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arXiv · 2510.04370

Self-Image Multiplicity in a Concave Cylindrical Mirror

Thach A. Nguyen·Kaitlyn S. Yasumura·Duy V. Tran·Trung V. Phan
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Abstract

Concave mirrors are fundamental optical elements, yet some easily observed behaviors are rarely addressed in standard textbooks, such as the formation of multiple reflected images. Here we investigate self-imaging -- where the observer is also the observed object -- using a concave cylindrical mirror. We predict the number of self-images visible from different observation points and classify space into regions by image count. We then test these predictions with an inexpensive stainless-steel concave cylindrical mirror commonly found in teaching labs. This activity links geometrical optics principles to direct observation and provides a ready-to-use classroom demonstration and student exercise.

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Thach A. Nguyen, Kaitlyn S. Yasumura, Duy V. Tran, Trung V. Phan. 2025-10-05. Self-Image Multiplicity in a Concave Cylindrical Mirror. https://arxiv.org/abs/2510.04370

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