Build a Spectrophotometer (Schematics included) as a DIY Project

Posted by – December 26, 2008

I recently ran across this published paper.  Most skunkwork types seem to buy used equipment via ebay.    This article explains how to build a spectrophotometer with schematics, illustrations, and photos.  The circuit is simple:  a photoresistor, op amp, and some mechanics for the optics.

The article even includes a Bill of Materials  (component price list); for the electronics, anyway, and it’s cheap (less than $20 for single quantities through Digikey).  The article is geared towards having undergraduate students build their own laboratory equipment as an educational exercise — and if undergrads can do it, anyone can do it (the article says that a science camp of kids aged 13 to 16 found success).

Education in Chemistry

Build your own spectrophotometer


  • Take a 100 W light bulb, a light-dependent resistor and op amp, a prism or grating in front of a slit, and a curtain – and voilà , a DIY spectrophotometer.
If you build this project or a similar one, leave a comment below.