[This paper is part of the Focused Collection on Instructional labs: Improving traditions and new directions.] This manuscript presents a case study of an introductory physics student who, during the remote learning conditions imposed during the COVID-19 pandemic, found inspiration within a new, open-inquiry, project-based, laboratory curriculum designed at Portland State University. The phenomenon investigated by the study subject was intriguing to both the student and the lab instructors for its unfamiliar and instructive optical effect: a ring-shaped pattern or halo created by a laser diffusely reflected in a shallow body of water. Drawing on classwork and interview responses, this study shows that the subject achieved many expected curriculum outcomes, particularly with respect to experimental design and data analysis tasks, indicating that the course’s open-inquiry structure can be effective while offering students a free choice of what to investigate in a laboratory class. Additionally, the case study shows that the halo phenomenon is pedagogically rich as it combines refraction, diffuse reflection, and total internal reflection in a nontrivial way, thereby answering calls by physics education researchers for more complex, realistic examples in geometric optics instruction. Finally, this case also highlights challenges students may experience interpreting diffuse reflection and determining the position of optical features beyond image formation, not commonly a focus of introductory physics courses, textbooks, and education research.

中文翻译：

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开放式探究为在家进行有趣的光学实验打开了大门：案例研究

[本文是《教学实验室重点合集：改进传统和新方向》的一部分。] 本手稿介绍了一名物理学入门学生的案例研究，该学生在 COVID-19 大流行期间的远程学习条件下，在波特兰州立大学设计的新的、开放探究、基于项目的实验室课程。研究对象所研究的现象因其陌生且具有启发性的光学效应而引起了学生和实验室讲师的兴趣：由激光在浅水体中漫反射而产生的环形图案或光环。根据课堂作业和访谈反馈，本研究表明该科目取得了许多预期的课程成果，特别是在实验设计和数据分析任务方面，这表明该课程的开放式探究结构可以有效，同时为学生提供自由选择的机会在实验室课堂上进行调查。此外，案例研究表明，光晕现象具有丰富的教学意义，因为它以一种不平凡的方式结合了折射、漫反射和全内反射，从而响应了物理教育研究人员在几何光学教学中提供更复杂、更现实的例子的呼吁。最后，这个案例还强调了学生在解释漫反射和确定图像形成之外的光学特征的位置时可能遇到的挑战，这通常不是物理入门课程、教科书和教育研究的重点。