It's not the first time I've observed this, but thought I would present it as a question to optical experts on the Physics Stack Exchange; I don't understand how it works.
The photograph below shows my eyeglasses, and note the glint reflecting from the bridge, nose support parts of the gold plated frame. When I place the glasses on my face and continue to focus on this glint that comes from an overhead light source, behind my head, I begin to observe something remarkable.
The areas where the glint appears, observed from my eye which becomes very close to the frame become bright circular areas of light that have a similar appearance of images observed under a microscope. I believe the images I am seeing are microscopic images of the surface of the cornea of my eye. There are two reasons I believe this:
(1) there are both circular and rod like structures that I believe are bacteria within the surface fluids, and they appear to be mobile as I slightly move my eye.(different bacteria appear, or else the ones in my view move around much in the same manner as when I move a microscope slide) and
(2) If I squint I can view my eyelashes considerably magnified.
My main question is, how is this happening? I suspect both the eyeglass frame and the eye play a role in some optical system, but is there a way to model this optically and confirm the possible magnification is enough to view bacterial organisms? And why is the focus on the surface of the cornea and not inside the eye?
Best Answer
I suspect that you are getting a focused image of objects that are normally out of focus because of the point like nature of the light source. The spatial coherence of the light means that you can effectively "focus" on these things - and you are adding an amount of magnification because this is like a "pinhole shadowgraph" - the glint being closer to the object (speck of dust, random cell) than that object is to the retina.