ASI290MM Mini Spectrometer

thingiverse

I desperately needed a spectrometer right away to measure the spectra of an existing light source and several LEDs that could replace it. I refused to spend a small fortune on a professional instrument, so I started searching for instructions on how to build one using diffraction gratings. I ended up ordering two diffraction gratings (which cost less than a cup of coffee) and began experimenting with a simple webcam, but the results were disappointing due to its color camera limitations. Then it clicked - my little monochrome astrophotography guiding camera had a sensor that was several orders of magnitude better than the webcam's sensor. With just two accessories (a CCTV zoom lens being one of them), I quickly assembled a working prototype and all that remained was designing a sturdy case that could be easily disassembled to remove the camera when needed for astrophotography.\r\n\r\nThe OpenSCAD code here may not be perfect, but I wanted to share it anyway. The main parameter to adjust is the angle between the slit surface and the diffraction grating, which determines the projected wavelength range. I set the angle at 45°, which would put the image center around 700nm.