Optical constants

Refractive index of K4A (CDGM)

K4A: n,k 0.365–2.325 µm

Data: formula 2 + tabulated k
Range: 0.365–2.325 µm
Temperature: 293 K
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.50802
Extinction coefficient k: 2.34385e-08

Permittivity ε₁: 2.27412
Permittivity ε₂: 7.06913e-08

Absorption coefficient α: 0.00501254 cm⁻¹
Penetration depth δ = λ/(2πk): 3.98999e+09 nm

Abbe number V_d: 61.053
Chromatic dispersion dn/dλ: -0.0430982 µm⁻¹

Group index n_g: 1.53334
Group velocity dispersion: 73.2855 fs²/mm

Dispersion parameter D: -399.811 ps/(nm·km)
Photon energy: 2.11001 eV

ε = (n + ik)², α = 4πk/λ, n_g = 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

# K4A (CDGM): K4A
cdgm_k4a = ls.fetch_refractiveindex("specs", "CDGM-optical", "K4A", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgm_k4a.range_nm)  # (365, 2325) nm
eps = cdgm_k4a.eps([633])  # complex permittivity

Downloads the original record once (pinned to the imported snapshot) and caches it.

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_d06254bb1aa0/lightsmith"
cdgm_k4a = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(cdgm_k4a.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (cdgm-k4a/cdgm).

# ... load cdgm_k4a as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=cdgm_k4a)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=1000, num=81),
)
res = ls.solve(sim)  # exact Mie for a sphere
print(res.q_ext)     # extinction efficiency at each wavelength

Same spec runs with DDA, FDTD, BEM or T-matrix: ls.compare(sim, ["mie", "dda"]).

Materials guide Open a sphere of it in Studio Quick start Ask the community

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

n^{2} - 1 = \frac{0.749532263 λ^{2}}{λ^{2} - 0.0148033503} + \frac{0.494866234 λ^{2}}{λ^{2} + 0.000264092219} + \frac{0.96016866 λ^{2}}{λ^{2} - 95.7190154}

Valid from 0.365 to 2.325 µm.

Coefficients as stored

C_i	Value
C1	0.0
C2	0.749532263
C3	0.0148033503
C4	0.494866234
C5	-0.000264092219
C6	0.96016866
C7	95.7190154

Comments and conditions

Conditions

temperature: 293 K

Properties

thermal dispersion: type: formula A, coefficients: 7.37e-06 2.2e-08 -6.81e-12 4.56e-07 4.32e-10 0.199
nd: 1.508020
Vd: 61.052897
glass code: 508611
density: value: 2430
thermal expansion: value: 4.7e-06, temperature range: 243 343; value: 5.2e-06, temperature range: 293 573
dPgF: -0.0028
resistance: climatic: 1.0

Thermo-optic coefficient

Schott thermal-dispersion model (reference temperature 293.0 K): dn/dT = 3.64e-06 K⁻¹ at 633 nm, dn/dT = 3.15e-06 K⁻¹ at 1310 nm, dn/dT = 3.10e-06 K⁻¹ at 1550 nm

References

CDGM Zemax catalog 2022-06 (obtained from http://www.cdgmgd.com)
See also CDGM optical glass data sheets

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 425 wavelengths, the same grid as the API and the library

CSV comma separated TXT tab separated YAML n, k Full database record original YAML All quantities CSV JSON metadata

K4A (CDGM), K4A: n and k versus wavelength
λ (µm)	n	k
0.365	1.528325	2.580100e-07
0.366698	1.528005	2.322621e-07
0.368403	1.52769	2.063945e-07
0.37	1.527398	1.821800e-07
0.370117	1.527377	1.814564e-07
0.371838	1.527068	1.708035e-07
0.373568	1.526763	1.601011e-07
0.375306	1.526461	1.493489e-07
0.377051	1.526162	1.385467e-07
0.378805	1.525866	1.276943e-07
0.38	1.525667	1.203000e-07
0.380567	1.525574	1.175735e-07
0.382337	1.525284	1.090618e-07
0.384116	1.524998	1.005105e-07
0.385902	1.524715	9.191938e-08
0.387697	1.524435	8.328833e-08
0.3895	1.524158	7.461712e-08
0.39	1.524082	7.221500e-08
0.391312	1.523884	6.947604e-08
0.393132	1.523613	6.567672e-08
0.394961	1.523345	6.185973e-08
0.396798	1.52308	5.802498e-08
0.398644	1.522817	5.417239e-08
0.4	1.522627	5.134100e-08
0.400498	1.522558	5.115166e-08
0.402361	1.522301	5.044313e-08
0.404232	1.522046	4.973130e-08
0.406112	1.521795	4.901616e-08
0.408001	1.521546	4.829769e-08
0.409899	1.5213	4.757588e-08
0.411806	1.521056	4.685071e-08
0.413721	1.520815	4.612218e-08
0.415645	1.520576	4.539025e-08
0.417579	1.52034	4.465492e-08
0.419521	1.520106	4.391616e-08
0.42	1.520049	4.373400e-08
0.421472	1.519874	4.336553e-08
0.423433	1.519645	4.287494e-08
0.425402	1.519419	4.238207e-08
0.427381	1.519195	4.188690e-08
0.429369	1.518973	4.138943e-08
0.431366	1.518753	4.088965e-08
0.433372	1.518535	4.038754e-08
0.435388	1.51832	3.988310e-08
0.437413	1.518107	3.937631e-08
0.439448	1.517896	3.886716e-08
0.44	1.517839	3.872900e-08
0.441492	1.517687	3.830865e-08
0.443545	1.51748	3.773007e-08
0.445609	1.517275	3.714880e-08
0.447681	1.517073	3.656482e-08
0.449764	1.516872	3.597813e-08
0.451856	1.516674	3.538871e-08
0.453957	1.516477	3.479655e-08
0.456069	1.516282	3.420163e-08
0.45819	1.516089	3.360394e-08
0.46	1.515927	3.309400e-08
0.460321	1.515899	3.305524e-08
0.462462	1.51571	3.279691e-08
0.464613	1.515522	3.253739e-08
0.466775	1.515337	3.227665e-08
0.468946	1.515154	3.201471e-08
0.471127	1.514972	3.175154e-08
0.473318	1.514792	3.148716e-08
0.47552	1.514614	3.122154e-08
0.477732	1.514437	3.095468e-08
0.479954	1.514262	3.068659e-08
0.48	1.514259	3.068100e-08
0.482186	1.514089	3.038249e-08
0.484429	1.513918	3.007623e-08
0.486682	1.513748	2.976855e-08
0.488946	1.51358	2.945944e-08
0.49122	1.513413	2.914889e-08
0.493505	1.513248	2.883690e-08
0.4958	1.513085	2.852346e-08
0.498107	1.512923	2.820855e-08
0.5	1.512791	2.795000e-08
0.500423	1.512762	2.789910e-08
0.502751	1.512603	2.761927e-08
0.505089	1.512446	2.733814e-08
0.507439	1.51229	2.705571e-08
0.509799	1.512135	2.677195e-08
0.51217	1.511982	2.648688e-08
0.514553	1.51183	2.620049e-08
0.516946	1.51168	2.591276e-08
0.51935	1.511531	2.562369e-08
0.521766	1.511384	2.533328e-08
0.524193	1.511237	2.504152e-08
0.526631	1.511092	2.474840e-08
0.529081	1.510949	2.445391e-08
0.531542	1.510807	2.415806e-08
0.534014	1.510666	2.386083e-08
0.536498	1.510526	2.356222e-08
0.538993	1.510387	2.326222e-08
0.5415	1.51025	2.296082e-08
0.544019	1.510114	2.265803e-08
0.546549	1.509979	2.235382e-08
0.549092	1.509845	2.204820e-08
0.55	1.509798	2.193900e-08
0.551646	1.509713	2.200463e-08
0.554212	1.509581	2.210696e-08
0.556789	1.509451	2.220976e-08
0.559379	1.509322	2.231304e-08
0.561981	1.509194	2.241680e-08
0.564595	1.509067	2.252105e-08
0.567221	1.508941	2.262578e-08
0.569859	1.508817	2.273100e-08
0.57251	1.508693	2.283670e-08
0.575173	1.50857	2.294290e-08
0.577848	1.508449	2.304959e-08
0.580536	1.508328	2.315678e-08
0.583236	1.508208	2.326447e-08
0.585949	1.50809	2.337265e-08
0.588675	1.507972	2.348134e-08
0.591413	1.507856	2.359054e-08
0.594164	1.50774	2.370024e-08
0.596927	1.507625	2.381046e-08
0.599704	1.507511	2.392119e-08
0.6	1.507499	2.393300e-08
0.602493	1.507398	2.377339e-08
0.605296	1.507286	2.359398e-08
0.608111	1.507175	2.341373e-08
0.61094	1.507065	2.323265e-08
0.613781	1.506956	2.305073e-08
0.616636	1.506847	2.286796e-08
0.619504	1.506739	2.268434e-08
0.622386	1.506633	2.249986e-08
0.625281	1.506527	2.231453e-08
0.628189	1.506421	2.212833e-08
0.631111	1.506317	2.194127e-08
0.634047	1.506213	2.175334e-08
0.636996	1.506111	2.156454e-08
0.639959	1.506009	2.137485e-08
0.642935	1.505907	2.118429e-08
0.645926	1.505807	2.099283e-08
0.64893	1.505707	2.080049e-08
0.65	1.505672	2.073200e-08
0.651949	1.505608	2.079412e-08
0.654981	1.50551	2.089079e-08
0.658028	1.505412	2.098792e-08
0.661088	1.505315	2.108549e-08
0.664163	1.505219	2.118352e-08
0.667252	1.505123	2.128201e-08
0.670356	1.505029	2.138095e-08
0.673474	1.504934	2.148035e-08
0.676607	1.504841	2.158022e-08
0.679754	1.504748	2.168055e-08
0.682915	1.504656	2.178135e-08
0.686092	1.504564	2.188261e-08
0.689283	1.504473	2.198435e-08
0.692489	1.504382	2.208656e-08
0.69571	1.504293	2.218924e-08
0.698946	1.504203	2.229241e-08
0.7	1.504174	2.232600e-08
0.702197	1.504115	2.239609e-08
0.705463	1.504027	2.250028e-08
0.708745	1.503939	2.260496e-08
0.712041	1.503852	2.271012e-08
0.715353	1.503766	2.281577e-08
0.718681	1.50368	2.292191e-08
0.722023	1.503594	2.302855e-08
0.725382	1.503509	2.313568e-08
0.728756	1.503425	2.324331e-08
0.732146	1.503341	2.335144e-08
0.735551	1.503258	2.346008e-08
0.738972	1.503175	2.356922e-08
0.742409	1.503093	2.367886e-08
0.745863	1.503011	2.378902e-08
0.749332	1.502929	2.389969e-08
0.752817	1.502848	2.401087e-08
0.756319	1.502768	2.412257e-08
0.759837	1.502687	2.423479e-08
0.763371	1.502608	2.434754e-08
0.766922	1.502528	2.446080e-08
0.770489	1.50245	2.457460e-08
0.774073	1.502371	2.468892e-08
0.777673	1.502293	2.480378e-08
0.78129	1.502215	2.491916e-08
0.784924	1.502138	2.503509e-08
0.788575	1.502061	2.515156e-08
0.792243	1.501985	2.526856e-08
0.795928	1.501908	2.538611e-08
0.79963	1.501833	2.550421e-08
0.8	1.501825	2.551600e-08
0.80335	1.501757	2.516809e-08
0.807086	1.501682	2.478000e-08
0.81084	1.501607	2.439011e-08
0.814612	1.501533	2.399840e-08
0.818401	1.501459	2.360487e-08
0.822208	1.501385	2.320952e-08
0.826032	1.501311	2.281232e-08
0.829874	1.501238	2.241327e-08
0.833734	1.501165	2.201237e-08
0.837612	1.501092	2.160960e-08
0.841508	1.50102	2.120496e-08
0.845422	1.500948	2.079844e-08
0.849355	1.500876	2.039003e-08
0.85	1.500864	2.032300e-08
0.853305	1.500804	2.040200e-08
0.857274	1.500733	2.049685e-08
0.861262	1.500662	2.059215e-08
0.865268	1.500591	2.068790e-08
0.869292	1.50052	2.078409e-08
0.873336	1.50045	2.088072e-08
0.877398	1.50038	2.097781e-08
0.881479	1.50031	2.107535e-08
0.885579	1.50024	2.117334e-08
0.889698	1.50017	2.127179e-08
0.893836	1.500101	2.137069e-08
0.897994	1.500032	2.147006e-08
0.9	1.499999	2.151800e-08
0.902171	1.499963	2.156993e-08
0.906367	1.499894	2.167030e-08
0.910583	1.499825	2.177114e-08
0.914818	1.499757	2.187245e-08
0.919073	1.499688	2.197424e-08
0.923348	1.49962	2.207649e-08
0.927643	1.499552	2.217922e-08
0.931958	1.499484	2.228243e-08
0.936293	1.499416	2.238612e-08
0.940648	1.499348	2.249030e-08
0.945023	1.499281	2.259495e-08
0.949419	1.499213	2.270009e-08
0.95	1.499204	2.271400e-08
0.953835	1.499146	2.280565e-08
0.958271	1.499079	2.291169e-08
0.962729	1.499011	2.301821e-08
0.967207	1.498944	2.312524e-08
0.971705	1.498877	2.323276e-08
0.976225	1.49881	2.334078e-08
0.980766	1.498743	2.344930e-08
0.985328	1.498676	2.355833e-08
0.989911	1.498609	2.366787e-08
0.994515	1.498543	2.377791e-08
0.999141	1.498476	2.388847e-08
1	1.498464	2.390900e-08
1.00379	1.498409	2.399960e-08
1.00846	1.498343	2.411127e-08
1.01315	1.498276	2.422345e-08
1.01786	1.498209	2.433616e-08
1.02259	1.498143	2.444939e-08
1.02735	1.498076	2.456315e-08
1.03213	1.498009	2.467744e-08
1.03693	1.497943	2.479226e-08
1.04175	1.497876	2.490761e-08
1.0466	1.497809	2.502350e-08
1.05147	1.497743	2.513993e-08
1.05636	1.497676	2.525690e-08
1.06	1.497626	2.534400e-08
1.06127	1.497609	2.528745e-08
1.06621	1.497542	2.506793e-08
1.07117	1.497475	2.484738e-08
1.07615	1.497408	2.462581e-08
1.08115	1.497341	2.440321e-08
1.08618	1.497274	2.417957e-08
1.09124	1.497207	2.395489e-08
1.09631	1.49714	2.372917e-08
1.10141	1.497072	2.350239e-08
1.10653	1.497005	2.327457e-08
1.11168	1.496937	2.304568e-08
1.11685	1.496869	2.281572e-08
1.12205	1.496802	2.258470e-08
1.12727	1.496734	2.235261e-08
1.13251	1.496666	2.211943e-08
1.13778	1.496598	2.188517e-08
1.14307	1.496529	2.164982e-08
1.14839	1.496461	2.141337e-08
1.15373	1.496392	2.117583e-08
1.15909	1.496323	2.093718e-08
1.16448	1.496254	2.069742e-08
1.1699	1.496185	2.045654e-08
1.17534	1.496116	2.021455e-08
1.18081	1.496046	1.997143e-08
1.1863	1.495977	1.972717e-08
1.19182	1.495907	1.948179e-08
1.19736	1.495837	1.923526e-08
1.2	1.495803	1.911800e-08
1.20293	1.495766	2.247169e-08
1.20853	1.495696	2.887017e-08
1.21415	1.495625	3.529843e-08
1.2198	1.495554	4.175658e-08
1.22547	1.495483	4.824477e-08
1.23117	1.495411	5.476313e-08
1.2369	1.49534	6.131182e-08
1.24265	1.495268	6.789097e-08
1.24843	1.495195	7.450072e-08
1.25424	1.495123	8.114121e-08
1.26007	1.49505	8.781259e-08
1.26593	1.494977	9.451501e-08
1.27182	1.494903	1.012486e-07
1.27774	1.49483	1.080135e-07
1.28368	1.494756	1.148099e-07
1.28965	1.494681	1.216379e-07
1.29565	1.494607	1.284976e-07
1.30167	1.494532	1.353893e-07
1.30773	1.494456	1.423130e-07
1.31381	1.494381	1.492689e-07
1.31992	1.494305	1.562571e-07
1.32606	1.494228	1.632779e-07
1.33223	1.494152	1.703313e-07
1.33843	1.494075	1.774176e-07
1.34465	1.493997	1.845368e-07
1.35091	1.493919	1.916891e-07
1.35719	1.493841	1.988746e-07
1.3635	1.493762	2.060936e-07
1.36985	1.493683	2.133462e-07
1.37622	1.493604	2.206325e-07
1.38262	1.493524	2.279527e-07
1.38905	1.493443	2.353070e-07
1.39551	1.493363	2.426954e-07
1.4	1.493306	2.478300e-07
1.402	1.493281	2.459890e-07
1.40852	1.4932	2.399893e-07
1.41507	1.493117	2.339616e-07
1.42166	1.493035	2.279059e-07
1.42827	1.492952	2.218221e-07
1.43491	1.492868	2.157100e-07
1.44159	1.492784	2.095694e-07
1.44829	1.492699	2.034002e-07
1.45503	1.492614	1.972024e-07
1.4618	1.492529	1.909758e-07
1.46859	1.492442	1.847201e-07
1.47543	1.492356	1.784354e-07
1.48229	1.492268	1.721215e-07
1.48918	1.492181	1.657781e-07
1.49611	1.492092	1.594053e-07
1.50307	1.492003	1.530029e-07
1.51006	1.491914	1.465706e-07
1.51708	1.491824	1.401084e-07
1.52414	1.491733	1.336162e-07
1.53123	1.491642	1.270938e-07
1.53835	1.49155	1.205410e-07
1.54551	1.491457	1.139578e-07
1.5527	1.491364	1.073439e-07
1.55992	1.49127	1.006993e-07
1.56717	1.491176	9.402380e-08
1.57446	1.49108	8.731722e-08
1.58179	1.490985	8.057945e-08
1.58914	1.490888	7.381034e-08
1.59654	1.490791	6.700974e-08
1.6	1.490745	6.382200e-08
1.60396	1.490693	6.426528e-08
1.61142	1.490594	6.510015e-08
1.61892	1.490495	6.593891e-08
1.62645	1.490395	6.678157e-08
1.63401	1.490294	6.762815e-08
1.64161	1.490193	6.847866e-08
1.64925	1.49009	6.933313e-08
1.65692	1.489987	7.019158e-08
1.66463	1.489883	7.105402e-08
1.67237	1.489779	7.192047e-08
1.68015	1.489673	7.279095e-08
1.68796	1.489567	7.366547e-08
1.69581	1.48946	7.454407e-08
1.7037	1.489352	7.542675e-08
1.71163	1.489243	7.631354e-08
1.71959	1.489133	7.720446e-08
1.72759	1.489023	7.809951e-08
1.73562	1.488911	7.899874e-08
1.74369	1.488799	7.990214e-08
1.75181	1.488686	8.080974e-08
1.75995	1.488572	8.172157e-08
1.76814	1.488457	8.263764e-08
1.77636	1.488341	8.355797e-08
1.78463	1.488224	8.448258e-08
1.79293	1.488106	8.541149e-08
1.8	1.488005	8.620300e-08
1.80127	1.487987	8.872680e-08
1.80964	1.487867	1.054233e-07
1.81806	1.487746	1.221975e-07
1.82652	1.487624	1.390498e-07
1.83501	1.487501	1.559804e-07
1.84355	1.487377	1.729897e-07
1.85212	1.487252	1.900782e-07
1.86074	1.487126	2.072462e-07
1.86939	1.486999	2.244940e-07
1.87809	1.486871	2.418220e-07
1.88682	1.486741	2.592307e-07
1.8956	1.486611	2.767203e-07
1.90442	1.486479	2.942912e-07
1.91328	1.486346	3.119439e-07
1.92218	1.486213	3.296787e-07
1.93112	1.486077	3.474960e-07
1.9401	1.485941	3.653962e-07
1.94912	1.485804	3.833796e-07
1.95819	1.485665	4.014466e-07
1.9673	1.485525	4.195977e-07
1.97645	1.485383	4.378333e-07
1.98564	1.485241	4.561536e-07
1.99488	1.485097	4.745592e-07
2	1.485017	4.847700e-07
2.00416	1.484952	5.245159e-07
2.01348	1.484806	6.136868e-07
2.02284	1.484658	7.032724e-07
2.03225	1.484509	7.932747e-07
2.0417	1.484358	8.836957e-07
2.0512	1.484206	9.745372e-07
2.06074	1.484053	1.065801e-06
2.07033	1.483898	1.157490e-06
2.07996	1.483742	1.249605e-06
2.08963	1.483585	1.342148e-06
2.09935	1.483425	1.435122e-06
2.10912	1.483265	1.528529e-06
2.11893	1.483103	1.622370e-06
2.12878	1.482939	1.716647e-06
2.13868	1.482774	1.811363e-06
2.14863	1.482607	1.906519e-06
2.15862	1.482439	2.002118e-06
2.16867	1.482269	2.098162e-06
2.17875	1.482098	2.194652e-06
2.18889	1.481925	2.291592e-06
2.19907	1.48175	2.388982e-06
2.2	1.481734	2.397900e-06
2.2093	1.481573	2.530070e-06
2.21957	1.481395	2.676171e-06
2.2299	1.481215	2.822952e-06
2.24027	1.481033	2.970416e-06
2.25069	1.48085	3.118565e-06
2.26116	1.480665	3.267404e-06
2.27167	1.480478	3.416935e-06
2.28224	1.480289	3.567161e-06
2.29286	1.480098	3.718087e-06
2.30352	1.479905	3.869714e-06
2.31424	1.479711	4.022046e-06
2.325	1.479514	4.175088e-06

Optical transmission calculator

Free-standing sample in vacuum, normal incidence

Transmittance T: —
Reflectance R: —

Fresnel reflection calculator

R_p: —
R_s: —
R = (R_p+R_s)/2: —
Phase φ_p: —
Phase φ_s: —
Brewster angle θ_B: —
Critical angle θ_C: —

K4A (CDGM): all datasets

K (Crown)

K4A n,k 0.365–2.325 µm default

About K4A (CDGM)

CDGM Glass Co., Ltd. is a leading manufacturer of optical glass based in China. The company offers a wide range of optical materials, including various types of crown and flint glasses, which are used in applications ranging from consumer electronics to advanced scientific instruments. Known for their capacity for large-scale production as well as their commitment to quality, CDGM has positioned itself as a major player in both domestic and international markets. Their optical glass products are often used in lenses, prisms, and other optical components that require high precision and reliability. With an extensive catalog that caters to different optical requirements, such as high refractive indices or low dispersion, CDGM serves a diverse clientele including manufacturers of microscopes, telescopes, cameras, and other high-precision optical equipment. The company's expertise in glass science and its ability to provide customized solutions have made it a go-to supplier for businesses seeking high-quality, reliable optical glass.

More about K4A (CDGM) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/specs/cdgm/optical/K4A.yml
ID: ds_d06254bb1aa0
API: /v1/datasets/ds_d06254bb1aa0

Plot