Optical constants

Refractive index of (C₃H₄O₂)_n (Polylactic acid, PLA)

Bodurov et al. 2016: PDLA; n 0.405–0.635 µm

Data: formula 1
Range: 0.405–0.635 µm
Temperature: 297 K
Licence: CC0-1.0

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 1.45886
Extinction coefficient k: 0

Permittivity ε₁: 2.12828
Permittivity ε₂: 0

Absorption coefficient α: 0 cm⁻¹
Penetration depth δ = λ/(2πk): — nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: -0.197763 µm⁻¹

Group index n_g: 1.57507
Group velocity dispersion: 425.793 fs²/mm

Dispersion parameter D: -2322.93 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

# (C3H4O2)n (Polylactic acid, PLA): Bodurov et al. 2016: PDLA; n 0.405–0.635 µm
polylactic_acid = ls.fetch_refractiveindex("organic", "polylactic_acid", "Bodurov", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(polylactic_acid.range_nm)  # (405, 635) nm
eps = polylactic_acid.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_f5fb7a57ffb7/lightsmith"
polylactic_acid = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(polylactic_acid.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (polylactic-acid/bodurov-2016).

# ... load polylactic_acid as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=polylactic_acid)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=405, stop_nm=635, 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"]).

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_f5fb7a57ffb7/lightsmith?model=drude_lorentz"
polylactic_acid_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))

A dispersive Drude–Lorentz model for time-domain solvers.

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 (formula 1), λ in µm

n^{2} - 1 = \frac{0.9809 λ^{2}}{λ^{2} - {0.2123719}^{2}}

Valid from 0.405 to 0.635 µm.

Coefficients as stored

C_i	Value
C1	0.0
C2	0.9809
C3	0.2123719

Comments and conditions

PDLA. 45-μm film on glass substrate. 24 °C.

Conditions

temperature: 297 K
film thickness: 45e-6
substrate: glass

References

I. Bodurov, I. Vlaeva, A. Viraneva, T. Yovcheva, S. Sainov. Modified design of a laser refractometer. Nanosci. Nanotechnol. 16, 31-33 (2016)

Cite

I. Bodurov, I. Vlaeva, A. Viraneva, T. Yovcheva, S. Sainov. Modified design of a laser refractometer. Nanosci. Nanotechnol. 16, 31-33 (2016); Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

Computed on 400 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

(C3H4O2)n (Polylactic acid, PLA), Bodurov et al. 2016: PDLA; n 0.405–0.635 µm: n and k versus wavelength
λ (µm)	n
0.405	1.533919
0.405457	1.533543
0.405914	1.533168
0.406372	1.532794
0.40683	1.532422
0.407289	1.532051
0.407748	1.531682
0.408208	1.531314
0.408669	1.530947
0.409129	1.530582
0.409591	1.530218
0.410053	1.529855
0.410515	1.529494
0.410978	1.529134
0.411442	1.528775
0.411906	1.528418
0.41237	1.528062
0.412835	1.527707
0.413301	1.527353
0.413767	1.527001
0.414234	1.52665
0.414701	1.5263
0.415169	1.525952
0.415637	1.525605
0.416106	1.525259
0.416575	1.524914
0.417045	1.524571
0.417515	1.524229
0.417986	1.523888
0.418457	1.523548
0.418929	1.523209
0.419402	1.522872
0.419875	1.522536
0.420348	1.522201
0.420822	1.521868
0.421297	1.521535
0.421772	1.521204
0.422248	1.520874
0.422724	1.520545
0.423201	1.520217
0.423678	1.51989
0.424156	1.519565
0.424634	1.519241
0.425113	1.518917
0.425592	1.518595
0.426072	1.518275
0.426553	1.517955
0.427034	1.517636
0.427516	1.517319
0.427998	1.517002
0.42848	1.516687
0.428964	1.516373
0.429448	1.51606
0.429932	1.515748
0.430417	1.515437
0.430902	1.515127
0.431388	1.514819
0.431875	1.514511
0.432362	1.514204
0.432849	1.513899
0.433337	1.513594
0.433826	1.513291
0.434315	1.512989
0.434805	1.512687
0.435296	1.512387
0.435787	1.512088
0.436278	1.51179
0.43677	1.511493
0.437263	1.511197
0.437756	1.510902
0.43825	1.510608
0.438744	1.510314
0.439239	1.510022
0.439734	1.509731
0.44023	1.509441
0.440726	1.509152
0.441223	1.508864
0.441721	1.508577
0.442219	1.508291
0.442718	1.508006
0.443217	1.507722
0.443717	1.507439
0.444218	1.507156
0.444719	1.506875
0.44522	1.506595
0.445722	1.506315
0.446225	1.506037
0.446728	1.50576
0.447232	1.505483
0.447736	1.505207
0.448241	1.504933
0.448747	1.504659
0.449253	1.504386
0.44976	1.504114
0.450267	1.503843
0.450775	1.503573
0.451283	1.503304
0.451792	1.503036
0.452302	1.502768
0.452812	1.502502
0.453322	1.502236
0.453834	1.501972
0.454345	1.501708
0.454858	1.501445
0.455371	1.501183
0.455884	1.500922
0.456398	1.500661
0.456913	1.500402
0.457429	1.500143
0.457944	1.499886
0.458461	1.499629
0.458978	1.499373
0.459496	1.499117
0.460014	1.498863
0.460533	1.49861
0.461052	1.498357
0.461572	1.498105
0.462093	1.497854
0.462614	1.497604
0.463135	1.497355
0.463658	1.497106
0.464181	1.496858
0.464704	1.496611
0.465228	1.496365
0.465753	1.49612
0.466278	1.495876
0.466804	1.495632
0.467331	1.495389
0.467858	1.495147
0.468385	1.494905
0.468913	1.494665
0.469442	1.494425
0.469972	1.494186
0.470502	1.493948
0.471032	1.493711
0.471564	1.493474
0.472095	1.493238
0.472628	1.493003
0.473161	1.492769
0.473695	1.492535
0.474229	1.492302
0.474764	1.49207
0.475299	1.491839
0.475835	1.491608
0.476372	1.491378
0.476909	1.491149
0.477447	1.490921
0.477985	1.490693
0.478524	1.490466
0.479064	1.49024
0.479604	1.490014
0.480145	1.48979
0.480687	1.489565
0.481229	1.489342
0.481772	1.48912
0.482315	1.488898
0.482859	1.488676
0.483403	1.488456
0.483949	1.488236
0.484494	1.488017
0.485041	1.487799
0.485588	1.487581
0.486136	1.487364
0.486684	1.487148
0.487233	1.486932
0.487782	1.486717
0.488332	1.486503
0.488883	1.486289
0.489434	1.486076
0.489986	1.485864
0.490539	1.485652
0.491092	1.485441
0.491646	1.485231
0.492201	1.485021
0.492756	1.484813
0.493311	1.484604
0.493868	1.484397
0.494425	1.48419
0.494982	1.483983
0.495541	1.483778
0.496099	1.483572
0.496659	1.483368
0.497219	1.483164
0.49778	1.482961
0.498341	1.482759
0.498903	1.482557
0.499466	1.482356
0.500029	1.482155
0.500593	1.481955
0.501158	1.481756
0.501723	1.481557
0.502289	1.481359
0.502855	1.481161
0.503422	1.480964
0.50399	1.480768
0.504559	1.480572
0.505128	1.480377
0.505697	1.480183
0.506268	1.479989
0.506839	1.479795
0.50741	1.479603
0.507982	1.479411
0.508555	1.479219
0.509129	1.479028
0.509703	1.478838
0.510278	1.478648
0.510853	1.478459
0.51143	1.47827
0.512006	1.478082
0.512584	1.477895
0.513162	1.477708
0.513741	1.477522
0.51432	1.477336
0.5149	1.477151
0.515481	1.476966
0.516062	1.476782
0.516644	1.476599
0.517227	1.476416
0.51781	1.476233
0.518394	1.476051
0.518979	1.47587
0.519564	1.47569
0.52015	1.475509
0.520737	1.47533
0.521324	1.475151
0.521912	1.474972
0.5225	1.474794
0.52309	1.474617
0.52368	1.47444
0.52427	1.474263
0.524862	1.474088
0.525453	1.473912
0.526046	1.473737
0.526639	1.473563
0.527233	1.473389
0.527828	1.473216
0.528423	1.473043
0.529019	1.472871
0.529616	1.4727
0.530213	1.472528
0.530811	1.472358
0.53141	1.472188
0.532009	1.472018
0.532609	1.471849
0.53321	1.47168
0.533811	1.471512
0.534413	1.471345
0.535016	1.471178
0.535619	1.471011
0.536223	1.470845
0.536828	1.470679
0.537433	1.470514
0.53804	1.470349
0.538646	1.470185
0.539254	1.470022
0.539862	1.469859
0.540471	1.469696
0.54108	1.469534
0.541691	1.469372
0.542302	1.469211
0.542913	1.46905
0.543525	1.46889
0.544138	1.46873
0.544752	1.46857
0.545366	1.468412
0.545982	1.468253
0.546597	1.468095
0.547214	1.467938
0.547831	1.467781
0.548449	1.467624
0.549067	1.467468
0.549687	1.467312
0.550306	1.467157
0.550927	1.467003
0.551548	1.466848
0.55217	1.466694
0.552793	1.466541
0.553417	1.466388
0.554041	1.466236
0.554666	1.466084
0.555291	1.465932
0.555917	1.465781
0.556544	1.46563
0.557172	1.46548
0.5578	1.46533
0.55843	1.465181
0.559059	1.465032
0.55969	1.464883
0.560321	1.464735
0.560953	1.464588
0.561586	1.46444
0.562219	1.464294
0.562853	1.464147
0.563488	1.464001
0.564123	1.463856
0.56476	1.463711
0.565396	1.463566
0.566034	1.463422
0.566673	1.463278
0.567312	1.463134
0.567951	1.462991
0.568592	1.462849
0.569233	1.462707
0.569875	1.462565
0.570518	1.462423
0.571161	1.462282
0.571805	1.462142
0.57245	1.462002
0.573096	1.461862
0.573742	1.461723
0.574389	1.461584
0.575037	1.461445
0.575686	1.461307
0.576335	1.461169
0.576985	1.461032
0.577636	1.460895
0.578287	1.460758
0.578939	1.460622
0.579592	1.460486
0.580246	1.460351
0.5809	1.460216
0.581555	1.460081
0.582211	1.459947
0.582868	1.459813
0.583525	1.45968
0.584183	1.459546
0.584842	1.459414
0.585502	1.459281
0.586162	1.459149
0.586823	1.459018
0.587485	1.458887
0.588148	1.458756
0.588811	1.458625
0.589475	1.458495
0.59014	1.458365
0.590805	1.458236
0.591472	1.458107
0.592139	1.457978
0.592807	1.45785
0.593475	1.457722
0.594144	1.457594
0.594814	1.457467
0.595485	1.45734
0.596157	1.457214
0.596829	1.457088
0.597502	1.456962
0.598176	1.456837
0.598851	1.456712
0.599526	1.456587
0.600202	1.456462
0.600879	1.456338
0.601557	1.456215
0.602235	1.456091
0.602915	1.455968
0.603595	1.455846
0.604275	1.455724
0.604957	1.455602
0.605639	1.45548
0.606322	1.455359
0.607006	1.455238
0.60769	1.455117
0.608376	1.454997
0.609062	1.454877
0.609749	1.454757
0.610437	1.454638
0.611125	1.454519
0.611814	1.454401
0.612504	1.454282
0.613195	1.454165
0.613887	1.454047
0.614579	1.45393
0.615272	1.453813
0.615966	1.453696
0.616661	1.45358
0.617356	1.453464
0.618052	1.453348
0.618749	1.453233
0.619447	1.453118
0.620146	1.453003
0.620845	1.452889
0.621545	1.452775
0.622246	1.452661
0.622948	1.452548
0.623651	1.452435
0.624354	1.452322
0.625058	1.452209
0.625763	1.452097
0.626469	1.451985
0.627175	1.451874
0.627883	1.451762
0.628591	1.451652
0.6293	1.451541
0.630009	1.451431
0.63072	1.451321
0.631431	1.451211
0.632143	1.451101
0.632856	1.450992
0.63357	1.450883
0.634285	1.450775
0.635	1.450667

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: —

(C₃H₄O₂)_n (Polylactic acid, PLA): all datasets

Bodurov et al. 2016: PDLA; n 0.405–0.635 µm n 0.405–0.635 µm default

About (C3H4O2)n (Polylactic acid, PLA)

Polylactic acid (PLA, (C₃H₄O₂)_n) is a biodegradable and bioactive thermoplastic derived from renewable resources like corn starch or sugarcane. It has captured significant attention due to its compostability under industrial conditions, positioning it as an eco-friendly alternative to petroleum-based plastics. PLA is utilized in a multitude of applications ranging from food packaging to biomedicine, such as drug delivery systems and surgical implants. In the realm of optics, PLA is typically transparent, with a refractive index that can be influenced by factors like crystallinity and processing methods. Though its mechanical strength is comparable to that of polystyrene, PLA has a lower melting temperature, which can limit its use in certain high-temperature applications. Nevertheless, due to its biocompatibility and environmentally friendly nature, polylactic acid continues to be a material of interest for both research and commercial purposes.

Polylactic acid - Wikipedia

More about (C3H4O2)n (Polylactic acid, PLA) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/organic/(C3H4O2)n - polylactic acid/nk/Bodurov.yml
ID: ds_f5fb7a57ffb7
API: /v1/datasets/ds_f5fb7a57ffb7

Plot