Sensor - AS7265x Specifications and Usage

Sensors Imaging
1

Hey everyone!

I’m working on a project where we’re looking to detect allergenic particles in semi-industrial kitchens, and I’m considering using the Triad Spectroscopy Sensor - AS7265x from SparkFun. I’ve got a few questions, and I’m hoping someone here might have some experience or insight:

  1. Using the Sensor at a Distance: Is it possible to use this sensor without having it in direct contact with the sample? If so, what’s a good distance for it to still give accurate readings? And, any ideas on how to get it to work well at distances like 10 to 30 cm from the object?
  2. Fiber Optics: Would it be possible to use fiber optics to carry the light to the sensor while keeping good accuracy? If anyone’s tried this, I’d love to hear how it went!
  3. Precision: Speaking of accuracy—how precise is this sensor in terms of percentage when used under ideal conditions?

Any help or suggestions would be awesome! Thanks in advance for your insights!

2

If you mean the triad spectroscopy sensor, it measures light through three different sensor openings, with six wavelength bands for each of the three sensor ICs, so it is not a good choice for fiber optics. Nor is there a good way to interface a fiber optic cable to any of the individual openings, although it might be possible to glue an SMA fiber optic adapter to one.

Any stray light (that is, not from the sample) will contaminate the measurements.

The data sheet has the specs for the accuracy of the individual wavelength band intensity measurements.

More broadly, how do you imagine that spectroscopic measurements could be used to detect allergenic particles?

3

  1. You do not want it to contact the sample…you want the sensor to be at a steady known fairly close distance, though…I used mine at about 10 cm for this GitHub - TurnerRussell50/Project-Sneaky-Peanut-Butter and it worked. It could be used farther, but everything becomes way more noisy

  2. See above

  3. Eh, it was 100% accurate for my small project lol. It really depends on how tightly you’ve controlled for the known variables (subtract background light signal, etc). Accuracy figures are on page 8, 13 and many more here