Are there any ways to improvise a magnifying glass with common things you could find at any house? (Or if not, less common things that aren't too rare to find.)
For example, in case you have some kind of medicine package and you find yourself trying to read a leaflet with a really small type. In that case, just with a little magnification it would probably suffice.
If you have a smooth, cylindrical drinking glass made of clear glass, you could fill it with water and allow the convex shape of the glass to magnify the object behind it.
Alternately, if you have a clear plastic 2 liter bottle, you can cut off the top part that is rounded, and fill it with water and look down through the water. (Science-sparks.com)
If the reason you are having trouble reading the small type is because you are farsighted/nearsighted, or because it is dark (causing your pupils to dilate and your vision to get fuzzier) you may find it useful to use a pinhole lens.
Make a pinhole in a piece of paper or some other thin object, using a pin, safety pin, or the tip of a knife, and then hold it close to your eye and look through it. The image as viewed through the pinhole will not be magnified, but it will be in focus. The smaller and more regular the pinhole is, the sharper the focus will be (and the darker the image will be, due to less light getting through).
I put a pinhole in one of my credit cards, and sometimes use it to view restaurant menus which I would be unable to read otherwise without glasses due to my farsightedness and the dim light that typically happens in restaurants.
Another thing you can use if necessary is a thumb and two opposite fingers held together to create a tiny triangular hole where they all meet.
Here's a really good video describing several different ways to magnify sunlight to start a fire.
Don't dismiss this as not helpful though -- it gives more than one way to improvise a magnifying 'apparatus'
I'll try and describe with words, but the visual example is linked below.
Take a look, sound isn't necessary if you want to mute the video. About 3:30 long: https://www.youtube.com/watch?v=HCyHC7lnMyQ
Get an old light bulb, the kind with the filament. Break into the bottom of it (the part that spins into the socket) with a screw driver or some such. Be careful to keep the glass intact. After getting the filament out, use a pinch or 2 of salt to clean out the white powder. Swish/swirl it around inside and it'll clean the powder off. Rinse, then refill and you have yourself a curved lens for magnifying.
Get a small bowl/candy dish, the inside should be about the size of your fist. About 2 feet by 2 feet of clear plastic wrap, center the wrap over the bowl, then line the inside of the bowl. Fill the bowl with water about 3/4 full. Then bring the corners of the plastic wrap together, gently lift the water out of the bowl. The water will make the plastic "sag," so carefully twist the top of the plastic so it ends up like a small baggy. Keep twisting until the baggy becomes tight like a ball. Presto! You have yourself a curved lens for magnifying.
Less practical, but it'd work. Take a picture frame without the glass or backing or anything, just the frame. Place it on top of two stands, as if the frame was about to become the top of a table and the stands were the legs of that table. Grab that handy plastic wrap and spread it across the frame nice and smooth. Tape the plastic securely to the frame. This would be the clear, plastic wrap, table top. Slowly pour water onto the plastic and it will sag, creating a lens. Put whatever you want to magnify under the table and look through the water to see it magnified.
Using a water bottle, with water in it. Near the bottom of the bottle or the top of the bottle, you should be able to angle it just right to get a magnified image.
The video uses water and a chemical reaction to create heat, which doesn't address the question at all.
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My own thoughts:
A whiskey glass with just the right amount of water in it. Whiskey because the bottom is already in a concave shape, so the water just increases the effect (I'd imagine)
A cell phone camera with zoom and a steady hand.
Certain flashlights have a magnifying lens in the front to help diffuse/focus the beam of light. You could try taking that off and looking through it.
Would a magnifying mirror do the job? Lots of women carry little makeup mirrors around with them.
Usually, I just take a picture of the label with my phone and then zoom in to the image to read. For example reading nutrition info off a choc/lolly bar the size of my thumb. Zooming in and taking a pic might be better with newer phones I suppose. With this approach, you don't have to carry an additional thing with you when you go the shops and need to read tiny labels.
So if you include a cell phone in your list of common things, the iphone (and if it isnt built in I would be shocked if there wasnt an app for it) sure works best for me. Pro tip: Click the iphone button three times and the magnifier (aka camera with a zoom bar) allows you to slide to enlarge. As an old man I use this technique often! Sadly, what doesn't work at least for me is to actually take a screen shot to demonstrate before and after as the photo comes out blurry , but very easy to read and you can adjust the resolution...
