Features

Basic operation

Slider bars and up / down buttons can be used to quickly change layer thickness and film material, and changes are immediately reflected in the graph.
Tabbed sheets allow you to overlay up to 20 film designs on a graph.

3D chart

You can display a 3D graph with a spectral variable, such as wavelength, and the angle of incidence on the x and y axes.
You can set the contour lines.
It is also possible to rotate and zoom with the mouse.

Optical monitoring

You can simulate optical monitoring while accounting for the tooling factor and the in situ refractive index (n) and extinction coefficient (k).
Information for all layers can be displayed simultaneously.

Supported monitoring methods

Electric field intensity

The electric field intensity distribution can be displayed for each polarization component.

The electric field intensity distributions for light incident from the front and back sides can be displayed simultaneously.

Color calculation

Color differences can be calculated between two designs or between the front and back sides.

Color spaces, colorimetric quantities, and color difference formulas

XYZxy, CIE L*a*b*, L*C*h, Hunter Lab, L*u*v*, UCS, Whiteness Index, Yellowness Index, sRGB, CIEDE2000, Dominant Wavelength.

Supported illuminants

A, B, C, D50, D55, D65, D75, E, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12, ID50, ID65.
You can also register your own light source data as a csv file.

Manufacturing error analysis

Evaluates how variations in layer thickness, refractive index, and extinction coefficient affect optical performance.

Monte Carlo simulation of spectral characteristics

Monte Carlo simulation of color

You can specify variations in layer thickness, refractive index, and extinction coefficient separately for each layer.
The variation can follow a uniform distribution in absolute values, a uniform distribution in percentages, or a normal (Gaussian) distribution specified by σ.
We use the Mersenne Twister method to generate random numbers.

Group Delay and Dispersion

In the calculation of group delay, differentiation also includes the optical constants (the dispersion formulas of n and k).
Numerical differentiation (finite difference) with large errors is not used.

Stack

You can calculate the combined optical characteristics of multiple plane-parallel substrates with coatings on their surfaces.

Reverse side

The optical characteristics for light incident from the front and back sides can be displayed simultaneously.

Inhomogeneity

Hover over an "Inhomo..." cell to display the inhomogeneity profile in a pop-up window.

Repeated layer groups

Repeated layer groups are displayed clearly.
You can set a thickness multiplier for the layers within each group.

Optimization

Optimization(1) Standard mode

Standard mode offers three search methods: local search, global search, and needle search.
You can use spectrophotometer data as the target to estimate layer thickness differences between the design and the measured coating.

Local search

Optimizes layer thicknesses with a fixed number of layers. Displays a single result.
Local search uses the Levenberg-Marquardt method for optimization.

Global search

Optimizes layer thicknesses with a fixed number of layers. Displays multiple results.
Global search combines simulated annealing with the Levenberg-Marquardt method for optimization.

Needle search

Needle search uses needle synthesis and Gradual Evolution to optimize the design while increasing the number of layers and the total optical thickness.

Optimization(2) Free-hand mode

Drag near the selected curve with the left mouse button to reshape it. Optimization starts automatically when you release the button.

n and k calculation for substrate and film

This function calculates n and k of a substrate or single-layer film from the measured values of spectral reflectance and spectral transmittance.

1. Calculate refractive index of substrate without absorption
   Calculate the refractive index of an uncoated, non-absorbing substrate from its single-surface reflectance, total reflectance from both surfaces, or transmittance.
2. Calculate refractive index, extinction coefficient and internal transmittance of substrate
   Calculate the refractive index, extinction coefficient, and internal transmittance of an uncoated, absorbing substrate from reflectance or transmittance measurements. Measurements of both a substrate with one matte surface and a substrate polished on both sides are required.
3. n and k analysis of single-layer film
   Determines the refractive index (n), extinction coefficient (k), and thickness (d) of a single-layer film by fitting calculated spectral reflectance and transmittance to measured data using dispersion formulas.
   Added an option to analyze only normal dispersion (dispersion in which the refractive index increases as the wavelength becomes shorter).
   Front reflectance, back reflectance, and transmittance data can now be analyzed together even if their wavelengths and numbers of measurement points differ.
4. Calculate n and k of single-layer metal film
   Calculate n and k of the metal film from reflectance measured from the front and back sides. The metal film must be thick enough to have zero transmittance.

Spectrophotometer data

You can import spectrophotometer measurement files and display the data on the chart.
Relative reflectance measurements can be converted to absolute reflectance when imported.

Supported file formats

Hitachi UV-Solutions files and UV1 files(*.UDSS, *.UDS, *.UDA, *.UV1),
Shimadzu SPC files,
Olympus-USPM files(*.dat, *.csv),
Jasco JWS files,
Ocean-Optics OOi-Base32 files,
csv files,
tab separated text files.

Dispersion

Substrate

Data for 1,381 substrate materials are included.

SCHOTT, OHARA, HOYA, SUMITA, HIKARI, CDGM
APEL, ZEONEX, PMMA, Polycarbonate, etc.
You can also register your own data.

Film material

The following 33 types of materials are registered.

Ag, Al2O3, AL, Au, Cr, Cu, H2, H4, LaF3, M3, M3-RT, MgF2, Nb2O5, Nb2O5-RT, OH5, OH5-RT, OS50, OS50-RT, SiO2, Ta2O5, Ta2O5-RT, Ti, TiO2, Zn, ZnS, ZrO2, Cytop

Al2O3(KTM), HfO2(KTM), LaF3(KTM), Ti3O5(KTM), ZrO2(KTM), ZRT2(KTM)
KTM: Kyoto Thin-Film Materials Institute

You can also register your own data.

Types of dispersion formulas

Dispersion formulas of refractive index n

• Sellmeier
  \[n(λ) = \sqrt{ 1 + {A_0λ^2 \over λ^2-A_3} + {A_1λ^2 \over λ^2-A_4} + {A_2λ^2 \over λ^2-A_5} } \]
• Sellmeier2
  \[n(λ) = \sqrt{ 1 + A_0 + {A_1λ^2 \over λ^2-{A_3}^2} + {A_2 \over λ^2-{A_4}^2} } \]
  * A₂ does not have λ².
  
  
• Sellmeier3
  \[n(λ) = \sqrt{ 1 + {A_0λ^2 \over λ^2-A_4} + {A_1λ^2 \over λ^2-A_5} + {A_2λ^2 \over λ^2-A_6} + {A_3λ^2 \over λ^2-A_7} } \]
• Sellmeier4
  \[n(λ) = \sqrt{ A_0 + {A_1λ^2 \over λ^2-A_3} + {A_2λ^2 \over λ^2-A_4} } \]
• Sellmeier5
  \[n(λ) = \sqrt{ 1 + {A_0λ^2 \over λ^2-A_5} + {A_1λ^2 \over λ^2-A_6} + {A_2λ^2 \over λ^2-A_7} + {A_3λ^2 \over λ^2-A_8} + {A_4λ^2 \over λ^2-A_9} } \]
• SellmeierT1
  \[n(λ) = \sqrt{ A_0 + {A_1λ^2 \over λ^2-A_2} } \]
• SellmeierT2
  \[n(λ) = \sqrt{ A_0 + {A_1λ^2 \over λ^2-A_2} + A_3λ^2 } \]
• SellmeierX1
  \[n(λ) = \sqrt{ 1 + {A_0λ^2 \over λ^2-{A_3}^2} + {A_1λ^2 \over λ^2-{A_4}^2} + {A_2λ^2 \over λ^2-{A_5}^2} } \]
• General1
  \[n(λ) = \sqrt{ A_0 + A_1λ^2 + {A_2 \over λ^2} + {A_3 \over λ^4} + {A_4 \over λ^6} + {A_5 \over λ^8} + A_6λ^4 } \]
• General2 (Old Schott)
  \[n(λ) = \sqrt{ A_0 + A_1λ^2 + {A_2 \over λ^2} + {A_3 \over λ^4} + {A_4 \over λ^6} + {A_5 \over λ^8} } \]
• Cauchy
  \[n(λ) = A_0 + {A_1 \over λ^2} + {A_2 \over λ^4} \]
• Hartmann1
  \[n(λ) = A_0 + {A_1 \over λ - A_2} \]
• Hartmann2
  \[n(λ) = A_0 + {A_1 \over (λ - A_2)^2} \]
• Herzberger
  \[n(λ) = A_0 + A_1 λ^2 + {A_2 \over (λ^2 - 0.168^2)} + {A_3 \over (λ^2 - 0.168^2)^2} \]
• Herzberger2
  \[n(λ) = A_0 + {A_1 \over (λ^2 - 0.028)} + {A_2 \over (λ^2 - 0.028)^2} + A_3 λ^2 + A_4 λ^4 + A_5 λ^6 \]
• QUAD
  \[n(λ) = A_0 + {A_1 \over λ^2} \]
• QUADSK
  \[n(λ) = A_0 + A_1 λ + A_2 λ^2 \]
• Conrady
  \[n(λ) = A_0 + {A_1 \over λ} + {A_2 \over λ^{3.5}} \]
• Handbook1 (Handbook of Optics)
  \[n(λ) = \sqrt{ A_0 + {A_1 \over (λ^2 - A_2)} - A_3λ^2 } \]
• Handbook2 (Handbook of Optics)
  \[n(λ) = \sqrt{ A_0 + { A_1 λ^2 \over (λ^2 - A_2)} - A_3λ^2 } \]
• Extended (ZEMAX)
  \[n(λ) = \sqrt{ A_0 + A_1λ^2 + {A_2 \over λ^2} + {A_3 \over λ^4} + {A_4 \over λ^6} + {A_5 \over λ^8} + {A_6 \over λ^{10}} + {A_7 \over λ^{12}} } \]
• Extended2 (ZEMAX)
  \[n(λ) = \sqrt{ A_0 + A_1λ^2 + {A_2 \over λ^2} + {A_3 \over λ^4} + {A_4 \over λ^6} + {A_5 \over λ^8} + A_6 λ^4 + A_7 λ^6 } \]
• Extended3 (ZEMAX)
  \[n(λ) = \sqrt{ A_0 + A_1λ^2 + A_2λ^4 + {A_3 \over λ^2} + {A_4 \over λ^4} + {A_5 \over λ^6} + {A_6 \over λ^8} + {A_7 \over λ^{10}} + {A_8 \over λ^{12}} } \]
• Buchdahl
  \[n(λ) = A_0 + A_1 ω(λ) + A_2 ω(λ)^2 \] \[ω(λ) = { λ - A_3 \over 1 + 2.5(λ - A_3) } \]
• DRUDE
  \[{n^2}(λ) - {k^2}(λ) = A_0 - { A_1 {A_2}^2 λ^2 \over λ^2 + {A_2}^2 } \]
• LorentzianK
  \[n(λ) = \sqrt{ A_0 + {k^2}(λ) + A_1 λ^2 {(λ^2 - {A_2}^2) \over (λ^2 - {A_2}^2)^2 + {A_3}^2 λ^2 } } \]
• Forouhi-Bloomer
  \[n(E) = n(∞) + {B_0E+C_0 \over E^2 - BE + C} \] \[B_0 = {A \over Q}{({-B^2 \over 2} + E_gB - {E_g}^2 + C)} \] \[C_0 = {A \over Q}{\left(({E_g}^2 + C){B \over 2}-2E_gC\right)} \] \[Q = {1 \over 2}{(4C-B^2)}^{1 \over 2} \] \[E= {{hc} \over λ} \]
  h: Planck's constant, c: speed of light; E is expressed in eV.
  n(∞), Eg, A, B, C: Material constants (parameters of the dispersion formula)
• A₀, A₁, A₂, A₃, A₄, A₅, A₆, A₇, A₈, A₉: material constants.
  The unit of λ is μm (excluding Forouhi-Bloomer).

Dispersion formulas of extinction coefficient k

• Sellmeier
  \[k(λ) = {\biggl[ n(λ) \biggl(B_0 λ + {B_1 \over λ} + {B_2 \over λ^3} \biggr) \biggr]}^{-1} \]
• Cauchy
  \[k(λ) = B_0 + {B_1 \over λ^2} + {B_2 \over λ^4} \]
• Exponential
  \[k(λ) = B_0 \cdot exp(B_1 λ^{-1}) \]
• QUADSK
  \[k(λ) = B_0 + B_1 λ + B_2 λ^2 \]
• DRUDE
  \[2n(λ)k(λ) = { A_1 A_2 λ^3 \over λ^2 + {A_2}^2 } \]
• LorentzianK
  \[k(λ) = \sqrt{ {0.5 \over n(λ)} \cdot {A_1 A_3 λ^3 \over (λ^2 - {A_2}^2)^2 + {A_3}^2 λ^2 } } \]
• Forouhi-Bloomer
  \[k(E) = {A(E-E_g)^2 \over {E^2 - BE + C}} \] \[E= {{hc} \over λ} \]
  h: Planck's constant, c: speed of light; E is expressed in eV.
  Eg, A, B, C: Material constants (parameters of the dispersion formula)
• B₀, B₁, B₂: material constants.
  The unit of λ is μm (excluding Forouhi-Bloomer).

Misc calculator

The thin film calculator provides simple calculations for thin films.

Refractive index

Calculate the refractive index of a single-layer film from the reflectance peak corresponding to a quarter-wave optical thickness (QWOT), measured with a spectrophotometer.

Two surfaces

Calculate the combined reflectance of two surfaces, including multiple reflections under incoherent conditions.

Three-layer equivalent film

Calculate the layer thicknesses of a three-layer coating with two different refractive indices that has the same reflectance as a quarter-wave optical thickness (QWOT) layer.

Change log

Go to Change log