Key benefits Demonstrates how the eye is structured and how vision is formed using a variablecurvature lens. Explains near and far vision and common optical correction methods in a handson, visual way. Serves as an interdisciplinary tool across biology, physiology, and physics teaching, bridging optics and anatomy. Easy to assemble and disassemble, offering a practical learning experience and a sense of accomplishment. Function and features Variablecurvature lens that models the changing focal power of the eye and shows how image formation varies with lens curvature. Clear representation of eyeball structure for classroom demonstration and laboratory observation. Useful for illustrating optical path imaging in physics as well as physiological concepts in biology and hygiene courses. Designed for repeated classroom use and instructional demonstrations. Compatibility and typical settings Designed for use in elementary school nature lessons, junior physiological hygiene classes, school biology and physics courses, and universitylevel teaching. Suitable for teaching and demonstration in hospitals and medical school training environments. Use scenarios Classroom demonstration: Show elementary and secondary students how the eyeball forms images and how near and far vision differ using a visible, adjustable lens. Physics optics lab: Use the device to demonstrate optical path imaging and focal adjustments when covering lens principles in physics curricula. Medical or training session: Use as a handson model in medical education settings to support lectures on ocular structure and optical correction techniques. Assembly and learning value Simple disassembly and assembly process reinforces understanding through handson construction. Assembly activity provides students with practical experience and an immediate sense of accomplishment that supports engagement and retention. Practical notes Intended as an instructional demonstrator rather than a clinical device. Applicable across multiple educational levels and disciplines where explaining eye anatomy and optical principles is required.