Ozirma - near infrared spectrometer

In May, 2021, we found time to work on the V2 !

Let's move to a more powerful MCU, a F4 ! Time to learn USB communication as well, to transfer buffers to the computer !

~200 machine and hand mounted components later, we have a new set of PCB

The 1GOhms Transimpedance amplifier DOES work as expected: bandwidth: 1kHz.

As I recall, I have never spend so much time on so little number of components :)

SNR is around 80dB. We can start measuring the incredibly small signals from the photodiode !

(We have in the best case, ~1V of signal, meaning 1nA in the photodiode: noise is 80dB lower than that.)

We are now measuring, after developing a software toolchain (python / pyqt) spectral data !

Between March and July 2019 we worked on the first prototype !

We started with a small MCU, a F0, and a 10MOhms Transimpedance amplifier for major electronics sub modules.

It was working, in a way ! we learned a lot: the main information was: 10M is not enough !

Wow. After spending few weeks to simulate completely the TIA and searching all over the internet for the perfect opamp (which we found :) ) , we decided to go for the V2

The second important new was: A STM32F0 was well under the needed specs, mainly because we needed bigger data buffers for synchronized acquisitions....

In the meantime, we found a name for this crazy project: OZIRMA.

It's time to start the second prototype :)

2017:

PLASTIC ODYSSEY and Mejdi NCIRI (IMPACT PHOTONICS) come up with a concept that could reduce (a lot) the cost of IR spectrometers for plastic identification using newly available SWIR componants (cheap LEDs and Photodiode).

T3 2018:

For her end-of-studies Internship, Qing CHU (student of l'INSTITUT d'OPTIQUE) build the first proof-of-concept. It may actually work!

T2 2019:

Mejdi NCIRI (IMPACT PHOTONICS), thanks to the funding of PLASTIC ODYSSEY, build the first prototype. It measures spectra, but the SNR and repeatability is not yet sufficient for plastic identification.

Since January 2020:

In between their respective freelance jobs, Vivien HENRY (INDUCTIVE BRAIN) and Mejdi NCIRI (IMPACT PHOTONICS) vow to keep engineering OZIRMA until it can sort plastic.