Double Convex Lens, Highly polished, optically true lens is excellent for physics classroom demonstrations in optics and light refraction, with ground edges, great for physics classrooms, with highest grade, Size: 500 mm focal length, Lens measures 3in diameter, 0.3 weight
Double Convex Lens, Highly polished, optically true lens is excellent for physics classroom demonstrations in optics and light refraction, with ground edges, great for physics classrooms, with highest grade, Size: 1000 mm focal length, Lens measures 3in diameter, 0.1 weight
Inverting Spectacles, With Two Fully Rotating Inverting Prisms In A Shielded Spectacle Frame, The Inverting Prisms Produce A Lateral Inversion Of The Rays-The World Thus Turns Upside Down, This Also Enables A Better Understanding Of The Visual Perception Of Babies.