Build a Pinhole Magnifier

Introduction: Build a Pinhole Magnifier

When I first learned about this device, it was called a "Pinhole Microscope."  I don't think it has enough magnification to be considered a microscope, so I'm just calling it a magnifier.


Clear beverage bottle (a half-liter water bottle in this case)

Dark, opaque plastic piece, large enough to cover the top ot the bottle. (top from a peanut can) Cardboard, like from a cracker box, will also work.


Knife, scissors, or both (Okay, I'm using tin snips.  They were easier to find!)
CA cement (Superglue, Crazy Glue or the equivalent)
Pin (not shown)
Sandpaper (not shown)

Step 1: Cut the Bottle

Cut the neck off the bottle just below where it starts to widen.  This should give you a section about 1" (25mm) long.  Sand the cut edge smooth, so nobody cuts themselves on it.

Step 2: Cut the Disk

Cut a circular piece of your opaque material, just large enough to cover the top of the bottle.

Step 3: Glue

Glue the material over the top of the bottle.  You may want to roughen the bottle top a bit with the sandpaper first.

Once the glue is dry, poke your pinhole in the center of the opaque material.  Start small, it's a lot easier to make the hole larger than it is to try to make it smaller.

Step 4: Finished

Put the object you wish to view under the magnifier, make sure you've got plenty of light, and look through the pinhole!

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    11 years ago on Introduction

    Add a drop of water on top of the pin hole and you will increase the magnification many many times.

    Early magnifiers started as pin holes - this allows your eye to focus at a shorter range. And then moved to using small round glass beads as a lens magnifying many 100's of times.

    Good project. - try the water.


    Reply 11 years ago on Introduction

    Good idea if a plastic top is used, not so good if somebody tries cardboard. In fact, I now recall a version that used clear plastic wrap stretched over the too of a bottle, held in place with a rubber band, and a drop of water placed on the center of the wrap.


    Reply 11 years ago on Introduction

    A bit of nail varnish round the hole in the card would solve the water + card problem :-)