Miscellaneous
Adjustable Focal Length Lens
Adjust the amount of water in this lens to demonstrate changing curvature and resulting focal length changes.
Using the syringe to adjust the amount of water in the lens changes the curvature of the clear flexible membranes and, therefore, the focal length of the lens.
https://www.pasco.com/products/lab-apparatus/light-and-optics/basic-optics/os-8494#specs-panel