Optical constants

Refractive index of D-FK61A-25 (CDGM)

D-FK61A-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
1.49665
Extinction coefficient k
9.36134e-09
Permittivity ε1
2.23996
Permittivity ε2
2.80213e-08
Absorption coefficient α
0.00200201 cm⁻¹
Penetration depth δ = λ/(2πk)
9.98996e+09 nm
Abbe number Vd
81.549
Chromatic dispersion dn/dλ
-0.0315402 µm⁻¹
Group index ng
1.51518
Group velocity dispersion
54.5199 fs²/mm
Dispersion parameter D
-297.435 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-FK61A-25 (CDGM): D-FK61A-25
cdgm_d_fk61a_25 = ls.fetch_refractiveindex("specs", "CDGM-optical", "D-FK61A-25", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgm_d_fk61a_25.range_nm)  # (302, 2325) nm
eps = cdgm_d_fk61a_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=0.714581002λ2λ2−0.0108378966+0.502174967λ2λ2−0.00132310137+0.838296164λ2λ2−153.775939

Valid from 0.302 to 2.325 µm.

Coefficients as stored
CiValue
C10.0
C20.714581002
C30.0108378966
C40.502174967
C50.00132310137
C60.838296164
C7153.775939

Comments and conditions

anneal rate:25°C/h

Conditions

temperature
293 K

Properties

thermal dispersion
type: formula A, coefficients: -1.94e-05 2.54e-09 -2.83e-11 3.05e-07 -9.31e-11 0.242
nd
1.496650
Vd
81.549116
glass code
497816
glass status
standard
density
value: 3680
thermal expansion
value: 1.26e-05, temperature range: 243 343; value: 1.55e-05, temperature range: 293 573
dPgF
0.0309
resistance
climatic: 1.0

Thermo-optic coefficient

  • Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = -7.65e-06 K⁻¹ at 633 nm, dn/dT = -7.83e-06 K⁻¹ at 1310 nm, dn/dT = -7.83e-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-FK61A-25 (CDGM), D-FK61A-25: n and k versus wavelength
λ (µm)nk
0.3021.523163.197420e-06
0.3035491.5227682.980370e-06
0.3051061.5223822.762206e-06
0.306671.5219992.542923e-06
0.3082431.5216222.322516e-06
0.3098241.5212492.100979e-06
0.311.5212082.076300e-06
0.3114131.5208811.943522e-06
0.313011.5205181.793428e-06
0.3146151.5201581.642564e-06
0.3162291.5198031.490926e-06
0.317851.5194531.338511e-06
0.3194811.5191071.185314e-06
0.321.5189971.136500e-06
0.3211191.5187641.073429e-06
0.3227661.5184279.806103e-07
0.3244211.5180938.873154e-07
0.3260851.5177637.935420e-07
0.3277571.5174376.992877e-07
0.3294381.5171156.045500e-07
0.331.5170085.728900e-07
0.3311281.5167975.407682e-07
0.3328261.5164824.924002e-07
0.3345331.5161714.437842e-07
0.3362491.5158643.949189e-07
0.3379731.5155613.458029e-07
0.3397061.5152612.964351e-07
0.341.5152112.880700e-07
0.3414481.5149652.657647e-07
0.34321.5146722.387991e-07
0.344961.5143832.116953e-07
0.3467291.5140971.844524e-07
0.3485071.5138151.570698e-07
0.351.5135811.340800e-07
0.3502941.5135351.320953e-07
0.3520911.5132591.199834e-07
0.3538971.5129871.078093e-07
0.3557121.5127179.557281e-08
0.3575361.5124518.327357e-08
0.3593691.5121877.091125e-08
0.361.5120986.666000e-08
0.3612121.5119276.252633e-08
0.3630651.5116695.621066e-08
0.3649271.5114154.986259e-08
0.3667981.5111644.348198e-08
0.368681.5109153.706863e-08
0.371.5107433.256700e-08
0.370571.5106693.140074e-08
0.3724711.5104262.751484e-08
0.3743811.5101862.360901e-08
0.3763011.5099491.968314e-08
0.3782311.5097141.573715e-08
0.381.5095021.212000e-08
0.3801711.5094821.212545e-08
0.382121.5092521.218764e-08
0.384081.5090251.225016e-08
0.386051.5088011.231299e-08
0.388031.5085791.237615e-08
0.391.5083621.243900e-08
0.390021.508361.243963e-08
0.392021.5081431.250344e-08
0.394031.5079291.256757e-08
0.3960511.5077171.263204e-08
0.3980821.5075071.269683e-08
0.41.5073121.275800e-08
0.4001241.50731.274116e-08
0.4021761.5070951.246249e-08
0.4042391.5068921.218240e-08
0.4063121.5066921.190086e-08
0.4083961.5064931.161789e-08
0.410491.5062971.133346e-08
0.4125951.5061031.104757e-08
0.4147111.5059111.076022e-08
0.4168381.5057221.047139e-08
0.4189761.5055341.018108e-08
0.421.5054451.004200e-08
0.4211251.5053491.026646e-08
0.4232841.5051651.069754e-08
0.4254551.5049831.113084e-08
0.4276371.5048041.156636e-08
0.429831.5046261.200411e-08
0.4320351.5044511.244411e-08
0.434251.5042771.288636e-08
0.4364771.5041051.333088e-08
0.4387161.5039351.377768e-08
0.441.5038381.403400e-08
0.4409661.5037661.371019e-08
0.4432271.50361.295197e-08
0.44551.5034351.218986e-08
0.4477851.5032721.142384e-08
0.4500821.5031111.065389e-08
0.452391.5029529.879987e-09
0.454711.5027949.102119e-09
0.4570421.5026388.320262e-09
0.4593861.5024847.534395e-09
0.461.5024437.328500e-09
0.4617421.5023317.356248e-09
0.464111.502187.393971e-09
0.466491.502037.431887e-09
0.4688831.5018827.469998e-09
0.4712871.5017357.508305e-09
0.4737041.501597.546808e-09
0.4761341.5014477.585508e-09
0.4785751.5013057.624407e-09
0.481.5012237.647100e-09
0.481031.5011657.663505e-09
0.4834971.5010267.702804e-09
0.4859761.5008887.742304e-09
0.4884691.5007527.782007e-09
0.4909741.5006177.821914e-09
0.4934921.5004847.862025e-09
0.4960231.5003527.902342e-09
0.4985671.5002217.942866e-09
0.51.5001487.965700e-09
0.5011231.5000927.983599e-09
0.5036931.4999648.024545e-09
0.5062771.4998378.065700e-09
0.5088731.4997128.107067e-09
0.5114831.4995878.148646e-09
0.5141061.4994648.190438e-09
0.5167431.4993438.232444e-09
0.5193931.4992228.274666e-09
0.5220561.4991038.317104e-09
0.5247341.4989858.359760e-09
0.5274251.4988688.402635e-09
0.530131.4987528.445729e-09
0.5328491.4986388.489045e-09
0.5355811.4985248.532583e-09
0.5383281.4984128.576344e-09
0.5410891.4983018.620329e-09
0.5438641.4981918.664540e-09
0.5466531.4980828.708978e-09
0.5494571.4979748.753644e-09
0.551.4979538.762300e-09
0.5522751.4978678.798538e-09
0.5551071.4977618.843663e-09
0.5579541.4976568.889020e-09
0.5608151.4975528.934609e-09
0.5636911.4974498.980431e-09
0.5665821.4973479.026489e-09
0.5694881.4972469.072783e-09
0.5724091.4971469.119315e-09
0.5753441.4970479.166085e-09
0.5782951.4969499.213095e-09
0.5812611.4968529.260346e-09
0.5842421.4967569.307839e-09
0.5872381.496669.355576e-09
0.590251.4965669.403558e-09
0.5932771.4964729.451786e-09
0.5963191.496389.500261e-09
0.5993781.4962889.548985e-09
0.61.4962699.558900e-09
0.6024521.4961979.597934e-09
0.6055411.4961079.647128e-09
0.6086471.4960179.696574e-09
0.6117681.4959299.746274e-09
0.6149061.4958419.796228e-09
0.6180591.4957549.846439e-09
0.6212291.4956689.896908e-09
0.6244151.4955829.947635e-09
0.6276171.4954989.998622e-09
0.6308361.4954141.004987e-08
0.6340711.495331.010138e-08
0.6373231.4952481.015316e-08
0.6405921.4951661.020520e-08
0.6438771.4950851.025751e-08
0.6471791.4950051.031008e-08
0.651.4949371.035500e-08
0.6504981.4949251.036294e-08
0.6538341.4948461.041612e-08
0.6571871.4947681.046957e-08
0.6605581.494691.052329e-08
0.6639451.4946131.057729e-08
0.6673511.4945371.063157e-08
0.6707731.4944611.068612e-08
0.6742131.4943861.074096e-08
0.6776711.4943121.079607e-08
0.6811461.4942381.085147e-08
0.684641.4941651.090715e-08
0.6881511.4940921.096312e-08
0.691681.494021.101938e-08
0.6952271.4939481.107592e-08
0.6987931.4938771.113276e-08
0.71.4938541.115200e-08
0.7023761.4938071.118986e-08
0.7059791.4937371.124724e-08
0.7095991.4936681.130492e-08
0.7132381.4935991.136289e-08
0.7168961.4935311.142116e-08
0.7205731.4934631.147973e-08
0.7242681.4933961.153860e-08
0.7279831.4933291.159777e-08
0.7317161.4932631.165724e-08
0.7354691.4931971.171702e-08
0.7392411.4931321.177711e-08
0.7430321.4930671.183750e-08
0.7468431.4930031.189820e-08
0.7506731.4929391.195922e-08
0.7545231.4928761.202055e-08
0.7583921.4928131.208219e-08
0.7622821.492751.214415e-08
0.7661911.4926881.220642e-08
0.770121.4926271.226902e-08
0.774071.4925651.233194e-08
0.778041.4925051.239517e-08
0.782031.4924441.245874e-08
0.7860411.4923841.252263e-08
0.7900721.4923241.258685e-08
0.7941241.4922651.265139e-08
0.7981961.4922061.271627e-08
0.81.492181.274500e-08
0.802291.4921481.247123e-08
0.8064051.4920891.197933e-08
0.810541.4920321.148491e-08
0.8146971.4919741.098796e-08
0.8188751.4919171.048846e-08
0.8230751.491869.986393e-09
0.8272961.4918049.481754e-09
0.8315391.4917488.974527e-09
0.8358031.4916928.464699e-09
0.840091.4916367.952256e-09
0.8443981.4915817.437185e-09
0.8487291.4915266.919473e-09
0.851.491516.767500e-09
0.8530821.4914716.792035e-09
0.8574571.4914176.826869e-09
0.8618541.4913636.861882e-09
0.8662741.4913096.897074e-09
0.8707171.4912566.932447e-09
0.8751821.4912026.968001e-09
0.8796711.4911497.003738e-09
0.8841821.4910977.039657e-09
0.8887171.4910447.075761e-09
0.8932741.4909927.112051e-09
0.8978561.490947.148526e-09
0.91.4909167.165600e-09
0.902461.4908887.185183e-09
0.9070881.4908367.222024e-09
0.9117411.4907857.259054e-09
0.9164161.4907347.296274e-09
0.9211161.4906837.333685e-09
0.925841.4906327.371288e-09
0.9305881.4905817.409084e-09
0.9353611.4905317.447073e-09
0.9401581.4904817.485257e-09
0.944981.4904317.523637e-09
0.9498261.4903817.562214e-09
0.951.4903797.563600e-09
0.9546971.4903317.600998e-09
0.9595931.4902827.639982e-09
0.9645151.4902327.679165e-09
0.9694611.4901837.718549e-09
0.9744331.4901347.758135e-09
0.979431.4900857.797925e-09
0.9844531.4900367.837918e-09
0.9895021.4899877.878116e-09
0.9945771.4899397.918521e-09
0.9996781.489897.959133e-09
11.4898877.961700e-09
1.00481.4898427.999951e-09
1.009961.4897948.040979e-09
1.015141.4897458.082217e-09
1.020341.4896978.123667e-09
1.025581.4896498.165329e-09
1.030841.4896018.207205e-09
1.036121.4895548.249295e-09
1.041441.4895068.291602e-09
1.046781.4894588.334125e-09
1.052151.489418.376867e-09
1.057541.4893638.419827e-09
1.061.4893418.439400e-09
1.062971.4893158.463010e-09
1.068421.4892688.506415e-09
1.07391.489228.550043e-09
1.07941.4891738.593894e-09
1.084941.4891268.637970e-09
1.09051.4890788.682273e-09
1.09611.4890318.726802e-09
1.101721.4889848.771560e-09
1.107371.4889368.816548e-09
1.113051.4888898.861766e-09
1.118761.4888428.907216e-09
1.124491.4887958.952899e-09
1.130261.4887478.998817e-09
1.136061.48879.044970e-09
1.141881.4886539.091360e-09
1.147741.4886059.137987e-09
1.153621.4885589.184854e-09
1.159541.488519.231961e-09
1.165491.4884639.279310e-09
1.171471.4884159.326901e-09
1.177471.4883689.374737e-09
1.183511.488329.422818e-09
1.189581.4882729.471145e-09
1.195681.4882259.519720e-09
1.21.4881919.554100e-09
1.201811.4881779.568540e-09
1.207981.4881299.617599e-09
1.214171.4880819.666909e-09
1.22041.4880339.716472e-09
1.226661.4879859.766289e-09
1.232951.4879369.816362e-09
1.239271.4878889.866691e-09
1.245631.487849.917279e-09
1.252021.4877919.968126e-09
1.258441.4877421.001923e-08
1.264891.4876931.007060e-08
1.271381.4876441.012224e-08
1.27791.4875951.017414e-08
1.284451.4875461.022630e-08
1.291041.4874961.027873e-08
1.297661.4874471.033143e-08
1.304321.4873971.038440e-08
1.311011.4873471.043765e-08
1.317731.4872971.049116e-08
1.324491.4872471.054495e-08
1.331281.4871971.059902e-08
1.338111.4871461.065336e-08
1.344971.4870951.070798e-08
1.351871.4870441.076289e-08
1.35881.4869931.081807e-08
1.365771.4869421.087354e-08
1.372771.486891.092929e-08
1.379811.4868381.098532e-08
1.386891.4867861.104165e-08
1.3941.4867341.109826e-08
1.41.486691.114600e-08
1.401151.4866811.115517e-08
1.408341.4866281.121241e-08
1.415561.4865751.126994e-08
1.422821.4865221.132776e-08
1.430121.4864681.138588e-08
1.437451.4864151.144430e-08
1.444821.486361.150302e-08
1.452231.4863061.156204e-08
1.459681.4862511.162136e-08
1.467171.4861961.168098e-08
1.474691.4861411.174092e-08
1.482251.4860861.180115e-08
1.489861.486031.186170e-08
1.49751.4859731.192256e-08
1.505181.4859171.198373e-08
1.51291.485861.204522e-08
1.520651.4858031.210702e-08
1.528451.4857451.216913e-08
1.536291.4856871.223157e-08
1.544171.4856291.229432e-08
1.552091.4855711.235740e-08
1.560051.4855121.242080e-08
1.568051.4854521.248453e-08
1.576091.4853931.254858e-08
1.584181.4853321.261296e-08
1.59231.4852721.267767e-08
1.61.4852141.273900e-08
1.600471.4852111.274271e-08
1.608671.485151.280805e-08
1.616921.4850881.287372e-08
1.625221.4850261.293973e-08
1.633551.4849631.300607e-08
1.641931.48491.307276e-08
1.650351.4848361.313979e-08
1.658811.4847731.320716e-08
1.667321.4847081.327488e-08
1.675871.4846431.334294e-08
1.684471.4845781.341136e-08
1.693111.4845121.348012e-08
1.701791.4844461.354924e-08
1.710521.4843791.361871e-08
1.719291.4843111.368854e-08
1.728111.4842441.375873e-08
1.736971.4841751.382927e-08
1.745881.4841061.390018e-08
1.754831.4840371.397145e-08
1.763831.4839671.404309e-08
1.772881.4838961.411510e-08
1.781971.4838251.418747e-08
1.791111.4837531.426022e-08
1.81.4836831.433100e-08
1.800291.4836811.433333e-08
1.809531.4836081.440683e-08
1.818811.4835351.448070e-08
1.828131.4834611.455495e-08
1.837511.4833861.462958e-08
1.846931.4833111.470459e-08
1.856411.4832351.477999e-08
1.865931.4831581.485577e-08
1.87551.4830811.493194e-08
1.885111.4830031.500851e-08
1.894781.4829251.508546e-08
1.90451.4828451.516281e-08
1.914271.4827651.524056e-08
1.924081.4826851.531871e-08
1.933951.4826031.539725e-08
1.943871.4825211.547620e-08
1.953841.4824391.555556e-08
1.963861.4823551.563532e-08
1.973931.4822711.571549e-08
1.984051.4821861.579607e-08
1.994231.48211.587707e-08
21.4820511.592300e-08
2.004461.4820131.634922e-08
2.014741.4819261.733228e-08
2.025071.4818381.832039e-08
2.035461.4817491.931356e-08
2.045891.4816592.031183e-08
2.056391.4815682.131522e-08
2.066931.4814772.232376e-08
2.077531.4813852.333746e-08
2.088191.4812912.435637e-08
2.09891.4811972.538050e-08
2.109661.4811022.640988e-08
2.120481.4810062.744454e-08
2.131361.480912.848451e-08
2.142291.4808122.952981e-08
2.153271.4807133.058047e-08
2.164321.4806143.163653e-08
2.175421.4805133.269799e-08
2.186571.4804123.376490e-08
2.197791.4803093.483729e-08
2.21.4802893.504900e-08
2.209061.4802053.606040e-08
2.220391.4801013.732548e-08
2.231771.4799953.859704e-08
2.243221.4798893.987512e-08
2.254721.4797814.115976e-08
2.266291.4796724.245098e-08
2.277911.4795634.374883e-08
2.289591.4794524.505334e-08
2.301331.479344.636453e-08
2.313141.4792264.768245e-08
2.3251.4791124.900713e-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
—