The telescope is a fantastic instrument for Astro-research, astrophotography of the universe, and amateur astronomy lovers. A few decades ago, people did not know about the universe. Because telescopes were out of reach of the available people, researchers used them for researching space.

But nowadays, telescopes are smaller in size and affordable for the mass people. A telescope can collect light from the farthest object and magnify the image; thus, we can see it closer. Now the question comes – how do the Telescopes work? This article will explain each part of a telescope’s significance and how these parts work together to make a perfect image of the objects.

Significant Parts and Their Roles

There are several parts to a telescope. Sometimes, you get the separated parts, and you need to assemble them, or you can get a reassembled telescope; you need to set it up and adjust the focus. Now we will give you a top full idea about these parts:

    Aperture/Objective lens/Primary lensA telescope allows you to see the farthest object that can’t be seen with your bare eyes. To do that, a telescope must collect light/electromagnetic radiation from those objects. An aperture or primary lens does this task for a telescope. The bigger your aperture/primary mirror, the more light it collects from the objects. As the bigger aperture can collect more light, you should choose the more significant gap.
Magnification PowerYou know that a telescope gives you a closer & detailed look at the farthest objects, and this zooming depends on the magnification power. You may hear about the eyepiece. The eyepiece magnifies the distance of the image. The magnification depends on the eyepiece.
  Focal PointThe focal point is the main point of your focuser. The eyepiece needs to be at the focal point to focus correctly. A good focus is always important to get a clear and still image.
    EyepieceThat’s called an eyepiece because the eyepiece is the closest part of the telescope to your eyes when you see through a telescope. It is the nearest part to the focal point. It helps to magnify the objects. You can get the magnification power by dividing the telescope’s focal length by the eyepiece focal length.
    Focal tubeThis tube holds the parts of the telescope. The optical elements of a telescope are placed inside the line. It keeps the optical parts safe from physical damage. The eyepiece, finder scope, and lenses/ mirrors are all attached to it.
        MountTo set up your telescope, you need support or a stand. This stand is called a Mount. A Telescope mount is essential for stability and good focusing. There are mainly two types of telescope mount: The Equatorial mount and the Altazimuth mount.
The equatorial mounts are the computerized mount, and the Altazimuth mount is the manual version of the support. But manual and automatics don’t matter; first, you must ensure stability by ensuring the mount is strong enough.
  Finder ScopeTo observe any objects, primarily, you need to find the object. In a telescope, there is a finder scope by which you can find the objects.
FocuserThe focuser helps you focus on the object’s center; thus, you can get a clearer and more detailed image.

How Do Telescopes Work?

Generally, people use an optical telescope for astronomy or astrophotography. There are three modern optical telescopes; the telescope, the Refractor telescope, the Reflector telescope, and the Catadioptric telescope. The mechanisms are also different in these types. They work in various methods. Now we will explain the working procedure of each type one by one:

How Do the Reflecting Telescopes work?

A reflecting telescope is also called a Newtonian telescope. This type is different from other types because it uses a big concave curved mirror at the lens’s place. This concave mirror is placed at the back of the focal tube, and the line is not like another telescope tube; it is open. 

Primarily, you have to find the object you want to observe by a finder scope and focus it accurately. The big mirror/larger aperture at the back collects the light from the objects to produce brighter images. (Infographic)

The primary mirror then reflects the light to the secondary mirror; finally, it turns the eyepiece. The eyepiece magnifies the objects; thus, you can see the image in front of your eyes. (Infographic)

Subsequently, the image of the object comes from the detector or CCD. You can observe the beautiful night sky and the deep sky objects with a reflector telescope. (Infographic)

How Do the Refracting telescopes work?

A Refracting telescope has a longer tube than a reflecting telescope. It contains two lenses; one is a primary lens, and the other is a secondary one. Both of the lenses are Convex shaped. 

The object-finding and focusing processes are quite the same. But this process is straightforward. The primary lens is at the front. After collecting the objects’ lights by the primary lens, the light directly goes to the secondary lens through the long thin tube. 

Then it goes to the eyepiece, and the eyepiece magnifies the objects. Finally, we see the objects in the detector. 

The refractor telescope is easier to use than the reflector telescope. They’re suitable for observing celestial objects like the moon and the planets in the night sky.

How Does the Catadioptric Telescope work?

How Does the Catadioptric Telescope work

The Catadioptric telescope is a kind of compound telescope. Previously, we have seen that the refractor telescope uses a lens, and the reflector uses the mirror as an optical element. Interestingly, the Catadioptric telescope uses both mirror and lens as optical elements. 

Another surprising fact is that the light first comes to the secondary lens, and crossing the secondary lens, the light comes to the primary mirror. 

Conversely, in other Telescopes, the light first comes from the primary lens or mirror. 

Moreover, the object finding, focusing, and looking processes are quite the same for every telescope. 

Final Words:

That is how a telescope works. However, there are various telescopes. We have tried to give you an idea of the most commonly used telescopes. The works are similar for every telescope, but the working process differs. To summarize, a Reflector telescope uses a concave mirror to collect the light, and the eyepiece magnifies the distant objects.

The refractor telescope uses a lens to collect the light, and the process is relatively straightforward through a thin long focal tube. Finally, compound one – the Catadioptric telescope- uses a mirror and a lens.

The significant change is the light comes through the secondary lens to the primary mirror; contrariwise, the light first enters from the primary mirror/lens for the other two types. Magnification processes are the same for every telescope. That’s all. Thank you.


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