In this paper, we discuss a demonstration we have been performing for years with students from different levels, from physics students from our university to high school students in some talks aimed at encouraging them to study science. It provides visualization of Brewster’s angle in an ingenious way using a “loaded” liquid crystal display (LCD) monitor lacking its front polarizing filter. The demonstration is based on observing the hidden image of this loaded LCD reflected in a transparent plate. In some way, we deal with a reverse version of what happens when a vampire faces a mirror and sees no reflected image of himself.

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Readers can access the Appendix at TPT Online at https://doi.org/10.1119/5.0063687, under the Supplemental tab.
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7.
The experiments presented here can be performed with most LCD devices (TVs, computers, laptops, or smartphones with liquid crystal displays), in which the last (front) polarizer is placed on top of all the layers (except for a protective window), including the RGB color filters, once this front polarizer is removed.

Supplementary Material

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