We have demonstrated both interference and diffraction of a pseudo-double slit using two glass plates with a width and a length of about 5 cm and a thickness of about 5 mm. The plates are attached at the upper and lower ends with Scotch tape of about 0.1 to 0.3 mm between the plates. By adjusting the angle between the two plates, we are able to demonstrate a single-slit diffraction pattern or a double-slit interference pattern. Also we can simulate a changing separation between slits by changing the angle between the plates.
REFERENCES
1.
Three pseudo-double slits like the Lloyd mirror, Fresnel double mirror, or Fresnel double prism are well described in typical optics textbooks, for example, in Eugene Hecht,
Optics
, 4th ed. (Pearson
, 2002
), pp. 398
–400
.2.
Robert D.
Polak
, Nicolette
Fudala
, Jason T.
Rothchild
, Sam E.
Weiss
, and Marcin
Zelek
, “Easily accessible experiments demonstrating interference
,” Phys. Teach.
54
, 120
(Feb.
2016
).3.
Mark
Welter
, “Interference of laser light using a lab beaker
,” Phys. Teach.
54
, 505
(Nov.
2016
).4.
Dave
Van Domelen
, “Binder clip optics bench for Young’s double-split experiment
,” Phys. Teach.
50
, 116
(Feb.
2012
).5.
Bettina
Teng
, Peter
Teng
, and Charles H.
Hennekens
, “A simple way to teach single slit diffraction based on edge diffraction
,” Phys. Teach.
56
, 380
(Sept.
2018
).6.
There are many suppliers, for example, Knight Optical, https://www.knightoptical.com/.
7.
ImageJ is a Java-based image processing program developed at the National Institutes of Health and the Laboratory for Optical and Computational Instrumentation (LOCI, University of Wisconsin). You are able to get an intensity profile along the line that you draw on any JPEG file opened by the ImageJ program, https://imagej.net/Welcome.
8.
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2020
American Association of Physics Teachers
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