Multilayer Mapping UI

A simple desktop UI for multilayer thin-film optical mapping using the transfer matrix method (TMM) and a local optical-constants database based on refractiveindex.info data.

This tool is designed for quick and easy generation of wavelength-angle maps of:

• Reflectivity R
• Emissivity E = 1 - R

It is intended for practical exploration of:

• multilayer thin films
• angle-dependent optics
• infrared emissivity
• thermal-radiation-related optical design
• planar metamaterial / coating prototyping

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Overview

Many TMM-based tools already exist, but they are often code-first or inconvenient for quick visual exploration.

This project focuses on a more accessible workflow:

• simple desktop UI
• direct material selection
• multilayer stack setup without manual scripting
• quick 2D optical mapping
• optional overlay tools for visual analysis
• built-in material-data browsing

The goal is not to replace advanced simulation frameworks, but to make thin-film optical mapping faster and easier to use.

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Main features

• Desktop GUI built with PySide6
• Multilayer thin-film optics using transfer matrix method
• Local optical-constants lookup through a database wrapper
• Generates wavelength-angle maps
• Supports:
  • s polarization
  • p polarization
  • both (average of s and p)
• Switches between:
  • Reflectivity
  • Emissivity
• Optional overlays:
  • Contour
  • Submask
  • Peak
• Built-in material browser for plotting:
  • n(λ)
  • k(λ)
• Export figures as:
  • PNG
  • PDF
  • SVG

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What the program does

The program has two main tabs.

1. Mapping tab

This is the main simulation UI.

You can:

• choose a substrate
• choose the number of layers
• assign a material to each layer
• set layer thicknesses in µm
• define wavelength range and sampling
• define angle range and sampling
• choose:
  • E or R
  • s, p, or both

The program then computes a 2D map over wavelength and incidence angle.

That means you can quickly visualize how a multilayer stack behaves spectrally and angularly, which is useful for:

• emissivity design
• reflectivity analysis
• stack comparison
• thin-film screening

Optional overlays can be enabled to help inspect strong features in the map.

2. Data tab

This tab is for browsing material optical data.

For each material key, the program can display:

• refractive index n
• extinction coefficient k
• wavelength range
• max/min values
• average values over a user-selected wavelength interval

This is useful when selecting candidate materials before building a multilayer stack.

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Physics basis

The program uses the transfer matrix method (TMM) for planar multilayer structures.

For a given stack, it computes the complex reflection coefficient and then evaluates:

• Reflectivity: R = |r|^2
• Emissivity: E = 1 - R

For both polarization, the displayed result is based on the average of the s- and p-polarized reflectivities.

So this tool is mainly suited for:

• planar multilayer optical systems
• angle-resolved reflectivity/emissivity studies
• rapid material/thickness exploration

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File structure

Main files in this project:

• UI.py
  Main entry point. Run this file to start the app.

• TMM.py
  Transfer matrix method engine.

• nkwrap.py
  Optical-constants lookup and interpolation wrapper.

• map_mod.py
  Map-generation logic for reflectivity/emissivity.

• contour.py
  Contour-style overlay generation.

• submask.py
  Submask extraction from map features.

• simplepeak.py
  1D peak detection helper.

• material_keys_tagged.txt
  Tagged material-key list.

• data_f.sqlite
  Local optical-constants database.

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Installation

1. Download this repository.

   • Either download it as a ZIP from GitHub and extract it, or clone it with Git:

2. Download the database file data_f.sqlite from the Google Drive link below:

https://drive.google.com/file/d/13pP8PzNkjb4EwtVwyAV_BmgWK-LTkl8E/view?usp=drive_link

3. Place data_f.sqlite in the same folder as the main Python files.

Your folder should look like this:

Multilayer-Mapping-UI/
├─ UI.py
├─ TMM.py
├─ nkwrap.py
├─ map_mod.py
├─ contour.py
├─ submask.py
├─ simplepeak.py
├─ material_keys_tagged.txt
├─ data_f.sqlite
├─ requirements.txt
└─ README.md

Launch

Run the program with:

python UI.py

This launches the GUI.

Notes

• UI.py is the main entry point of the application.
• data_f.sqlite is required for the material database and optical-constants lookup.
• The database file is not included directly in this repository because of file size.
• If data_f.sqlite is missing or placed in the wrong folder, the program may not work correctly.

Requirements

• Python 3.10+
• numpy
• scipy
• matplotlib
• PySide6

Install dependencies with:

pip install -r requirements.txt