Fresnel Lens

thingiverse

UPDATE - 06 NOV: Another version is presented for consideration. The original one was divided and based on spherical geometry. This one is a single piece and based on parabolic geometry. This results in a better image from parallel rays, such as those coming from the sun. You can see from the pictures that the focus/intensity is significantly improved. This is slightly smaller than the fully assembled previous one. This size is as large as will fit in my tank all at once. Using the segments, I can make pieces at least twice the size of what I already did. PS - The stripes near the bottom are minor irregularities from the printing process. Due to the angle of the sun, they look overly dramatic. Not to worry. ORIGINAL - 28 OCT: A segmented Fresnel lens is being built. It has a focal length of about seven inches. Now I am just a few bricks, a kerosene lamp, and a rock island short of building a lighthouse. https://en.wikipedia.org/wiki/Fresnel_lens Due to the smallish build volume of my printer, this was made in six interlocking segments. The extra cracks, while not pretty, do not hurt the functionality noticeably.