Inquiry with Laser Printer Diffraction Gratings Available to Purchase

The pages of The Physics Teacher have featured several clever designs for homemade diffraction gratings using a variety of materials—cloth,¹ lithographic film,² wire,³ compact discs,⁴ parts of aerosol spray cans,⁵ and pseudoliquids and pseudosolids.⁶ A different and inexpensive method I use to make low-resolution diffraction gratings takes advantage of specialty transparency film designed for use with laser printers. A standard laser printer can print black lines (separated by a white line) at 60 black lines/cm (about 150 lines/in), which is a small enough spacing to produce a crude diffraction grating [see Fig. 1(a)] that is sufficient for the physics inquiry activities described in this paper.