Optical constants

Refractive index of BAF4 (CDGM)

BAF4: n,k 0.365–0.7065 µm

Data: formula 3 + tabulated k
Range: 0.365–0.7065 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: 1.58271
Extinction coefficient k: 1.51379e-08

Permittivity ε₁: 2.50497
Permittivity ε₂: 4.79177e-08

Absorption coefficient α: 0.00323737 cm⁻¹
Penetration depth δ = λ/(2πk): 6.17785e+09 nm

Abbe number V_d: 46.506
Chromatic dispersion dn/dλ: -0.0640223 µm⁻¹

Group index n_g: 1.62033
Group velocity dispersion: 118.975 fs²/mm

Dispersion parameter D: -649.071 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

# BAF4 (CDGM): BAF4
cdgm_baf4 = ls.fetch_refractiveindex("specs", "CDGM-optical", "BAF4", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(cdgm_baf4.range_nm)  # (365, 706.5) nm
eps = cdgm_baf4.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_67810556d1f8/lightsmith"
cdgm_baf4 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(cdgm_baf4.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (cdgm-baf4/cdgm).

# ... load cdgm_baf4 as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=cdgm_baf4)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=706, 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

Polynomial (formula 3), λ in µm

n^{2} = 2.451472 - 0.0065118879 λ^{2.0} + 0.019377342 λ^{- 2.0} - 0.00030637647 λ^{- 4.0} + 0.00010174985 λ^{- 6.0} - 3.9270356 \times 10^{-6} λ^{- 8.0}

Valid from 0.365 to 0.7065 µm.

Coefficients as stored

C_i	Value
C1	2.451472
C2	-0.0065118879
C3	2.0
C4	0.019377342
C5	-2.0
C6	-0.00030637647
C7	-4.0
C8	0.00010174985
C9	-6.0
C10	-3.9270356e-06
C11	-8.0

Comments and conditions

Conditions

temperature: 293 K

Properties

nd: 1.582712
Vd: 46.505886
glass code: 583465
glass status: preferred
density: value: 3280
thermal expansion: value: 7.8e-06, temperature range: 243 343; value: 9.1e-06, temperature range: 293 573
dPgF: 0.0007

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 413 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

BAF4 (CDGM), BAF4: n and k versus wavelength
λ (µm)	n	k
0.365	1.61535	1.152895e-07
0.365605	1.615155	1.118260e-07
0.36621	1.61496	1.083568e-07
0.366817	1.614767	1.048818e-07
0.367425	1.614574	1.014011e-07
0.368033	1.614382	9.791457e-08
0.368643	1.614191	9.442230e-08
0.369254	1.614001	9.092424e-08
0.369865	1.613812	8.742039e-08
0.37	1.61377	8.664900e-08
0.370478	1.613623	8.601851e-08
0.371092	1.613436	8.520907e-08
0.371707	1.613249	8.439829e-08
0.372322	1.613063	8.358616e-08
0.372939	1.612878	8.277269e-08
0.373557	1.612693	8.195788e-08
0.374176	1.61251	8.114171e-08
0.374796	1.612327	8.032419e-08
0.375416	1.612145	7.950532e-08
0.376038	1.611964	7.868509e-08
0.376661	1.611784	7.786350e-08
0.377285	1.611604	7.704055e-08
0.37791	1.611425	7.621623e-08
0.378536	1.611248	7.539055e-08
0.379163	1.61107	7.456351e-08
0.379791	1.610894	7.373509e-08
0.38	1.610836	7.346000e-08
0.380421	1.610718	7.247577e-08
0.381051	1.610544	7.100099e-08
0.381682	1.61037	6.952376e-08
0.382314	1.610196	6.804409e-08
0.382948	1.610024	6.656197e-08
0.383582	1.609852	6.507739e-08
0.384217	1.609681	6.359035e-08
0.384854	1.609511	6.210085e-08
0.385491	1.609341	6.060888e-08
0.38613	1.609173	5.911445e-08
0.38677	1.609005	5.761753e-08
0.38741	1.608837	5.611813e-08
0.388052	1.608671	5.461626e-08
0.388695	1.608505	5.311189e-08
0.389339	1.60834	5.160503e-08
0.389984	1.608176	5.009567e-08
0.39	1.608172	5.005800e-08
0.39063	1.608012	4.912254e-08
0.391277	1.607849	4.816159e-08
0.391925	1.607687	4.719904e-08
0.392574	1.607526	4.623490e-08
0.393225	1.607365	4.526916e-08
0.393876	1.607205	4.430183e-08
0.394529	1.607045	4.333289e-08
0.395182	1.606887	4.236234e-08
0.395837	1.606729	4.139019e-08
0.396493	1.606571	4.041643e-08
0.397149	1.606415	3.944105e-08
0.397807	1.606259	3.846406e-08
0.398466	1.606104	3.748545e-08
0.399126	1.605949	3.650521e-08
0.399788	1.605795	3.552336e-08
0.4	1.605746	3.520800e-08
0.40045	1.605642	3.509570e-08
0.401113	1.605489	3.493012e-08
0.401778	1.605337	3.476427e-08
0.402443	1.605186	3.459814e-08
0.40311	1.605036	3.443174e-08
0.403778	1.604886	3.426506e-08
0.404447	1.604736	3.409811e-08
0.405117	1.604588	3.393088e-08
0.405788	1.60444	3.376337e-08
0.40646	1.604292	3.359558e-08
0.407133	1.604146	3.342752e-08
0.407808	1.603999	3.325918e-08
0.408483	1.603854	3.309056e-08
0.40916	1.603709	3.292166e-08
0.409838	1.603565	3.275248e-08
0.410517	1.603421	3.258302e-08
0.411197	1.603278	3.241328e-08
0.411878	1.603136	3.224326e-08
0.41256	1.602994	3.207295e-08
0.413244	1.602853	3.190237e-08
0.413928	1.602713	3.173150e-08
0.414614	1.602573	3.156035e-08
0.415301	1.602433	3.138891e-08
0.415989	1.602294	3.121719e-08
0.416678	1.602156	3.104519e-08
0.417368	1.602019	3.087290e-08
0.41806	1.601882	3.070033e-08
0.418752	1.601745	3.052747e-08
0.419446	1.60161	3.035432e-08
0.42	1.601502	3.021600e-08
0.420141	1.601474	3.020129e-08
0.420837	1.60134	3.012849e-08
0.421534	1.601206	3.005556e-08
0.422232	1.601072	2.998252e-08
0.422932	1.600939	2.990936e-08
0.423632	1.600807	2.983607e-08
0.424334	1.600675	2.976267e-08
0.425037	1.600543	2.968914e-08
0.425741	1.600413	2.961549e-08
0.426446	1.600283	2.954172e-08
0.427153	1.600153	2.946783e-08
0.42786	1.600024	2.939381e-08
0.428569	1.599895	2.931967e-08
0.429279	1.599767	2.924541e-08
0.42999	1.59964	2.917103e-08
0.430703	1.599513	2.909652e-08
0.431416	1.599386	2.902189e-08
0.432131	1.599261	2.894713e-08
0.432847	1.599135	2.887225e-08
0.433564	1.59901	2.879725e-08
0.434282	1.598886	2.872212e-08
0.435001	1.598762	2.864687e-08
0.435722	1.598639	2.857150e-08
0.436444	1.598516	2.849600e-08
0.437167	1.598394	2.842037e-08
0.437891	1.598272	2.834462e-08
0.438616	1.598151	2.826874e-08
0.439343	1.59803	2.819274e-08
0.44	1.597922	2.812400e-08
0.440071	1.59791	2.811549e-08
0.4408	1.59779	2.802764e-08
0.44153	1.597671	2.793965e-08
0.442261	1.597552	2.785151e-08
0.442994	1.597434	2.776323e-08
0.443728	1.597316	2.767480e-08
0.444463	1.597199	2.758623e-08
0.445199	1.597082	2.749750e-08
0.445937	1.596966	2.740864e-08
0.446675	1.59685	2.731962e-08
0.447415	1.596734	2.723045e-08
0.448156	1.59662	2.714114e-08
0.448899	1.596505	2.705168e-08
0.449643	1.596391	2.696208e-08
0.450387	1.596278	2.687232e-08
0.451133	1.596165	2.678241e-08
0.451881	1.596052	2.669236e-08
0.452629	1.59594	2.660216e-08
0.453379	1.595828	2.651180e-08
0.45413	1.595717	2.642130e-08
0.454883	1.595606	2.633065e-08
0.455636	1.595496	2.623985e-08
0.456391	1.595386	2.614889e-08
0.457147	1.595277	2.605779e-08
0.457904	1.595168	2.596654e-08
0.458663	1.595059	2.587513e-08
0.459423	1.594951	2.578357e-08
0.46	1.594869	2.571400e-08
0.460184	1.594843	2.568895e-08
0.460946	1.594736	2.558501e-08
0.46171	1.594629	2.548090e-08
0.462474	1.594523	2.537661e-08
0.463241	1.594417	2.527215e-08
0.464008	1.594311	2.516751e-08
0.464777	1.594206	2.506271e-08
0.465547	1.594101	2.495772e-08
0.466318	1.593997	2.485257e-08
0.46709	1.593893	2.474724e-08
0.467864	1.59379	2.464174e-08
0.468639	1.593687	2.453606e-08
0.469415	1.593584	2.443021e-08
0.470193	1.593482	2.432418e-08
0.470972	1.59338	2.421797e-08
0.471752	1.593279	2.411159e-08
0.472534	1.593178	2.400504e-08
0.473316	1.593077	2.389830e-08
0.474101	1.592977	2.379139e-08
0.474886	1.592877	2.368431e-08
0.475673	1.592777	2.357704e-08
0.476461	1.592678	2.346960e-08
0.47725	1.59258	2.336198e-08
0.47804	1.592481	2.325418e-08
0.478832	1.592384	2.314621e-08
0.479626	1.592286	2.303805e-08
0.48	1.59224	2.298700e-08
0.48042	1.592189	2.292308e-08
0.481216	1.592092	2.280199e-08
0.482013	1.591996	2.268070e-08
0.482812	1.5919	2.255921e-08
0.483611	1.591804	2.243752e-08
0.484413	1.591709	2.231562e-08
0.485215	1.591614	2.219353e-08
0.486019	1.59152	2.207123e-08
0.486824	1.591425	2.194873e-08
0.48763	1.591332	2.182603e-08
0.488438	1.591238	2.170312e-08
0.489247	1.591145	2.158001e-08
0.490058	1.591052	2.145670e-08
0.49087	1.59096	2.133318e-08
0.491683	1.590868	2.120946e-08
0.492497	1.590776	2.108553e-08
0.493313	1.590685	2.096140e-08
0.49413	1.590594	2.083706e-08
0.494949	1.590504	2.071252e-08
0.495769	1.590413	2.058777e-08
0.49659	1.590323	2.046281e-08
0.497413	1.590234	2.033764e-08
0.498237	1.590145	2.021227e-08
0.499062	1.590056	2.008669e-08
0.499889	1.589967	1.996091e-08
0.5	1.589955	1.994400e-08
0.500717	1.589879	1.990956e-08
0.501546	1.589791	1.986971e-08
0.502377	1.589704	1.982979e-08
0.50321	1.589616	1.978981e-08
0.504043	1.58953	1.974977e-08
0.504878	1.589443	1.970965e-08
0.505714	1.589357	1.966948e-08
0.506552	1.589271	1.962923e-08
0.507391	1.589185	1.958892e-08
0.508232	1.5891	1.954854e-08
0.509074	1.589015	1.950809e-08
0.509917	1.58893	1.946758e-08
0.510762	1.588846	1.942700e-08
0.511608	1.588762	1.938635e-08
0.512456	1.588678	1.934564e-08
0.513304	1.588595	1.930486e-08
0.514155	1.588512	1.926401e-08
0.515006	1.588429	1.922309e-08
0.51586	1.588347	1.918210e-08
0.516714	1.588265	1.914105e-08
0.51757	1.588183	1.909993e-08
0.518428	1.588101	1.905874e-08
0.519286	1.58802	1.901748e-08
0.520147	1.587939	1.897616e-08
0.521008	1.587859	1.893476e-08
0.521871	1.587778	1.889330e-08
0.522736	1.587698	1.885177e-08
0.523602	1.587618	1.881017e-08
0.524469	1.587539	1.876850e-08
0.525338	1.58746	1.872676e-08
0.526208	1.587381	1.868495e-08
0.52708	1.587302	1.864308e-08
0.527953	1.587224	1.860113e-08
0.528828	1.587146	1.855912e-08
0.529704	1.587068	1.851703e-08
0.530581	1.586991	1.847488e-08
0.53146	1.586914	1.843265e-08
0.532341	1.586837	1.839036e-08
0.533222	1.58676	1.834799e-08
0.534106	1.586684	1.830556e-08
0.534991	1.586608	1.826305e-08
0.535877	1.586532	1.822048e-08
0.536765	1.586457	1.817783e-08
0.537654	1.586381	1.813511e-08
0.538544	1.586306	1.809233e-08
0.539437	1.586232	1.804947e-08
0.54033	1.586157	1.800654e-08
0.541225	1.586083	1.796354e-08
0.542122	1.586009	1.792047e-08
0.54302	1.585936	1.787732e-08
0.543919	1.585862	1.783411e-08
0.544821	1.585789	1.779082e-08
0.545723	1.585716	1.774747e-08
0.546627	1.585644	1.770404e-08
0.547533	1.585572	1.766053e-08
0.54844	1.585499	1.761696e-08
0.549348	1.585428	1.757331e-08
0.55	1.585376	1.754200e-08
0.550258	1.585356	1.752549e-08
0.55117	1.585285	1.746721e-08
0.552083	1.585214	1.740883e-08
0.552997	1.585143	1.735035e-08
0.553913	1.585072	1.729178e-08
0.554831	1.585002	1.723310e-08
0.55575	1.584932	1.717434e-08
0.556671	1.584862	1.711547e-08
0.557593	1.584793	1.705651e-08
0.558517	1.584723	1.699745e-08
0.559442	1.584654	1.693829e-08
0.560369	1.584585	1.687903e-08
0.561297	1.584517	1.681967e-08
0.562227	1.584449	1.676022e-08
0.563158	1.58438	1.670067e-08
0.564091	1.584313	1.664102e-08
0.565025	1.584245	1.658127e-08
0.565961	1.584177	1.652142e-08
0.566899	1.58411	1.646147e-08
0.567838	1.584043	1.640143e-08
0.568779	1.583977	1.634128e-08
0.569721	1.58391	1.628104e-08
0.570665	1.583844	1.622069e-08
0.57161	1.583778	1.616024e-08
0.572557	1.583712	1.609970e-08
0.573506	1.583646	1.603905e-08
0.574456	1.583581	1.597831e-08
0.575407	1.583516	1.591746e-08
0.57636	1.583451	1.585651e-08
0.577315	1.583386	1.579546e-08
0.578272	1.583322	1.573431e-08
0.57923	1.583258	1.567306e-08
0.580189	1.583194	1.561171e-08
0.58115	1.58313	1.555025e-08
0.582113	1.583066	1.548870e-08
0.583077	1.583003	1.542704e-08
0.584043	1.58294	1.536528e-08
0.585011	1.582877	1.530342e-08
0.58598	1.582814	1.524145e-08
0.586951	1.582752	1.517938e-08
0.587923	1.582689	1.511721e-08
0.588897	1.582627	1.505494e-08
0.589872	1.582565	1.499256e-08
0.590849	1.582504	1.493008e-08
0.591828	1.582442	1.486750e-08
0.592809	1.582381	1.480481e-08
0.593791	1.58232	1.474202e-08
0.594774	1.582259	1.467913e-08
0.59576	1.582198	1.461613e-08
0.596747	1.582138	1.455302e-08
0.597735	1.582078	1.448982e-08
0.598725	1.582018	1.442650e-08
0.599717	1.581958	1.436308e-08
0.6	1.581941	1.434500e-08
0.600711	1.581898	1.436200e-08
0.601706	1.581839	1.438580e-08
0.602703	1.581779	1.440964e-08
0.603701	1.58172	1.443353e-08
0.604701	1.581662	1.445745e-08
0.605703	1.581603	1.448141e-08
0.606706	1.581544	1.450541e-08
0.607711	1.581486	1.452945e-08
0.608718	1.581428	1.455353e-08
0.609726	1.58137	1.457765e-08
0.610736	1.581312	1.460181e-08
0.611748	1.581255	1.462601e-08
0.612761	1.581198	1.465025e-08
0.613777	1.58114	1.467454e-08
0.614793	1.581083	1.469886e-08
0.615812	1.581027	1.472322e-08
0.616832	1.58097	1.474762e-08
0.617854	1.580914	1.477206e-08
0.618877	1.580857	1.479654e-08
0.619902	1.580801	1.482107e-08
0.620929	1.580746	1.484563e-08
0.621958	1.58069	1.487024e-08
0.622988	1.580634	1.489488e-08
0.62402	1.580579	1.491957e-08
0.625054	1.580524	1.494429e-08
0.62609	1.580469	1.496906e-08
0.627127	1.580414	1.499387e-08
0.628166	1.58036	1.501872e-08
0.629206	1.580305	1.504361e-08
0.630249	1.580251	1.506854e-08
0.631293	1.580197	1.509352e-08
0.632338	1.580143	1.511853e-08
0.633386	1.580089	1.514359e-08
0.634435	1.580035	1.516869e-08
0.635486	1.579982	1.519383e-08
0.636539	1.579929	1.521901e-08
0.637593	1.579876	1.524423e-08
0.63865	1.579823	1.526950e-08
0.639708	1.57977	1.529480e-08
0.640767	1.579718	1.532015e-08
0.641829	1.579665	1.534554e-08
0.642892	1.579613	1.537098e-08
0.643957	1.579561	1.539645e-08
0.645024	1.579509	1.542197e-08
0.646092	1.579457	1.544753e-08
0.647163	1.579406	1.547313e-08
0.648235	1.579354	1.549877e-08
0.649308	1.579303	1.552446e-08
0.65	1.57927	1.554100e-08
0.650384	1.579252	1.555018e-08
0.651461	1.579201	1.557593e-08
0.652541	1.57915	1.560172e-08
0.653622	1.579099	1.562756e-08
0.654704	1.579049	1.565344e-08
0.655789	1.578999	1.567936e-08
0.656875	1.578949	1.570532e-08
0.657964	1.578899	1.573133e-08
0.659053	1.578849	1.575738e-08
0.660145	1.578799	1.578347e-08
0.661239	1.578749	1.580961e-08
0.662334	1.5787	1.583579e-08
0.663431	1.578651	1.586201e-08
0.66453	1.578602	1.588828e-08
0.665631	1.578553	1.591459e-08
0.666734	1.578504	1.594094e-08
0.667838	1.578455	1.596734e-08
0.668945	1.578407	1.599378e-08
0.670053	1.578358	1.602027e-08
0.671163	1.57831	1.604679e-08
0.672275	1.578262	1.607337e-08
0.673388	1.578214	1.609998e-08
0.674504	1.578167	1.612664e-08
0.675621	1.578119	1.615335e-08
0.676741	1.578071	1.618010e-08
0.677862	1.578024	1.620689e-08
0.678985	1.577977	1.623373e-08
0.680109	1.57793	1.626061e-08
0.681236	1.577883	1.628754e-08
0.682364	1.577836	1.631451e-08
0.683495	1.57779	1.634153e-08
0.684627	1.577743	1.636859e-08
0.685761	1.577697	1.639569e-08
0.686897	1.577651	1.642284e-08
0.688035	1.577605	1.645004e-08
0.689175	1.577559	1.647728e-08
0.690317	1.577513	1.650457e-08
0.69146	1.577467	1.653190e-08
0.692606	1.577422	1.655927e-08
0.693753	1.577376	1.658670e-08
0.694902	1.577331	1.661416e-08
0.696053	1.577286	1.664168e-08
0.697206	1.577241	1.666923e-08
0.698361	1.577196	1.669684e-08
0.699518	1.577151	1.672449e-08
0.7	1.577133	1.673600e-08
0.700677	1.577107	1.670898e-08
0.701838	1.577062	1.666265e-08
0.703	1.577018	1.661625e-08
0.704165	1.576974	1.656977e-08
0.705332	1.57693	1.652322e-08
0.7065	1.576886	1.647658e-08

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: —

BAF4 (CDGM): all datasets

BAF (Barium flint)

BAF4 n,k 0.365–0.7065 µm default

About BAF4 (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 BAF4 (CDGM) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/specs/cdgm/optical/BAF4.yml
ID: ds_67810556d1f8
API: /v1/datasets/ds_67810556d1f8

Plot