Convergent and divergent lenses

thingiverse

Supports to make very simple convergent (convex) and divergent (concave) lenses for educational or leisure purposes. Each support is composed of two carved guides which can host two sheets of plastic and of two opposite walls which delimit a tub. Basically, you can cut two small flat rectangles of thin transparent plastic (PET is perfect) having dimensions so that they fit in the guides along the base and the walls of the support (the base lenght should be that of the horizontal guide and the height should be slightly higher than that of the walls). You might consider to glue the plastic sheets to the support once you place them in the guides, but they should be fixed enough already. To turn your work into a real lens you only have to fill the tub between the walls and the plastic sheets with water. The support might not be watertight, so you might need to refill the tub from time to time due to leakages. I recommend to set a lower print speed especially for the higher levels. This is to avoid that the vertical guides along the walls are filled with filament due to non-extruding fast movements. See the post-printing section below for further details. Observing something across the filled lens, a convex convergent lens will magnify it, while a concave divergent lens will reduce it.