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Types of Telescope Lenses:
All telescope lenses are classified by the curvature of the two surfaces. The most common types of lenses are convergent and divergent. If the two are combined, the lens is called a convergent-divergent or meniscus lens. These are most commonly used in catadioptric telescopes. Some telescopes contain a combination of two or three lense styles called a doublet or a triplet.
Created By: Sam Villanueva
The lens on the left is a convergent lens, while the lens on the right is a divergent lens.
Refraction is shown in telescopes because they gather and focus light. Refraction is the changing direction of light as it passes through another medium. The objective lens in refractors collects light from a distant object and brings that light, or image, to a point or focus. An eyepiece lens takes the bright light from the focus of the objective lens and magnifies it to take up a large portion of the retina.
When you combine the objective lens or primary mirror with the eyepiece, you have a telescope. It collects light to form a bright image inside the telescope and uses something like a magnifying glass to magnify that bright image so that it takes up a lot of space on your retina.
This is a telescope that shows how the big lens gathers light at one end, directs it to a focal point, and the small lens brings the image to your eye.