To help address this deficiency, we developed a simple, rugged, and low-cost homemade visible spectrophotometer.
The homemade spectrophotometer could be constructed by high school students in physics or chemistry classes using readily
available components.
The total cost of the homemade spectrophotometer is about $25, an eighth of the cost of a
similar device4 and significantly less than commercial units.
The design uses a battery pack, a white light emitting diode (LED) with current-limiting resistor (similar to those in LED
flashlights), a lens, a cuvette and cuvette holder, a grating mounted on a slide, a photodiode mounted on a rotatable arm
using a simple steel hinge, and a digital multimeter.
For ease of alignment and use, we made an “optical table” using half of a 10 in. x 10 in. LEGO baseplate and LEGO construction blocks.
It is exciting for students to perform scientific experiments with familiar materials typically thought of as toys.5 We note that the
University of WisconsinMadison Materials Research Science and Engineering Center has published many exciting and
educational experiments on “Exploring the Nanoworld with LEGO Bricks”. A photo of our homemade spectrophotometer
is shown in Figure 1.