Firmware in hand...

A project log for Compact, $25 spectrometer

AMS's new AS7265X 3-chip set promises a compact, 18-channel, 20 nm FWMH spectrometer for less than $25

Kris WinerKris Winer 05/05/2018 at 00:100 Comments

May 4, 2018

I finally succeeded in getting a reply to my many email inquiries to AMS by addressing my request to the corporate offices in Austria. The very nice Nicole arranged access to the AS7265X firmware for me (a special account is required) and put me in touch with the AS7265X engineer Frank who graciously agreed to try to answer my technical questions about their reference circuit and device operations, etc. Fat city!

As soon as I receive the 3-chip set I ordered from AMS I will be able to assemble and start testing the spectrometer. Woohoo!

I watched the mobile tricorder demo on you tube one more time and noticed they are depending on a MEMS FPI (micro-electromechanical Fabry-Perot interferometer) for spectral information beyond the spectral range of the AS7265X (410 - 940 nm) into the mid IR (1300 - 2000 nm or further). The purpose of using this frequency range is for identification of carbon compounds; this begs the question whether the glucose/sucrose discrimination that seems like magic in the video is possible with just the AS7265X alone. I guess I will find out soon enough.

AMS doesn't seem to have any such MEMS FPI device but Hamamatsu does. The very nice and compact C14272 is such a FP interferometer with < 15 nm resolution from 1350 - 1650 nm. It would make a very nice addition to my $25 Spectrometer, so I asked Hamamatsu about ordering some, but the price is so high even for 100 quantity that my $25 spectrometer would end up being more like a $250 spectrometer! So at least for the first iteration, 410 - 940 nm will have to do...