While our eyes are miraculous little devices, they aren’t very sensitive outside of the normal old red, green, and blue spectra. The camera in your phone is far more sensitive, and scientists want to use those sensors in place of expensive hyperspectral ones. Researchers at Purdue have a cunning plan: use a calibration card.
The idea is to take a snap of the special card and use it to understand the camera’s exact response to different colors in the current lighting conditions. Once calibrated to the card, they can detect differences as small as 1.6 nanometers in light wavelengths. That’s on par with commercial hyperspectral sensors, according to the post.
You may wonder why you would care. Sensors like this are useful for medical diagnostic equipment, analysis of artwork, monitoring air quality, and more. Apparently, high-end whisky has a distinctive color profile, so you can now use your phone to tell if you are getting the cheap stuff or not.
We also imagine you might find a use for this in phone-based spectrometers. There is plenty to see in the hyperspectral world.
The actual paper’s here: https://ieeexplore.ieee.org/document/11125864
I have no idea why media outlets feel the need to hyperlink random definitions in their text, making it virtually impossible to find the original source to translate their weird analogies.
The odd “your eyes are RGB but camera sensors are better!” comment in the article is super-strange, because, uh, it’s… not true? As in, it’s entirely backwards – camera sensors are just RGB and your eyes aren’t (since you’ve got rods as well). The difference is the sensors output data you can do math on, that’s all. They’re deconvolving the wavelength response of the sensors.
Overall, from the paper, it looks like it’s great for emission lines, okay-ish for wideband spectral shape, and basically no chance for narrow absorption lines.
yeah not so much hyper in that spectrum…. hyper by definition mean beyond: so beyond the normal spectra (as in IR=>VIS=>UV ) normal cameras are by design limited to visible light because that’s what we see. they have IR cutoff filters and the lenses take care of the UV part so no its not hyper-spectral its high resolution spectral at best. so yeah cool tech for sure but this is not hyper-spectral.
“yeah not so much hyper in that spectrum”
Hyperspectral imaging refers to spatially-resolved (as in per-pixel resolved) spectra. It’s “hyper” because the image information has 3 dimensions (intensity, x/y location) and once you add spectral information it’s now a 4-dimensional hypercube. You could also just call it multispectral imaging, but that usually implies a limited number of bands vs. a large number making it seem continuous.
What’s the minimum frequency difference the human visual system can discern between? Kind of tough to measure, but I’ve seen statements of around 1-2 nanometers. Maybe we need a calibration card