How do Telescopes Work?
All telescopes function basically the same way: they collect light and focus it to a point. An eyepiece is then used to magnify the image at the focal point and present it to the eye of the observer. Some telescopes use a curved glass lens to bend the light beams, causing them to converge at the focal point; others use curved mirrors. The diameter of a telescope’s main optical element (mirror or lens) is referred to as its aperture. Larger apertures collect more light, and therefore will produce brighter, sharper images. Aperture size is the most important factor in determining a telescope’s useful power.
