QUESTION: I want to work out how I can magnify an object that is small enough to fit in the eye of a needle/size of a grin of sand...so almost invisible to the naked eye.
I believe I would require a 30 x magnifying lens? However, ideally I want to view the object with just a magnifying glass/lens, NOT a microscope. The magnifying glass/lens need to be fairly small too, a microscope is too big.
Is this scientifically possible? And if so how thick would the glass/lens need to be? The image that is viewed through the glass/lens needs to be in focus and clear.
Any help or information would be very much appreciated.
Thanks so much
ANSWER: Well, the exact magnification you need to see an object in this case will depend greatly on your eyes themselves. The question becomes somewhat subjective. However, the factors in magnification include the curvature of the surfaces of the simple magnifier you wish to construct and its index of refraction. Ideally, you would use something with a very high index, like diamond. As that would be rather expensive, most magnifiers are made of glass (considerably lower index of refraction). See here for a list, keep in mind that not all these materials are clear in the visible spectrum of light: http://en.wikipedia.org/wiki/List_of_refractive_indices
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QUESTION: Thank you for your answer.
Can I just clarify are you suggesting using another material other than glass? I am unsure as to how you could use a diamond in this way.
I have considered using or trying to re-create a jewellers eye loop somehow to view the object, but I am unsure whether or not it is strong enough for something so small.
If a jewellers eye loop is strong enough, would there be a way that I could change the scale of these lenses?Would there be a way to scale down the lens from the jewellers loop? Or is that the smallest strongest type of magnifying glass? Is the glass in microscopes different.
Would reducing the diameter of the lens increases the glass thickness? Or would it mean that the distance between the object and the lens need to be greater?
Is there a way to work out the maths behind this type of magnification?
I am trying to produce a piece of jewellery/small objet with a tiny (invisible to the naked eye) item inside, which isnít visible until you look ideally from the side through the magnifying glass/lens? Potentially it might prove impossible, and perhaps more effective if the lens is on the top of the piece of jewellery/small objet so that you look down into it, would that be fair to say?
I really appreciate your time, I know this must seem like a very strange request. I look forward to your reply.
Yes I am suggesting that, most glass has an index of refraction somewhere around 1.4-1.5. Diamond has an index closer to 2.5, so it bends light better without being as thick. Again, consult the list, it's not the only material that has a high index of refraction. A simple magnifying glass or, as you suggest, jeweler's magnifier, are definitely possible. They'll be more effective with a higher magnification. Just look up the lens-maker's equation on hyperphysics, you'll see where the index of refraction comes in...but trust me, higher is better. Your quest doesn't hinge on the viewer, however, but rather on how you intend on manipulating the object you're trying to create...that's much harder. Micromanipulation is outside my area of expertise, however, you might consult someone familiar with wire-bonding for microchips and such.