There's a tiny world waiting to be discovered! With a few simple materials and tools we can get a glimpse of that world. This laser pointer microscope will let you see the tiny microbes in a drop of pond water. Sound fun? Let's go...
Step 1: Tools and Materials
I used tools and materials that I had on hand- feel free to substitute and improvise. The basic concept is simple- shine a laser through a drop of water and use the water drop's spherical shape as a lens to project an image of the content of the drop onto a flat surface. We will build a frame to hold our laser pointer and aim it at a drop hanging from the end of a syringe. To accomplish that we'll need-
Wood- I used a piece of 1x2 lumber that I had in my shop.
Syringe- I used a 1ml irrigation syringe without a needle
Laser Pointer- This is a cheap laser pointer/flashlight combo from the dollar store.
Binder Clip- I used a 3/4" binder clip to hold the syringe in place.
Scraps of Aluminum Extrusion- I used some scrap bits of aluminum to create a laser holder. I used 1/2" channel stock and 1/2" angle stock that I had around the shop, but you can be creative here- the goal is to hold the laser firmly and to have a way of keeping the button pressed.
You will also need a few tools to make holes and cut materials. I used a power drill and a jigsaw, but you can use whatever you have access to. I also used a screwdriver, hammer, ruler and sandpaper.
Finally, I used screws and fasteners I had on hand. Use what you have.
Step 2: Build the Bottom Frame
The bottom frame will hold the laser and provide a pivot point for the top frame arm. I used a 5" section of the 1x2 lumber. I added a 1 1/2" piece as a spacer and attached it with 1 1/4" 3D finishing nails. I sanded all the cut edges of the wood to prevent splinters.
Step 3: Add the Laser Holder
Now we'll attach the laser holder. I cut a 1 1/2" section of the 1/2" aluminum channel. This will hold the laser loosely. I cut a 1/2" piece of the aluminum angle to act as a shim to hold the laser firm and press the button down. I used sandpaper to smooth the edges of the aluminum pieces. I also drilled two holes with a 7/64" bit and attached the laser holder frame with two #4 x 3/8" phillips pan-head screws.
Step 4: Attaching the Top Frame
I attached another 5" section of the 1x2 lumber to the spacer block with a #8 x 1-1/4" phillips pan head screw. I pre-drilled the piece at one end with an 11/64" drill bit so that the top frame part will swivel. I drilled a pilot hole in the pivot block with a 7/16" bit to prevent the wood from splitting.
Step 5: Adding the Syringe
I drilled a hole to hold the syringe with a 9/32" bit. This is big enough to let the syringe slide up and down in the hole. I used a 3/4" binder clip to hold the syringe at the desired level.
Step 6: Adjusting and Testing the Microscope
Now's time to test it out and adjust it. The syringe can be filled with pond or puddle water now and the laser can be installed and turned on. Push the syringe just enough so that a drop of water hangs down from the tip. The top frame can swivel back and forth and the syringe can be raised and lowered until the drop of water is aligned perfectly with the laser. Point the beam at a white vertical surface and see what happens (this works best in a darkened room). Check out the video above to see the microbes swimming around in a drop of puddle water! Experiment with different water sources.
Warning! These are pretty weak lasers but always use caution- never point it in someone's eye (or your own)!DO NOT POINT A LASER AT AIRCRAFT OR VEHICLES (JAIL IS NOT FUN)! Also, while we used a clean syringe without a needle for this project, never touch a syringe that you find laying around to avoid injury or possible infection. Always use caution when operating power tools or using things with sharp edges. Also, make sure to eat all your vegetables and look both ways when crossing the street!