Optical constants
Refractive index of LAK09 (HIKARI)
LAK09: n 0.4–0.7 µm
- Data
- formula 3 + tabulated k
- Range
- 0.4–0.7 µm
- Temperature
- 293 K
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 1.734
- Extinction coefficient k
- 0
- Permittivity ε1
- 3.00675
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- 51.483
- Chromatic dispersion dn/dλ
- -0.0734253 µm⁻¹
- Group index ng
- 1.77714
- Group velocity dispersion
- 130.881 fs²/mm
- Dispersion parameter D
- -714.025 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
# LAK09 (HIKARI): LAK09
hikari_lak09 = ls.fetch_refractiveindex("specs", "HIKARI-optical", "LAK09", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(hikari_lak09.range_nm) # (400, 700) nm
eps = hikari_lak09.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_30f82a266194/lightsmith"
hikari_lak09 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(hikari_lak09.source) # citation and provenance travel with the data
Any dataset here, as the library's Tabulated material (hikari-lak09/hikari).
# ... load hikari_lak09 as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=hikari_lak09)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=700, 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"]).
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 µmValid from 0.4 to 0.7 µm.
Coefficients as stored
| Ci | Value |
|---|---|
| C1 | 2.953102 |
| C2 | -0.01967247 |
| C3 | 2.0 |
| C4 | 0.01742579 |
| C5 | -2.0 |
| C6 | 0.001528665 |
| C7 | -4.0 |
| C8 | -0.0001370287 |
| C9 | -6.0 |
| C10 | 6.723533e-06 |
| C11 | -8.0 |
Comments and conditions
Conditions
- temperature
- 293 K
Properties
- nd
- 1.734000
- Vd
- 51.483018
- glass code
- 734515
- glass status
- preferred
- density
- value: 4030
- thermal expansion
- value: 6.8e-06, temperature range: 243 343
- dPgF
- -0.0101
- k < 0 at some wavelengths in the source data (gain, or a sign convention issue)
References
Cite
NIKON Zemax catalog 2017-11 (obtained from http://www.nikon.com); See also HIKARI 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 408 wavelengths, the same grid as the API and the library| λ (µm) | n | k |
|---|---|---|
| 0.4 | 1.75937 | 0 |
| 0.400561 | 1.759233 | 0 |
| 0.401124 | 1.759097 | 0 |
| 0.401687 | 1.758961 | 0 |
| 0.40225 | 1.758825 | 0 |
| 0.402815 | 1.75869 | 0 |
| 0.40338 | 1.758555 | 0 |
| 0.403946 | 1.758421 | 0 |
| 0.404513 | 1.758287 | 0 |
| 0.405081 | 1.758153 | 0 |
| 0.40565 | 1.75802 | 0 |
| 0.406219 | 1.757888 | 0 |
| 0.406789 | 1.757756 | 0 |
| 0.40736 | 1.757624 | 0 |
| 0.407932 | 1.757493 | 0 |
| 0.408504 | 1.757362 | 0 |
| 0.409078 | 1.757231 | 0 |
| 0.409652 | 1.757101 | 0 |
| 0.410227 | 1.756972 | 0 |
| 0.410803 | 1.756842 | 0 |
| 0.411379 | 1.756714 | 0 |
| 0.411957 | 1.756585 | 0 |
| 0.412535 | 1.756457 | 0 |
| 0.413114 | 1.75633 | 0 |
| 0.413694 | 1.756203 | 0 |
| 0.414274 | 1.756076 | 0 |
| 0.414856 | 1.75595 | 0 |
| 0.415438 | 1.755824 | 0 |
| 0.416021 | 1.755698 | 0 |
| 0.416605 | 1.755573 | 0 |
| 0.41719 | 1.755449 | 0 |
| 0.417775 | 1.755324 | 0 |
| 0.418362 | 1.7552 | 0 |
| 0.418949 | 1.755077 | 0 |
| 0.419537 | 1.754954 | 0 |
| 0.42 | 1.754857 | 0 |
| 0.420126 | 1.754831 | 0 |
| 0.420715 | 1.754709 | 0 |
| 0.421306 | 1.754587 | 0 |
| 0.421897 | 1.754465 | 0 |
| 0.422489 | 1.754344 | 0 |
| 0.423082 | 1.754223 | 0 |
| 0.423676 | 1.754103 | 0 |
| 0.424271 | 1.753983 | 0 |
| 0.424866 | 1.753863 | 0 |
| 0.425462 | 1.753744 | 0 |
| 0.42606 | 1.753625 | 0 |
| 0.426658 | 1.753507 | 0 |
| 0.427256 | 1.753389 | 0 |
| 0.427856 | 1.753271 | 0 |
| 0.428457 | 1.753153 | 0 |
| 0.429058 | 1.753036 | 0 |
| 0.42966 | 1.75292 | 0 |
| 0.430263 | 1.752804 | 0 |
| 0.430867 | 1.752688 | 0 |
| 0.431472 | 1.752572 | 0 |
| 0.432077 | 1.752457 | 0 |
| 0.432684 | 1.752342 | 0 |
| 0.433291 | 1.752228 | 0 |
| 0.433899 | 1.752113 | 0 |
| 0.434508 | 1.752 | 0 |
| 0.435118 | 1.751886 | 0 |
| 0.435729 | 1.751773 | 0 |
| 0.43634 | 1.751661 | 0 |
| 0.436953 | 1.751548 | 0 |
| 0.437566 | 1.751436 | 0 |
| 0.43818 | 1.751325 | 0 |
| 0.438795 | 1.751213 | 0 |
| 0.439411 | 1.751102 | 0 |
| 0.44 | 1.750997 | 0 |
| 0.440028 | 1.750992 | 0 |
| 0.440645 | 1.750882 | 0 |
| 0.441264 | 1.750772 | 0 |
| 0.441883 | 1.750662 | 0 |
| 0.442503 | 1.750553 | 0 |
| 0.443124 | 1.750444 | 0 |
| 0.443746 | 1.750335 | 0 |
| 0.444369 | 1.750227 | 0 |
| 0.444993 | 1.750119 | 0 |
| 0.445617 | 1.750012 | 0 |
| 0.446243 | 1.749905 | 0 |
| 0.446869 | 1.749798 | 0 |
| 0.447496 | 1.749691 | 0 |
| 0.448124 | 1.749585 | 0 |
| 0.448753 | 1.749479 | 0 |
| 0.449383 | 1.749373 | 0 |
| 0.450014 | 1.749268 | 0 |
| 0.450645 | 1.749163 | 0 |
| 0.451278 | 1.749059 | 0 |
| 0.451911 | 1.748954 | 0 |
| 0.452546 | 1.74885 | 0 |
| 0.453181 | 1.748747 | 0 |
| 0.453817 | 1.748643 | 0 |
| 0.454454 | 1.74854 | 0 |
| 0.455092 | 1.748438 | 0 |
| 0.45573 | 1.748335 | 0 |
| 0.45637 | 1.748233 | 0 |
| 0.457011 | 1.748131 | 0 |
| 0.457652 | 1.74803 | 0 |
| 0.458294 | 1.747929 | 0 |
| 0.458938 | 1.747828 | 0 |
| 0.459582 | 1.747727 | 0 |
| 0.46 | 1.747662 | 0 |
| 0.460227 | 1.747627 | 0 |
| 0.460873 | 1.747527 | 0 |
| 0.461519 | 1.747428 | 0 |
| 0.462167 | 1.747328 | 0 |
| 0.462816 | 1.747229 | 0 |
| 0.463465 | 1.747131 | 0 |
| 0.464116 | 1.747032 | 0 |
| 0.464767 | 1.746934 | 0 |
| 0.46542 | 1.746836 | 0 |
| 0.466073 | 1.746739 | 0 |
| 0.466727 | 1.746642 | 0 |
| 0.467382 | 1.746545 | 0 |
| 0.468038 | 1.746448 | 0 |
| 0.468695 | 1.746352 | 0 |
| 0.469353 | 1.746256 | 0 |
| 0.470012 | 1.74616 | 0 |
| 0.470671 | 1.746064 | 0 |
| 0.471332 | 1.745969 | 0 |
| 0.471993 | 1.745874 | 0 |
| 0.472656 | 1.74578 | 0 |
| 0.473319 | 1.745685 | 0 |
| 0.473984 | 1.745591 | 0 |
| 0.474649 | 1.745498 | 0 |
| 0.475315 | 1.745404 | 0 |
| 0.475982 | 1.745311 | 0 |
| 0.47665 | 1.745218 | 0 |
| 0.477319 | 1.745125 | 0 |
| 0.477989 | 1.745033 | 0 |
| 0.47866 | 1.744941 | 0 |
| 0.479332 | 1.744849 | 0 |
| 0.48 | 1.744758 | 0 |
| 0.480005 | 1.744758 | 0 |
| 0.480678 | 1.744666 | 0 |
| 0.481353 | 1.744575 | 0 |
| 0.482028 | 1.744485 | 0 |
| 0.482705 | 1.744394 | 0 |
| 0.483382 | 1.744304 | 0 |
| 0.484061 | 1.744214 | 0 |
| 0.48474 | 1.744125 | 0 |
| 0.485421 | 1.744035 | 0 |
| 0.486102 | 1.743946 | 0 |
| 0.486784 | 1.743857 | 0 |
| 0.487467 | 1.743769 | 0 |
| 0.488152 | 1.74368 | 0 |
| 0.488837 | 1.743592 | 0 |
| 0.489523 | 1.743505 | 0 |
| 0.49021 | 1.743417 | 0 |
| 0.490898 | 1.74333 | 0 |
| 0.491587 | 1.743243 | 0 |
| 0.492277 | 1.743156 | 0 |
| 0.492968 | 1.74307 | 0 |
| 0.49366 | 1.742983 | 0 |
| 0.494353 | 1.742897 | 0 |
| 0.495046 | 1.742812 | 0 |
| 0.495741 | 1.742726 | 0 |
| 0.496437 | 1.742641 | 0 |
| 0.497134 | 1.742556 | 0 |
| 0.497832 | 1.742471 | 0 |
| 0.49853 | 1.742387 | 0 |
| 0.49923 | 1.742303 | 0 |
| 0.499931 | 1.742219 | 0 |
| 0.5 | 1.74221 | 0 |
| 0.500632 | 1.742135 | 0 |
| 0.501335 | 1.742052 | 0 |
| 0.502039 | 1.741968 | 0 |
| 0.502743 | 1.741885 | 0 |
| 0.503449 | 1.741803 | 0 |
| 0.504155 | 1.74172 | 0 |
| 0.504863 | 1.741638 | 0 |
| 0.505572 | 1.741556 | 0 |
| 0.506281 | 1.741474 | 0 |
| 0.506992 | 1.741393 | 0 |
| 0.507703 | 1.741311 | 0 |
| 0.508416 | 1.74123 | 0 |
| 0.50913 | 1.741149 | 0 |
| 0.509844 | 1.741069 | 0 |
| 0.51056 | 1.740988 | 0 |
| 0.511276 | 1.740908 | 0 |
| 0.511994 | 1.740828 | 0 |
| 0.512712 | 1.740749 | 0 |
| 0.513432 | 1.740669 | 0 |
| 0.514153 | 1.74059 | 0 |
| 0.514874 | 1.740511 | 0 |
| 0.515597 | 1.740433 | 0 |
| 0.516321 | 1.740354 | 0 |
| 0.517045 | 1.740276 | 0 |
| 0.517771 | 1.740198 | 0 |
| 0.518498 | 1.74012 | 0 |
| 0.519225 | 1.740042 | 0 |
| 0.519954 | 1.739965 | 0 |
| 0.520684 | 1.739888 | 0 |
| 0.521415 | 1.739811 | 0 |
| 0.522147 | 1.739734 | 0 |
| 0.522879 | 1.739658 | 0 |
| 0.523613 | 1.739581 | 0 |
| 0.524348 | 1.739505 | 0 |
| 0.525084 | 1.73943 | 0 |
| 0.525821 | 1.739354 | 0 |
| 0.526559 | 1.739279 | 0 |
| 0.527298 | 1.739204 | 0 |
| 0.528038 | 1.739129 | 0 |
| 0.528779 | 1.739054 | 0 |
| 0.529521 | 1.738979 | 0 |
| 0.530265 | 1.738905 | 0 |
| 0.531009 | 1.738831 | 0 |
| 0.531754 | 1.738757 | 0 |
| 0.532501 | 1.738683 | 0 |
| 0.533248 | 1.73861 | 0 |
| 0.533996 | 1.738537 | 0 |
| 0.534746 | 1.738464 | 0 |
| 0.535496 | 1.738391 | 0 |
| 0.536248 | 1.738318 | 0 |
| 0.537001 | 1.738246 | 0 |
| 0.537754 | 1.738174 | 0 |
| 0.538509 | 1.738102 | 0 |
| 0.539265 | 1.73803 | 0 |
| 0.540022 | 1.737958 | 0 |
| 0.54078 | 1.737887 | 0 |
| 0.541539 | 1.737816 | 0 |
| 0.542299 | 1.737745 | 0 |
| 0.54306 | 1.737674 | 0 |
| 0.543822 | 1.737603 | 0 |
| 0.544585 | 1.737533 | 0 |
| 0.54535 | 1.737463 | 0 |
| 0.546115 | 1.737393 | 0 |
| 0.546882 | 1.737323 | 0 |
| 0.547649 | 1.737253 | 0 |
| 0.548418 | 1.737184 | 0 |
| 0.549187 | 1.737115 | 0 |
| 0.549958 | 1.737046 | 0 |
| 0.55 | 1.737042 | 0 |
| 0.55073 | 1.736977 | 0 |
| 0.551503 | 1.736908 | 0 |
| 0.552277 | 1.73684 | 0 |
| 0.553052 | 1.736772 | 0 |
| 0.553829 | 1.736704 | 0 |
| 0.554606 | 1.736636 | 0 |
| 0.555384 | 1.736568 | 0 |
| 0.556164 | 1.736501 | 0 |
| 0.556944 | 1.736433 | 0 |
| 0.557726 | 1.736366 | 0 |
| 0.558509 | 1.736299 | 0 |
| 0.559293 | 1.736233 | 0 |
| 0.560078 | 1.736166 | 0 |
| 0.560864 | 1.7361 | 0 |
| 0.561651 | 1.736034 | 0 |
| 0.562439 | 1.735968 | 0 |
| 0.563229 | 1.735902 | 0 |
| 0.564019 | 1.735836 | 0 |
| 0.564811 | 1.735771 | 0 |
| 0.565604 | 1.735705 | 0 |
| 0.566397 | 1.73564 | 0 |
| 0.567192 | 1.735576 | 0 |
| 0.567988 | 1.735511 | 0 |
| 0.568786 | 1.735446 | 0 |
| 0.569584 | 1.735382 | 0 |
| 0.570383 | 1.735318 | 0 |
| 0.571184 | 1.735254 | 0 |
| 0.571986 | 1.73519 | 0 |
| 0.572788 | 1.735126 | 0 |
| 0.573592 | 1.735063 | 0 |
| 0.574397 | 1.734999 | 0 |
| 0.575204 | 1.734936 | 0 |
| 0.576011 | 1.734873 | 0 |
| 0.576819 | 1.73481 | 0 |
| 0.577629 | 1.734748 | 0 |
| 0.57844 | 1.734685 | 0 |
| 0.579251 | 1.734623 | 0 |
| 0.580064 | 1.734561 | 0 |
| 0.580879 | 1.734499 | 0 |
| 0.581694 | 1.734437 | 0 |
| 0.58251 | 1.734376 | 0 |
| 0.583328 | 1.734314 | 0 |
| 0.584147 | 1.734253 | 0 |
| 0.584966 | 1.734192 | 0 |
| 0.585787 | 1.734131 | 0 |
| 0.58661 | 1.73407 | 0 |
| 0.587433 | 1.734009 | 0 |
| 0.588257 | 1.733949 | 0 |
| 0.589083 | 1.733889 | 0 |
| 0.58991 | 1.733828 | 0 |
| 0.590738 | 1.733769 | 0 |
| 0.591567 | 1.733709 | 0 |
| 0.592397 | 1.733649 | 0 |
| 0.593229 | 1.73359 | 0 |
| 0.594061 | 1.73353 | 0 |
| 0.594895 | 1.733471 | 0 |
| 0.59573 | 1.733412 | 0 |
| 0.596566 | 1.733353 | 0 |
| 0.597403 | 1.733294 | 0 |
| 0.598242 | 1.733236 | 0 |
| 0.599082 | 1.733177 | 0 |
| 0.599922 | 1.733119 | 0 |
| 0.6 | 1.733114 | 0 |
| 0.600764 | 1.733061 | 0 |
| 0.601608 | 1.733003 | 0 |
| 0.602452 | 1.732945 | 0 |
| 0.603298 | 1.732888 | 0 |
| 0.604144 | 1.73283 | 0 |
| 0.604992 | 1.732773 | 0 |
| 0.605841 | 1.732716 | 0 |
| 0.606692 | 1.732659 | 0 |
| 0.607543 | 1.732602 | 0 |
| 0.608396 | 1.732545 | 0 |
| 0.60925 | 1.732488 | 0 |
| 0.610105 | 1.732432 | 0 |
| 0.610961 | 1.732376 | 0 |
| 0.611819 | 1.73232 | 0 |
| 0.612677 | 1.732263 | 0 |
| 0.613537 | 1.732208 | 0 |
| 0.614398 | 1.732152 | 0 |
| 0.615261 | 1.732096 | 0 |
| 0.616124 | 1.732041 | 0 |
| 0.616989 | 1.731986 | 0 |
| 0.617855 | 1.73193 | 0 |
| 0.618722 | 1.731875 | 0 |
| 0.619591 | 1.731821 | 0 |
| 0.62046 | 1.731766 | 0 |
| 0.621331 | 1.731711 | 0 |
| 0.622203 | 1.731657 | 0 |
| 0.623076 | 1.731603 | 0 |
| 0.623951 | 1.731548 | 0 |
| 0.624827 | 1.731494 | 0 |
| 0.625704 | 1.73144 | 0 |
| 0.626582 | 1.731387 | 0 |
| 0.627461 | 1.731333 | 0 |
| 0.628342 | 1.73128 | 0 |
| 0.629224 | 1.731226 | 0 |
| 0.630107 | 1.731173 | 0 |
| 0.630991 | 1.73112 | 0 |
| 0.631877 | 1.731067 | 0 |
| 0.632764 | 1.731014 | 0 |
| 0.633652 | 1.730961 | 0 |
| 0.634541 | 1.730909 | 0 |
| 0.635432 | 1.730856 | 0 |
| 0.636324 | 1.730804 | 0 |
| 0.637217 | 1.730752 | 0 |
| 0.638111 | 1.7307 | 0 |
| 0.639007 | 1.730648 | 0 |
| 0.639904 | 1.730596 | 0 |
| 0.640802 | 1.730545 | 0 |
| 0.641701 | 1.730493 | 0 |
| 0.642602 | 1.730442 | 0 |
| 0.643504 | 1.73039 | 0 |
| 0.644407 | 1.730339 | 0 |
| 0.645311 | 1.730288 | 0 |
| 0.646217 | 1.730237 | 0 |
| 0.647124 | 1.730186 | 0 |
| 0.648032 | 1.730136 | 0 |
| 0.648942 | 1.730085 | 0 |
| 0.649852 | 1.730035 | 0 |
| 0.65 | 1.730027 | 0 |
| 0.650765 | 1.729985 | -2.116669e-07 |
| 0.651678 | 1.729934 | -4.645236e-07 |
| 0.652593 | 1.729884 | -7.177351e-07 |
| 0.653509 | 1.729834 | -9.713021e-07 |
| 0.654426 | 1.729785 | -1.225225e-06 |
| 0.655344 | 1.729735 | -1.479504e-06 |
| 0.656264 | 1.729685 | -1.734140e-06 |
| 0.657185 | 1.729636 | -1.989134e-06 |
| 0.658108 | 1.729587 | -2.244485e-06 |
| 0.659031 | 1.729537 | -2.500195e-06 |
| 0.659956 | 1.729488 | -2.756264e-06 |
| 0.660882 | 1.729439 | -3.012692e-06 |
| 0.66181 | 1.729391 | -3.269480e-06 |
| 0.662739 | 1.729342 | -3.526628e-06 |
| 0.663669 | 1.729293 | -3.784137e-06 |
| 0.664601 | 1.729245 | -4.042008e-06 |
| 0.665533 | 1.729196 | -4.300241e-06 |
| 0.666467 | 1.729148 | -4.558836e-06 |
| 0.667403 | 1.7291 | -4.817794e-06 |
| 0.66834 | 1.729052 | -5.077115e-06 |
| 0.669278 | 1.729004 | -5.336801e-06 |
| 0.670217 | 1.728956 | -5.596851e-06 |
| 0.671158 | 1.728908 | -5.857266e-06 |
| 0.6721 | 1.728861 | -6.118046e-06 |
| 0.673043 | 1.728813 | -6.379193e-06 |
| 0.673988 | 1.728766 | -6.640706e-06 |
| 0.674933 | 1.728718 | -6.902586e-06 |
| 0.675881 | 1.728671 | -7.164833e-06 |
| 0.676829 | 1.728624 | -7.427449e-06 |
| 0.677779 | 1.728577 | -7.690433e-06 |
| 0.678731 | 1.72853 | -7.953786e-06 |
| 0.679683 | 1.728483 | -8.217509e-06 |
| 0.680637 | 1.728437 | -8.481602e-06 |
| 0.681592 | 1.72839 | -8.746066e-06 |
| 0.682549 | 1.728344 | -9.010901e-06 |
| 0.683507 | 1.728298 | -9.276108e-06 |
| 0.684466 | 1.728251 | -9.541687e-06 |
| 0.685427 | 1.728205 | -9.807638e-06 |
| 0.686389 | 1.728159 | -1.007396e-05 |
| 0.687352 | 1.728113 | -1.034066e-05 |
| 0.688317 | 1.728067 | -1.060773e-05 |
| 0.689283 | 1.728022 | -1.087518e-05 |
| 0.690251 | 1.727976 | -1.114301e-05 |
| 0.691219 | 1.727931 | -1.141121e-05 |
| 0.69219 | 1.727885 | -1.167978e-05 |
| 0.693161 | 1.72784 | -1.194873e-05 |
| 0.694134 | 1.727795 | -1.221806e-05 |
| 0.695108 | 1.72775 | -1.248777e-05 |
| 0.696084 | 1.727704 | -1.275786e-05 |
| 0.697061 | 1.72766 | -1.302832e-05 |
| 0.698039 | 1.727615 | -1.329917e-05 |
| 0.699019 | 1.72757 | -1.357039e-05 |
| 0.7 | 1.727525 | -1.384200e-05 |
Optical transmission calculator
Free-standing sample in vacuum, normal incidence- Transmittance T
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- Reflectance R
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Fresnel reflection calculator
- Rp
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- Rs
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- R = (Rp+Rs)/2
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- Phase φp
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- Phase φs
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- Brewster angle θB
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- Critical angle θC
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