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Many K-12 schools function on limited budgets in their science departments, making it difficult to acquire, maintain, and update microscopes. While modern light microscopes are often complex, expensive, and require specialized training, they are based on simple principles of light. Microscopes enable us to observe objects too small for the naked eye and reveal intricate details. Introducing affordable, easy-to-use microscope adaptations early in education helps foster a deeper understanding of science and encourages young students to pursue STEM fields. Using 3D printing, we developed two innovative microscope models and two lesson plans. Lesson 1: Using a smartphone microscope to visualize microorganisms. Lesson 2: Using a projection microscope to display magnified images of microorganisms using water as the magnifier lens. (1) The smartphone microscope combines a fixed macro lens, smartphone camera, and 3D-printed structure, allowing students to capture high-quality images of various specimens, including prepared tissue slides, live plant and animal samples, and local environmental specimens. A key advantage is that smartphones eliminate the challenge of manual focusing, a common hurdle for beginners, by enabling users to focus on samples with a simple touch of the screen. Additionally, most students already have smartphones, and classes can use them to capture and save images for future reference. (2) The projection microscope uses a laser pointer, coverslip, and 3D-printed model to visualize microscopic content in water samples. This microscope demonstrates the principles of magnification and demystifies microscopy for students because even a tiny drop of water can provide significant magnification. Both microscope models offer cost-effective, easy-to-use alternatives to traditional microscopes, making them ideal for classrooms with limited budgets while engaging students in hands-on scientific exploration.
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TWINKLE: An open-source two-photon microscope for teaching and research
Many laboratories use two-photon microscopy through commercial suppliers, or homemade designs of considerable complexity. The integrated nature of these systems complicates customization, troubleshooting, and training on the principles of two-photon microscopy. Here, we present “Twinkle”: a microscope for Two-photon Imaging in Neuroscience, and Kit for Learning and Education. It is a fully open, high performing and easy-to-set-up microscope that can effectively be used for both education and research. The instrument features a >1 mm field of view, using a modern objective with 3 mm working distance and 2 inch diameter optics combined with GaAsP photomultiplier tubes to maximize the fluorescence signal. We document our experiences using this system as a teaching tool in several two week long workshops, exemplify scientific use cases, and conclude with a broader note on the place of our work in the growing space of open scientific instrumentation.
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- Award ID(s):
- 1734030
- PAR ID:
- 10672190
- Editor(s):
- Pesce, Luca
- Publisher / Repository:
- plos.org
- Date Published:
- Journal Name:
- PLOS ONE
- Volume:
- 20
- Issue:
- 2
- ISSN:
- 1932-6203
- Page Range / eLocation ID:
- e0318924
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1371/journal.pone.0318924
