I would like to know if mirrors have a quality of "resolution" to them like a regular photograph might, or like a JPEG does.
For example, if you looked to closely, or magnified a photograph, you would soon come to a point where the image blurs, or that which was too far away when photographed is not discernible.
If a high quality microscope was applied to a mirror, would it be possible to observe far-away objects reflected by the mirror, taking only the quality and scope of the microscope into account?
Are there different quality mirrors, all other things (e.g. shape) being the same?
Could you also talk about any loss of luminescence if possible?
Also, do all plane mirror have the same converging/diverging power i.e, the image size will be same on all plane mirrors ?
Best Answer
The resolution of a regular photograph is limited by the size of the silver halide crystals in the emulsion, while the resolution of a computer image is limited by the number of pixels used to store it.
However, a typical telescope mirror has no structure bigger than the size of a grain boundary, and this is much smaller than the wavelength of optical light. In this respect there is no finite resolution comparable to a photograph or computer image.
The resolution of a telescope is limited by the size of the mirror rather than by any quality of the reflecting surface. The light reflected by the mirror is diffracted by the mirrors edges forming an Airy disk. This limits the angular resolution to approximately:
$$ \sin \theta \approx 1.22 \frac{\lambda}{d} $$
where $\lambda$ is the wavelength of light and $d$ is the mirror diameter.