This paper mainly proposes a simple method to record scattered light rays via photography, presenting a clearer and brighter representation of the optical path. This technique is applied to the double-slit interference experiment and single-slit diffraction experiment typically conducted in general physics courses, and shows the intuitive results concerning the relationship between light intensity and interference or diffraction angle through photographic images. Moreover, a photograph of the optical path presented by a converging lens is provided to better understand visually the phenomena of optical aberration and spherical aberration. The optical path drawing method can be applied to various fields of physics and engineering.

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