“In High School Chem Labs, Every Cameraphone Can Be a Spectrometer” on Wired.com. [via adafruit]
University of Illinois chemistry professor Alexander Scheeline has developed software that turns a camera phone, an LED, and a few other cheap tools into a spectrometer. Armed with these, he thinks we can bring high-end analytic tools to high school chemistry labs all over the world.
Purpose-built spectrophotometers are essential tools in analytic chemistry. By measuring the electromagnetic spectrum a substance absorbs or emits, you can determine its molecular composition. Theyâ€™re also expensive, which is why theyâ€™ve generally been confined to universities. Scheeline has already brought his cellphone spectrometers to high schools in Atlanta and Hanoi. Other high-school chemistry and physics teachers doing professional development at Illinois have also brought Scheelineâ€™s tools to their classrooms.
Initially, Scheeline hadnâ€™t been looking for ways for students to use their phones in class. Instead, he wanted students to build their own spectrophotometry tool, to better understand their instruments and their limitations. Putting together the LED as a light source, diffraction gratings and cuvettes were easy; finding a small sensor to capture the light was hard.
â€œAll of a sudden this light bulb went off in my head: a photodetector that everybody already has! Almost everybody has a cellphone, and almost all phones have a camera,â€œ Scheeline said. â€œI realized, if you can get the picture into the computer, itâ€™s only software that keeps you from building a cheap spectrophotometer.â€