How are reflector telescopes designed?

Reflector telescopes are designed in a different way than refracting telescopes are. these telescopes don't use lenses to focus light. Instead, reflecting telescopes have a highly polished glass mirror inside, and when a beam of light makes contact with this mirror, it is reflected.

Some reflective telescope history

Reflecting telescopes were invented around he year 1670 by the British scientist Sir Isaac Newton. He designed this new type of telescope, because refracting telescopes too error prone.

Because of the nature of lenses, they are susceptible to something called chromatic abberation. Chromatic abberation is something that happens in some refracting telescopes where the lenses break down over time.

What happens when a beam of light passes through a reflector telescope?

Reflecting telescopes have a mirror in them called the primary mirror. When a beam of light makes contact with the primary mirror, it gets reflected and this creates an image at what is called the focal plane. The distance from the primary mirror to the focal plane is called the focal length. The eyepiece in a reflecting telescope is located at the focal plane.

Typical reflecting telescope designs

Reflecting telescopes come in lots of different varieties. let's take a look at some of the more common designs:

  • Schmidt camera- The Schmidt camera was invented by Barnhard Schmidt. Since the light is captured with a photo lense, and not an eyepiece this device is considered a camera and not a telescope.
  • Newtonian focus- These telescopes are usually the simplest in design and the least expensive to buy. This kind of telescope is usually a good beginning telescope for amateurs.

So now you know the major differences between reflector telescopes and refractor telescopes. The main things to remember about reflecting telescopes are:

  • These telescopes use mirrors instead of lenses to focus the light.
  • These telescopes are less error prone than other types.

    By the way, if you're shopping for a reflecting telescope, this is the place to look

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