4857792.460065e-08
1.552091.4857242.472680e-08
1.560051.4856692.485360e-08
1.568051.4856132.498105e-08
1.576091.4855572.510916e-08
1.584181.4855012.523792e-08
1.59231.4854452.536735e-08
1.61.4853912.549000e-08
1.600471.4853882.549743e-08
1.608671.485332.562823e-08
1.616921.4852732.575969e-08
1.625221.4852152.589183e-08
1.633551.4851562.602465e-08
1.641931.4850972.615815e-08
1.650351.4850382.629233e-08
1.658811.4849782.642720e-08
1.667321.4849182.656277e-08
1.675871.4848582.669903e-08
1.684471.4847972.683598e-08
1.693111.4847362.697364e-08
1.701791.4846742.711201e-08
1.710521.4846122.725108e-08
1.719291.4845492.739087e-08
1.728111.4844862.753138e-08
1.736971.4844222.767260e-08
1.745881.4843582.781455e-08
1.754831.4842932.795723e-08
1.763831.4842282.810064e-08
1.772881.4841632.824479e-08
1.781971.4840972.838967e-08
1.791111.484032.853530e-08
1.81.4839652.867700e-08
1.800291.4839632.868167e-08
1.809531.4838952.882875e-08
1.818811.4838272.897658e-08
1.828131.4837582.912518e-08
1.837511.4836892.927453e-08
1.846931.4836192.942465e-08
1.856411.4835482.957554e-08
1.865931.4834772.972720e-08
1.87551.4834062.987964e-08
1.885111.4833343.003286e-08
1.894781.4832613.018687e-08
1.90451.4831873.034167e-08
1.914271.4831133.049726e-08
1.924081.4830383.065365e-08
1.933951.4829633.081085e-08
1.943871.4828873.096885e-08
1.953841.482813.112765e-08
1.963861.4827333.128728e-08
1.973931.4826553.144772e-08
1.984051.4825763.160898e-08
1.994231.4824973.177108e-08
21.4824523.186300e-08
2.004461.4824173.193400e-08
2.014741.4823363.209776e-08
2.025071.4822543.226236e-08
2.035461.4821723.242780e-08
2.045891.4820893.259409e-08
2.056391.4820053.276123e-08
2.066931.481923.292923e-08
2.077531.4818353.309810e-08
2.088191.4817493.326783e-08
2.09891.4816623.343843e-08
2.109661.4815743.360990e-08
2.120481.4814853.378225e-08
2.131361.4813963.395549e-08
2.142291.4813063.412962e-08
2.153271.4812153.430464e-08
2.164321.4811233.448055e-08
2.175421.481033.465737e-08
2.186571.4809363.483510e-08
2.197791.4808413.501373e-08
2.21.4808223.504900e-08
2.209061.4807463.692838e-08
2.220391.4806493.927913e-08
2.231771.4805524.164194e-08
2.243221.4804534.401686e-08
2.254721.4803544.640396e-08
2.266291.4802534.880331e-08
2.277911.4801525.121496e-08
2.289591.480055.363898e-08
2.301331.4799465.607543e-08
2.313141.4798425.852437e-08
2.3251.4797366.098588e-08

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
—