An open-source, low-cost, high-sensitivity spectroradiometer

General
1

Hi! Im working on making a polarized attachment to this

for @denisedd . And figured while i was looking at a cool open science hardware project I hadn’t heard of, i might as well share it here!

" OSpRad

An open-source, low-cost, high-sensitivity spectroradiometer

Developed by Jolyon Troscianko - 2022

Released under GPL-3.0 license.

This project allows users to build their own low-cost, high-sensitivity spectroradiometer for measuring radiance/irradiance based on the Hamamatsu C12880MA chip. The spectral range of ~310 to 880nm and resoltuion of ~9nm make the OSpRad particularly well suited to visual modelling.

Testing shows that the system can measure spectral radiance down to around 0.001 cd/sqm, and irradiance down to around 0.005 lx.

Included in this project are the 3D STL files for creating your own housing, code for uploading to an arduino nano microcontroller, and a Python app for interfacing with the OSpRad spectroradiometer via desktop computer or Android smartphone (via Pydroid 3).

Code and data are released without any form of warranty, and the author accepts no liability."

4 Likes
2

This is pretty cool. Was it hard to get the C12880MA chip ? How much did it cost ?

3

a quick search: https://store.groupgets.com/products/spectrometer-and-breakout-board-v3
in the order of $234

1 Like
4

Thanks. I should have searched around a bit. That seems pretty reasonable price. Is group gets a reliable website ?

5

they sell through digikey so I assume so:
https://www.digikey.co.uk/en/product-highlight/g/groupgets/c12880ma-breakout-board-with-hamamatsu-c12880-mems-u-spectrometer

1 Like
6

@hikinghack how can i follow along your work on polarized attachment ? Seems I want one of these too :slight_smile:

7

ill try to get me and @denisedd to post what we end up building here in the forums :slight_smile:

2 Likes
8

Having built quite a few spectrometers and sensor systems, I would ask them for some real data on linearity before investing effort in it.

Or, you can prototype the unit and record a fluorescent lamp spectrum at several different exposure times. The lines at 435nm and 546nm are both Hg. Their intensity ratio should be close to 2:1 (435nm is the stronger line) and the ratio should remain constant with different exposure settings.

If you are looking at candidate spectrometers, check this out:

On Linearity and Reproducibility in CCD Spectrometers (Our repo, TCD1304 Sensor with Linear Response, 16 Differential AFE, and active RCT mitigation)