Laser Power Stabilization

⚠️ Note: This repository contains the complete Python implementation developed for a bachelor thesis project on automated laser power stabilization using NKT Photonics hardware. It provides a fully functional and tested system for performing both calibration and measurement procedures.

Overview

This project presents a comprehensive system for automated power stabilization of a tunable supercontinuum laser, utilizing a Python-based interface alongside real-time feedback algorithms. The system integrates and controls an NKT Photonics SuperK Extreme laser, a SuperK VARIA tunable filter, and a Thorlabs PM100D power meter.

It enables precise calibration and stabilization of the laser output power across a defined wavelength range, and supports automated measurement sweeps with high precision and repeatability.

Objectives

1. Hardware and Software Integration

   • Interfacing with the NKT Photonics CONTROL software using the nkt-tools library.
   • Communicating with the Thorlabs PM100D power meter via PyVISA.

2. Automation of Laser Power Stabilization

   • Implementing an adaptive feedback loop to dynamically adjust laser power.
   • Using calibration data and interpolation to predict optimal power settings.

3. Measurement Routine

   • Executing wavelength sweeps over a user-defined range.
   • Applying calibration-based power corrections in open-loop mode.

4. Graphical User Interface (GUI)

   • A Tkinter-based GUI for real-time interaction.
   • Options for calibration, measurement, data export, and live status monitoring.

Technology Stack

Component	Description
Language	Python 3.9
GUI Framework	Tkinter
Communication	PyVISA, ThorlabsPM100, nkt-tools
Visualization	matplotlib
Control Hardware	NKT Photonics SuperK Extreme, VARIA, CONNECT
Sensing Hardware	Thorlabs PM100D Power Meter

Features

✅ Calibration Routine with power feedback loop
✅ Real-time interpolation for automated measurement
✅ Laser and filter control via Python
✅ Measurement sweep interface with configurable parameters
✅ Graph export and CSV output
✅ GUI with logging and visual feedback

Installation

1. Clone the repository:

   git clone https://github.com/alpsalgur/Laser-Power-Stabilization.git
   cd Laser-Power-Stabilization
   

2. Create and activate a virtual environment:

   python -m venv venv
   venv\Scripts\activate  # On Windows
   

3. Install dependencies:

   pip install -r requirements.txt
   

4. Install the ThorlabsPM100 driver (manually):

   git clone https://github.com/clade/ThorlabsPM100.git
   cd ThorlabsPM100
   python setup.py install
   

Note: The nkt-tools package is available via pip and includes the necessary SDK bindings.

Usage

Start the application with:

python main.py

The GUI will prompt for a target power and allow calibration and measurement across wavelengths.

Acknowledgments

This project was developed as part of a bachelor thesis at Czech Technical University in Prague, supervised by Egor Ukraintsev, Ph.D., and carried out in cooperation with the NKT Photonics CONTROL software platform.