Background: To really understand instrumentation, one must build and characterize an instrument. Seeing how an instrument behaves in reality as opposed to how it should behave theoretically is eye-opening. The instrument you will build has all the components of a "real" spectrophotometer, but is made from readily-available, inexpensive parts. It will be able to measure absorbance in the visible region of the spectrum, but it will not be able to do so very well. In seeing where it fails, you will learn how one must engineer a laboratory-grade instrument. You will gain appreciation for how well those instruments work – while understanding that they, too, are imperfect.
Kathleen Kelley, graduate student at Illinois, made major contributions to designing the instrument, suggesting samples, and designing the laboratory activities.
THIS IS A FIRST DRAFT DOCUMENT. MORE DIAGRAMS AND PICTURES WILL BE ADDED LATER. STUDENT SUGGESTIONS FOR IMPROVEMENTS WOULD BE MOST WELCOME
Cell Phone Spectrophotometer
V.1.1 June, 2009
Alexander Scheeline, University of Illinois at Urbana-Champaign