The Pulsar Engineering

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Polarization Part #6: Calibrating Waveplates

Discover the art of calibrating wave plates with metrology-level precision! Also includes an analysis of the measurement precision using Monte-Carlo simulations!

Luc3rd of April 2026

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Polarization Part #5: Aligning Polarizers

Discover the art of aligning polarizers with metrology-level precision! Covers reference axis alignment, crossed, parallel and 45° configurations.

Luc5th of March 2026

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Polarization Part #4: Generalized Representation of Polarization

Finally a full mathematical framework to understand generalized polarization!

Luc3rd of February 2026

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Polarization Part #3: Birefringence

Understand birefringence and elliptical polarization using our hands-on experimental setup on stress birefringence with vivid colored images!

Luc7th of January 2026

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Optimizing Backlights

Ever wondered how to build a high quality backlight and optimize it through simulation? Check-out our amazing post on backlight optimization!

Luc10th of December 2025

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Measuring and Modelling BSDF of LEDs and Diffusers

Angular Spectrum doesn't ring a bell to you ? Check-out our post on how to measure LED and diffuser plates intensities variation with angle! Also includes CAD files for experimental setups!

Luc10th of November 2025

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Polarization Part #2: Reflection

In this second post of the Polarization series, we explore how reflection affects linear polarization.

Luc9th of October 2025

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Polarization Part #1: Scattering

In this first post of the Polarization series, we explore how scattering affects linear polarization.

Luc21st of September 2025

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Understanding Signed Distance Functions

Discover the amazing world of Signed Distance Functions and how I used it to implement a robust tool crash detection method!

Luc15th of August 2025

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G-Code/CNC Programming

My CNC Programming/G-Code crash course is finally available! Check-it out!

Luc15th of July 2025

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CNC High-Z S400/T Review

I can't believe CNC machining could have been so easy :D Crash course in setting up your own CNC machine for fast optical instrument prototyping!

Luc6th of June 2025

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Rapid Manufacturing of Lens Mounts

Wanting to switch to rapid manufacturing for your optical project? Check here to learn how to make lenses mounts under 3h at less than 6€ each!

Luc6th of May 2025

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#DevOptical Part 31: Cell Mounting of Lenses

DevOps for Optical Design

Luc6th of April 2025

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#DevOptical Part 30: Athermal Doublets

DevOps for Optical Design

Luc7th of March 2025

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#DevOptical Part 29: Apertures as Optical Filters

DevOps for Optical Design

Luc23rd of January 2025

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#DevOptical Part 28: The Achromatic Doublet

DevOps for Optical Design

Luc17th of December 2024

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Confocal Spectrometric Telescope

Watch the spectra of distant objects using a telescope? It's now possible with our open-source confocal spectrometric telescope!

Luc28th of November 2024

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Fluorescence Spectroscopy

Open-Source Fluorescence Spectroscopy, how to create liquid white fluorescence and extracting the fluorescent dyes from pens!

Luc30th of October 2024

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OpenRaman Cuvette Upgrade/Fix

Materialise screwed up my parts! It's time for a fix in the workshop :) .NC program and STEP shared for reproduction!

Luc1st of October 2024

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DIY Linear Translation Stages

Ever wanted a 3-axis translation stage but couldn't afford Thorlabs or Newport prices? Here is the answer! all sort of 3d printed high performances stages!

Luc9th of September 2024

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DIY Camera Test Bench Setup

In this post, I show how an extremely cheap setup based on 3D printing technology can accurately evaluate the performances of cameras according to the EMVA 1288 standard.

Luc9th of June 2024

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The Perception of Colors

Have you ever wondered how we perceive colors and how we reproduce them on computer displays? Here, I give some open-source code to compute colored patch and synthetic spectral images from .csv spectra!

Luc12th of May 2024

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Absorbance Spectroscopy

Open-Source absorbance spectroscopy hardware and experimental discussion of the absorbance of copper chloride in different solvents!

Luc7th of April 2024

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Working with GigE PoE Cameras

Everything you always wanted to know about GigE PoE cameras: from a one camera setup to multiple cameras with multiple computers!

Luc21st of February 2024

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Dynamic Range Analysis of a 350-700nm Spectrometer

Open-Source 350-700nm spectrometer design & analysis of the spectra dynamic range as a function of the slit size!

Luc5th of February 2024

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Exploring Thorlabs MTDEVAL TEC Driver

In this post we "hack" Thorlabs MTDEVAL1 board and software for a cheaper alternative!

Luc6th of January 2024

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#DevOptical Part 27: 50 Shades of Optical Design

DevOps for Optical Design

Luc30th of November 2023

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#DevOptical Part 26: Thin Doublets

DevOps for Optical Design

Luc3rd of November 2023

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#DevOptical Part 25: The Perfect Dialyte

DevOps for Optical Design

Luc4th of October 2023

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Lessons Learned: Dealing with COTS

How should we deal with off-the-shelve components in our product? Discover some lessons learned here!

Luc23rd of September 2023

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#DevOptical Part 24: The Schmidt Corrector

DevOps for Optical Design

Luc15th of August 2023

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#DevOptical Part 23: Plane Windows

DevOps for Optical Design

Luc28th of July 2023

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#DevOptical Part 22: Aspheric Lenses

DevOps for Optical Design

Luc1st of July 2023

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Tuning Thorlabs CPS532 Laser Modes

Transform a cheap $150 Thorlabs laser into a high-performance 1k$+ one!

Luc19th of May 2023

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#DevOptical Part 21: Aplanatic Lenses

DevOps for Optical Design

Luc30th of April 2023

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#DevOptical Part 20: The Anastigmat Singlet

DevOps for Optical Design

Luc31st of March 2023

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CNI MGL-III-532-50mW Laser Review

Testing CNI MGL-III-532-50mW laser on OpenRaman!

Luc11th of March 2023

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#DevOptical Part 19: A Quick Focus Algorithm

DevOps for Optical Design

Luc27th of January 2023

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Laser Longitudinal Modes Tuning

Check here how to tune your laser to boost its performances!

Luc7th of January 2023

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The Most Critical Step in OpenRAMAN

All the secrets to ease up alignment of OpenRAMAN!

Luc20th of December 2022

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#DevOptical Part 18: Thinlenses Aberrations

DevOps for Optical Design

Luc10th of December 2022

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#DevOptical Part 17: The Stop-Shift Equations

DevOps for Optical Design

Luc26th of November 2022

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#DevOptical Part 16: Partition Ratios Revisited

All you need to know about partition ratios!

Luc11th of November 2022

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Fiber-Coupled Laser Update

How to use an external laser in OpenRAMAN!

Luc29th of October 2022

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Asynchronous Resources Management in C++

Resources Manager are NOT only for game engines!

Luc27th of August 2022

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Validating Methenamine Synthesis using Raman Spectroscopy

Is this synthesis correct? Check-out using low-cost Raman Spectroscopy!

Luc7th of July 2022

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#DevOptical Part 15: Paraxial System Tolerance Analysis

DevOps for Optical Design

Luc17th of June 2022

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#DevOptical Part 14: Third-Order Aberration Theory

DevOps for Optical Design

Luc23rd of May 2022

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#DevOptical Part 13: Quantifying the PSF

DevOps for Optical Design

Luc30th of April 2022

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Solid Powder Raman Spectroscopy

OpenRAMAN now with powders!

Luc9th of April 2022

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#DevOptical Part 12: The Paraxial Image Position Formula

DevOps for Optical Design

Luc11th of February 2022

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A concurrent job system in C++ with dependencies

C++ Concurrency in heavy action!

Luc28th of January 2022

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#DevOptical Part 11: The Diffractive PSFs

DevOps for Optical Design

Luc3rd of December 2021

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#DevOptical Part 10: RMS Spot Size

DevOps for Optical Design

Luc11th of November 2021

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#DevOptical Part 9: Geometrical Image Simulation

DevOps for Optical Design

Luc16th of October 2021

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#DevOptical Part 8: Raytracing 101

DevOps for Optical Design

Luc10th of September 2021

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Understanding 3D Transforms

Learn how Video Games and Raytracing software transforms objects from local space to world space coordinates

Luc6th of August 2021

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The Home-Scientist FAQ

Celebrating 20 years of sciences!

Luc24th of July 2021

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#DevOptical Part 7: Replacing Thin-Lenses by Real Lenses

DevOps for Optical Design

Luc18th of June 2021

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#DevOptical Part 6: Telecentric, 4f and Afocal Systems

DevOps for Optical Design

Luc1st of May 2021

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#DevOptical Part 5: Replacing a Thin-Lens by More

DevOps for Optical Design

Luc23rd of April 2021

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#DevOptical Part 4: The Air-Spaced Doublet

DevOps for Optical Design

Luc17th of April 2021

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#DevOptical Part 3: Aperture STOP and Pupils

DevOps for Optical Design

Luc10th of April 2021

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#DevOptical Part 2: Paraxial Raytracing and the ABCD Matrix

DevOps for Optical Design

Luc7th of April 2021

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#DevOptical Part 1: The Real, the Thin and the Thick Lenses

DevOps for Optical Design

Luc6th of April 2021

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#DevOptical Part 0: Introduction

DevOps for Optical Design

Luc2nd of April 2021

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OpenRAMAN LD & TEC Drivers

Complete 400 mA laser & TEC driver below 500€ for OpenRAMAN Performance Edition!

Luc12th of February 2021

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RSA Cryptography Implementation Tips

This post contains all the details you need to know to implement your own Digital Signatures algorithms + Source Code!

Luc17th of November 2020

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Robust Calibration Method for Spectrometers

In this post I present the algorithm I developed for the automated calibration of spectra in OpenRAMAN.

Luc11th of November 2020

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Thorlabs MTD415TE TEC Driver Review

In this post I review the TEC driver MTD415 from Thorlabs. Very good chip for a low price!

Luc10th of November 2020

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Thorlabs LD1255R Laser Driver Review

Short review of Thorlabs LD1255R precision current laser driver. Spoiler alert: it overheats a LOT!

Luc8th of November 2020

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Event Monitoring in C++ Using EVEMON.EXE

How to implement event monitoring in your own C++ programs!

Luc4th of September 2020

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Spectrum Analyzer Software for OpenRAMAN

The official spectroscopy software for the OpenRAMAN project is there!

Luc14th of August 2020

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OpenRAMAN Starter Edition

OpenRAMAN first prototype is available! The perfect solution for teaching Raman spectroscopy at low costs!

Luc17th of April 2020

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OpenRAMAN Spectrometer Efficiency

Measured efficiency is 45%! Great news!

Luc2nd of March 2020

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Evidence of Bisulfite Addition to Aldehydes using Raman Spectroscopy

Does chemistry require faith ? Not anymore! Raman spectroscopy allows you to see into the reactions! Evidence of Bisulfite Addition to Aldehydes using Raman Spectroscopy

Luc2nd of February 2020

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Proportionality of the Least Square Coefficients in Raman Spectroscopy

Follow-up of the previous post on ethyl acetate kinetics! This time I checked how to correlates the coefficients of the LS method!

Luc11th of January 2020

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Measuring Esterification Kinetics using Raman Spectroscopy

Measuring the kinetics of a >1 day organic reaction with OpenRAMAN? Challenge accepted!

Luc28th of December 2019

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Understanding Least-Squares Fitting

Want to understand least squares fitting once and for all? Answer is here!

Luc6th of December 2019

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Quantifying Methanol in Ethanol using Raman Spectroscopy

Is OpenRAMAN able to quantify small amounts of methanol in ethanol? Answer is YES!

Luc16th of November 2019

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Launching OpenRaman DIY Spectrometer !

Check-out our new DIY Raman website on http://www.open-raman.org with full assembly instructions!

Luc29th of October 2019

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Some DIY Raman Spectra

Some free Raman spectra with the final version of the breadboard! Check it out!

Luc16th of August 2019

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Raman Setup Laser Upgrade to 12 cm-1

Raman Spectrometer is now as good as pro units! 12 cm-1 resolution measured on nitromethane and plenty of SNR!

Luc26th of July 2019

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Raman Cuvette Upgrade

New cuvette holder for the Raman breadboard gives 4-fold signal improvement! SNR of ethanol peaks are now >1000:1!

Luc17th of May 2019

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Raman Imaging Lens Upgrade

In this post I am upgrading the lens system of the spectrometer to increase the resolution to 0.15-0.20 nm which will later give peaks of 6 cm-1!

Luc13th of April 2019

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Slit Distortion

Slits can change shape in spectrographs? Wow no way! Discovers here why!

Luc7th of March 2019

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Slit Compression

Slits can change size in spectrographs? Wow no way! Discovers here why!

Luc2nd of March 2019

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DIY Raman Spectroscopy

Do-It-Yourself Raman spectrometer! Discover in this post how to build a Raman spectrometer with 35 cm-1 resolution with off-the-shelves elements.

Luc14th of February 2019

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Choosing the Best Camera Sensor for Spectroscopy

What is the best camera sensor to build a highly sensitive spectrophotometer ? Discover here!

Luc21st of December 2018

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Predicting Thorlabs Achromats RMS Spots Size

Discover a great formula to predict the RMS spot size of any achromatic lens sold by Thorlabs!

Luc18th of December 2018

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Resolution in Spectroscopy

What is resolution in spectroscopy exactly ? How is it different from the dispersive power or even the FWHM of the system ? How can one predict the exact effect of the slit size? Discover all these answers and many more!

Luc8th of December 2018

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Aligning Mill & Vises using Autocollimators

Stop wasting time aligning parts on your mill and discover a great technique to achieve ultra high precision down to 0.01°!

Luc30th of November 2018

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400-800 nm Spectrometer Performances

In this post I present some simulation analysis on the performances on our custom 400-800 nm spectrometer using Ray Tracing software.

Luc25th of August 2018

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Confocal Spectroscopy

In today's post I present a confocal spectrometer that allows you to get spectra at large distance. As illustration, I analyse the composition of a street lamp 50 meters away!

Luc19th of April 2018

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Complete 400-800 nm Spectrometer Design from A to Z

In this post I give a complete spectrometer design and assembly instructions to cover the 400 to 800 nm range with a resolution of 1 nm and a sensitivity of a few photons only.

Luc23rd of March 2018

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Building a Prism Monochromator

In this post, I build a monochromator from a prism to select an output wavelength with a bandwidth of 10 nm and I compare the result with a theoretical model.

Luc13th of February 2018

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Achieving High-Performance Spectroscopy

In this post we learn how optical aberrations affect the maximum achievable resolution and photon efficiency of a spectrometer design.

Luc26th of January 2018

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Linear Variable Differential Transformers

In this post I present a test sensor that measures linear displacements with a resolution better than 50 µm.

Luc21st of November 2017

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Custom 5x Plan Objective from Stock Elements

In this post I present an introduction to optical design with stock elements and I illustrate with a the assembly and testing of a custom 5x microscopy plan diffraction-limited objective.

Luc17th of October 2017

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Building an Autocollimator for the Lab

This video describes how to build a powerful alignment and metrology tool for your optical lab. It provides an accurate reference of infinity (collimated) light and allows to measure very small angles of reflective or semi-reflective (e.g. air-glass) interfaces. Autocollimators are real time-savers in optical labs!

Luc5th of August 2017

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Thin Film Refractometer

In this post I present a refractometer based on total internal reflection on a prism surface that achieves high refractive index resolution. The refractometer is then illustrated with four different solvents.

Luc16th of June 2017

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1 Amp Power LED driver with Modulation Input

In this post I present a high power LED driver with 20 kHz modulation input designed to replace expensive drivers from optical suppliers.

Luc30th of April 2017

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Precision Motorized Translation Table

Precision Motorized tables are often very expensive. In this post, I present a table printed from 3D parts that can provide 80 nm incremental linear motion at only 1.5 mrad wobble.

Luc21st of April 2017

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Essais: Amateur Projects Lifecycle

Working on your own projects is one of the most exciting things that you can do during your spare time. In this post, I share my experience on the methodology of amateur projects management such that you can increase your chances of success.

Luc25th of March 2017

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Low Noise, Adjustable Gain, Photodiode Amplifier

In this post, I describe a generic photodiode amplifier that is compatible with most photodiodes from generic optical supplier. The amplifier has selectable gains up to 70 dB and low noise features.

Luc14th of January 2017

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Generic 8th Order Sallen-Key Filter

In this post I present a downloadable generic PCB for 8th order Sallen-Key filters with examples of low-pass, band-pass and high-pass filters as well as the mathematical development of the Sallen-Key transfer function.

Luc3rd of December 2016

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High-Resolution Spectroscopy

In this post, I describe a spectrophotometer with a 0.01 nm resolution. It is then further applied to the study of lasing modes of a 532 nm NdYAG laser.

Luc4th of November 2016

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A Reference of Optical Infinity

In this post we will see how to align optical element at infinity with high precision and without a reference instrument.

Luc14th of October 2016

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Conductivity Shield for Arduino Uno

This post describes an Arduino Uno based conductometric shield circuit to monitor the conductivity of chemicals in solutions. It includes the Gerber files to reproduce the PCB yourself.

Luc24th of September 2016

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DIY Conductometry

Discover how to build a DIY conductometer for solutions from 30 mS/cm down to demineralized water. The complete Gerber files and circuit schematic provided to help you reproduce the circuit at home.

Luc23rd of July 2016

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Better SNR for Square Wave Signals

In this post, I present a method to extract the RMS value out of a square wave carrier signal such as to maximize its signal-to-noise ratio.

Luc29th of April 2016

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Measuring Small Angles Deviations

In this post, I present a simple device able to measure angular deviations and wedges down to 0.007° using of-the-shelve optical parts.

Luc1st of April 2016

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The Tanks-in-Series Model

In this post, I present the Tanks-in-Series model to approximate a real reactor mixing function by using simple tracer pulse experiments.

Luc13th of February 2016

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Entities, Components and Message Handling in Games

In this post I discuss a message handling system designed for usage in games and which displays a high level of abstraction for the programmer.

Luc17th of November 2015

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Sensitivity of CMOS Pixels

Ever wondered how sensitive CMOS pixels are? Discover the answer here and how it compares to standard high-performance photodiodes!

Luc16th of November 2015

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Building a Microscope from Camera Lenses

In this post, I show how it is possible to build a good quality bright field microscope from inexpensive camera lenses with details down to one micron!

Luc14th of November 2015

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10 Things You Need to Know Before You Buy a Makerbot Replicator 3D Printer

So you are considering buying a Makerbot Replicator 3D printer to help you in your engineering work? Well… maybe it’s not such a good idea. I will tell you why here.

Luc10th of November 2015

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In-line Absorption and Fluorescence Sensor

In this post I describe an inline sensor to measure absorbance and fluorescence of chemicals in flows. I first cover absorbance and fluorescence and how they can be measured using LEDs and photodiodes before introducing a 3D-printed sensor that can track concentration change in flows.

Luc5th of September 2015

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Airsoft Electronic Shooting Targets Game

In this post, I describe an electronic targets system-based game to practice shooting with airsoft guns. The assembly instructions, Arduino source code and internal working principle are given in details so that you can reproduce the system!

Luc4th of August 2015

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Generating Sine Wave from Square Waves

Every student knows that a square wave can be written out of sine waves. Here, we will show how sine waves can be made out of squares waves.

Luc10th of July 2015

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Introduction to Heterodyne Systems

In this post, I give an introduction to heterodyne systems with some working examples and simulations to play with frequency summing and spectrum analysis. Heterodyning is perfect to increase the available bandwidth of your homemade data logger circuits!

Luc7th of June 2015

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Adding an actuated flow selector valve to our syringe pump

In this post I give 3D models and instructions to build an actuated flow selector from 3-ways valves using an HItec servo-motor. We further use this actuated valve to implement a continuous pumping motion from our previous DIY syringe pump.

Luc19th of May 2015

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Arduino Controller for our Low-Cost Syringe Pump

Discover the assembly instructions and source code of our syringe pump controller based on an Arduino Uno board.

Luc13th of March 2015

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Building a Low-Cost XYZ Microscopy Stage

Discover how to print a low-cost XYZ microscopy stage with a 50 µm resolution for a few dollars only. Instructions on video.

Luc8th of March 2015

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Ultra-low Flow Rates with DIY Syringes Pumps

In this post I present a DIY Syringe Pump that you can print for less than $50. The prototype was tested at 12 µl/s and has a 0.6% mean accuracy.

Luc23rd of February 2015

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Camera Lenses as Microscopy Objectives

In this post, I show how expensive microscopy objectives can be efficiently replaced by camera lenses to achieve resolution down to 0.9 µm for less than $150US.

Luc11th of February 2015

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Building a Flow-Controlled Aspiration Pump

In this post, we use a 12V air pump to create a controlled vacuum inside a tank in order to select a desired flow rate for corrosive liquid withdrawal.

Luc2nd of February 2015

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Spectrophotometry Part #3: SLR Lenses

Building of a spectrophotometer can greatly benefits of modern SLR camera lenses. Here, we show how a 50 mm Nikkor SLR lens and an Olympus Plan microscopy objective modifies the quality of a neon spectrum compared to a conventional N-BK7 1" stock lens.

Luc28th of December 2014

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Implementing Object Persistence in C++

Object persistence allows a programmer to store the content of an object into a stream of bytes and to reload the object later. It is conveniently used to implement load/save mechanisms. Here, we study how to implement such a system in a very automated way using C++.

Luc22nd of December 2014

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DIY Magnetic Stirrer

Magnetic stirrer are one of the most important piece of hardware you will find in a chemistry laboratory but they can be expensive. In this article, we study how to build a homemade magnetic stirrer using parts available from online shops.

Luc28th of November 2014

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Working with Pressure Sensors and Load Cells

Pressure sensors and load cells are example of bridge sensors. In this article, we show how to build an instrumentation amplifier for a given sensor.

Luc17th of November 2014

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Building a 5 kHz PIC-based Oscilloscope

No electronics enthusiast can live without an oscilloscope! But they get pretty expensive really fast. Here, we study how to build one from a PIC microcontroller and use the computer to analyze signals up to 5 kHz.

Luc15th of September 2014

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Science-Surplus Spectrophotometer Review

In this review we get a spectrophotometer from Science-Surplus on the trial.

Luc31st of August 2014

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Counting Bubbles with Laplace Pressure

Laplace pressure is an interface force between two immiscible fluids or fluid/gaz. Here, we use the tiny pressure increase in a capillary to count bubbles at rate up to 2,000 bubbles/min.

Luc13th of August 2014

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Following a Fermentation Kinetics by Counting Bubbles

In this post we show how to track a yeast fermentation kinetics from the gaz that escapes the reactor batch. Once the kinetics is known, it is possible to retrieve lots of information such as the alcohol produced or the sugar remaining.

Luc12th of August 2014

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Instancing Objects from Strings in C++

Instancing objects from strings allows you to create class instance from alphanumeric templates. It is quite useful when automatizing loading behaviours such as in game engines.

Luc6th of August 2014

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Hierarchical Collision Detection

Fast collision detection between entities is a major problem in game engine development. In this post I test a technique to speed up the detection by using a hierarchical grid.

Luc5th of August 2014

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Construction of a 400-800 nm Spectrophotometer

Spectrophotometry is the study of the wavelengths composing visible light created or emerging from bodies and chemicals. In this post, I show how to build a spectrophotometer from optical components available online.

Luc7th of July 2014

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Steady Streams in the Lab #1

Achieving steady flowrates can be of uttermost importance in chemistry. Here, we investigate a few techniques that uses only parts available from any DIY shops.

Luc4th of July 2014

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LEDs as Photoreceptors

Most people know LEDs for their light production aspects. But did you know that they can also be used to detect light? Most of all, they show to be sensitive to incoming wavelengths as well which makes them quite useful as sensors...

Luc17th of June 2014

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Over-pressure Electric Valve

When working with pressurized systems, it is often desirable to have a security group to prevent the system to undergo an over-pressure issue. Such an element can also be used to fix the working pressure inside a tank by continuously injecting gas into the tank and letting the excess pressure go out by the security group.

Luc20th of May 2014

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Understanding Quaternion-based Rotations

Complex number allows representing rotations in both 2D and 3D spaces. In this post, we first cover the more simple 2D case before moving to how quaternions works for 3D rotations.

Luc19th of March 2014

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Notes on Turbidity: Biomass Measurements

In this post we compare the turbidity and optical density of yeasts samples at different concentrations.

Luc16th of July 2013

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Understanding Rigid-Body Dynamics

In this post we highlight the fundamentals of rigid body dynamics in the context of computer simulations. Emphasis is put on the origin of the various formula and mathematical expression found.

Luc30th of June 2013

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Flow-rate Controlled Peristaltic Pump

In this post we present a flow-rate controlled peristaltic pump built from parts available online.

Luc24th of May 2013

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Measuring Turbidity

Turbidity is the actual measure of the cloudiness of a solution. It is a known standard for particle counting. Here, we show how to build a simple circuit to measure turbidity from conventional electronics components.

Luc20th of April 2013

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A Finite State Machine-based Biological Reactor

In this post we show a simple model to drive a biological reactor using Finite States Machines and we present some simulation results.

Luc20th of February 2013

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Measuring Liquids Levels by Capacitance

In this post we present a device to measure liquids levels and liquids interfaces by their capacitance.

Luc31st of July 2012

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Data Communication With a PIC Using RS232

Managing a communication between a PIC microcontroller and a PC is a tricky task. Follow this detailed tutorial to understand how to get it right and unleash all the power of RS232 networking!

Luc28th of June 2012

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Measuring Small Capacitances

In this article we show how to measure extremely low capacitance values, down to the femto-farad level by using the deviation of the period from a classical RC astable circuit.

Luc19th of June 2012

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Sine Wave Oscillator with Fewer Op-Amp

Sine wave oscillators are the black magic of electronics. How to build them? How do they work? In this post, we highlight the fundamentals of sine wave generations as well as a technique to reduce the OA costs.

Luc26th of January 2012

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A Trick to Double ADC Resolution

When your ADC resolution is too low for you, just use the ADC resolution doubling trick described here!

Luc24th of November 2011

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Power Functions with Op-Amps

Operational Amplifiers are often use to sum or subtract voltages but they can also be used to produce much more complex functions such a multiply, divide, log and many others. Here, we built a power function from a log and antilog stage.

Luc5th of June 2011

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DIY Flow Sensors

In this post, we measure flow rates by looking at the pressure drop induced by a small orifice in the flow circuit.

Luc1st of December 2010

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Split Power Supply with the TC962

The TC962 from Microchip is one of my favorite integrated circuit. It allows you to produce a negative voltage from a positive supply or to double your supply rails. Here, I show a simple way to create a split power supply from a battery.

Luc6th of September 2010

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Solving Chemical Equilibria on the Computer

Solving chemical equilibria can become very tedious as the number of equations grows. Here, we investigate how to solve complex equations by using the computer to iterate the solutions. Examples and common traps are also presented.

Luc29th of May 2010

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Enhancing Procedural Tiles-Maps Generation

In this post I test a method to generate smooth 2D maps from procedural data by analyzing the local points to select the best tile to use.

Luc14th of November 2009