What Can You See When You Look at a Mirror Under a Microscope?

[rkatcosmos]

If a piece of mirror is observed under a high magnification optical microscope, then what would one see??

 

[Bobbywhy]

If a piece of mirror is observed under a high magnification optical microscope, then what would one see??

rkatcosmos, Welcome to Physics Forums!

Good question! My answer is: “It depends on what kind of mirror you are looking at.” There are two major types of mirrors. First is the common household mirror where the rear surface is reflective and the substrate is transparent; often it is glass. What you see with a high power microscope would depend on where your focus was set: beginning at the front surface of the transparent glass one could selectively move the focus down through the glass thickness all the way to the rear reflective surface.

The second type of mirror is the front surface mirror where the reflective coating is on the first (front) surface. On this type of mirror you may expect to see surface defects like scratches or imperfections in the coatings. Also, what you see would depend on the type of mirror you are examining. There are many types of first surface mirrors. For instance, here is a selection of one supplier of mirrors, Edmund Optics:

“Specialty mirrors: 15 types
Laser mirrors: 10 types
Infrared Mirrors: 10 types
Focusing mirrors: 12 types
Flat mirrors: 22 types”
http://www.edmundoptics.com/optics/optical-mirrors/

 

[johnbbahm]

Most reflective surfaces are ether sputtering or Vacuum deposition.
Ether with a front surface or a back surface mirror, I think you will
see the defects in the glass before anything else.
The molecules of material from ether method are too small to see
with an optical microscope.

 

[technician]

I think you will seee your eye !

Try it... it is easy enough

 

[Bobbywhy]

I think you will seee your eye !

Try it... it is easy enough

Oh, technician! Interesting thought you've had! Have you done it yourself? Why not share your results with all of us here?

 

[Claude Bile]

You will not see your eye because the illumination arm of the microscope is different to the "observer" arm.

You actually see the conjugate focal plane in the illumination arm of the microscope.

I doubt you would see the surface of the mirror as the specular reflection will be much greater than the diffuse reflection (or scatter) off the mirror surface itself.

This thought experiment is a good demonstration as to why quality optical microscopes have the source in the Fourier plane; basically so you don't image the source (a bulb filament, say) on top of the regular image. Look up Kohler illumination for more info.

Claude.

 

[technician]

I have to admit that all I tried was a powerful magnifying glass and yes...I saw my eye.
Have not tried a microscope...yet.