Over on laserpointerforums.com I ran across a thread discussing using a laser to magnify the critters that live in stagnant water. In this setup there is a syringe containing water from a potted plant, a 250 mW green laser aimed to pass through the drop, and the usual tape and stacks of books needed to dial in these sorts of high precision scientific experiments.
The laser is projected onto a wall 8 feet away, resulting in an image several feet across. An image of biological gadgets, ie bacteria and/or other things that live in stagnate water. I was fascinated, and if you watch the video you’ll see that the guy’s cat is also fascinated. In this experiment the water drop basically acts like a lens, projecting the shadow of the creatures onto the opposite wall. I wonder if the quality could be improved by putting the drop onto a microscope slide and shining the laser through it, followed by a camera or projector lens for magnification?
There is at least one other video like this on youtube, from Arbor Scientific.
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