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Similarities and Differences
Because common principles underlie the working of every type of mirror, they all operate in the same way. A beam of electromagnetic radiation hits the mirror coming in at a given angle. The beam is reflected away at the same angle relative to the mirror, but in the opposite direction. For example, a beam hitting a mirror at an angle of 5 degrees above a line perpendicular to the mirror's surface is bounced out at an angle of 5 degrees below the perpendicular line.
The difference among the types of electromagnetic radiation is all in their wavelength. The wavelength of electromagnetic radiation is connected to the energy contained within a packet of that radiation: the shorter the wave, the higher the energy. Radio waves can be as long as 1,000 meters -- more than half a mile long; visible light is about half-a-millionth of a meter long; X-rays are less than one-billionth of a meter long. So one packet of X-rays is about 5,000 times more energetic than a packet of visible light, and light is as much as 2 billion times more energetic than radio waves.
X-Ray Mirrors
X-rays are so powerful that they plow right into most atoms and get absorbed. If you point an X-ray flashlight at your bathroom mirror, most of the energy would be absorbed in the reflective coating. If you took that X-ray flashlight, though, and tilted it so the beam just barely glanced off the mirror, you could get the X-ray to bounce off. That's called a grazing incidence mirror, and it's the type used by X-ray imaging space telescopes. Because X-rays are so short, the surfaces of an X-ray mirror need to be very smooth.
Optical Mirrors
There are two basic types of optical mirrors: dielectric and metallic. When you look at the reflection off of a pond you're seeing dielectric reflection, while your bathroom mirror is an example of metallic reflection -- the back of the glass is covered by a metallic paint. Optical mirrors can be used near normal incidence -- that is, with the light beam coming in almost perpendicular to the surface. That makes it relatively easy to form them into useful shapes, such as the reflective mirror in the headlights of your car. When a mirror is to be used to create images, as in a telescope or microscope, the final surface -- with errors and flaws from the manufacturing process -- must be within a few billionths of a meter of the perfectly designed mirror.
Radio Mirrors
Radio reflects off just about any metal surface. To make a useful radio wave mirror, though, you need to make an image where each spot corresponds to waves coming from a very specific source. The size of the specific source is the angular resolution of the mirror, which depends on how many wavelengths you can fit into the mirror. Because radio waves are so long, radio telescopes must be very large -- that's why you see big radio "dishes" many meters in diameter. Moreover, signals from many dishes are often combined to make the resolution even better. The long radio waves mean that the surface doesn't need to be perfect -- or even solid. A wire mesh design is very common. However, the long waves also mean that a radio telescope as large as the Earth would still not have the angular resolution of a backyard visible light telescope.