Why are the large telescopes reflectors and not refractors?
Large lenses deform under their own weight, but mirrors can be supported. Reflectors do not suffer from chromatic aberration like refractors do. Large mirrors need only one optical surface, achromats four surfaces to grind.
Large, very clear lenses are harder to cast than more tolerant mirror blanks.
Both refracting and reflecting telescopes are used in astronomical observations. Reflectors are easier to build and are more compact that refractors, so most of the really large telescopes are reflectors.
Refractors (with lenses) Reflectors (with mirrors)
There are two basic types of telescopes, refractors and reflectors.
The two main kinds of Optical telescopes are refractors (dioptrics) and Newtonian reflectors (catoptrics) Refractors use lenses while reflectors use mirrors. Besides those, there are also catadioptric telescopes which use mirrors and lenses in combination.
There are two basic optical designs-- Refractors, which use solid glass lenses to focus the light, Reflectors, which use (mainly) reflecting mirrors to focus light. Many design variables determine whether refractors or reflectors are the best choice, but for very big astronomical telescopes, reflectors are always much cheaper.
Most large modern telescopes are reflectors, because a large refracting telescope is enormous and heavy. The primary telescope of the Lick Observatory near San Jose, California may be the largest refracting telescope.
Because large refractors mean large lenses, which are incredibly difficult to make. It's hard enough to make large mirrors, which is why the largest telescopes now use multiple smaller mirrors instead of one big one.
Basically, the larger the mirror (in reflectors) and the larger the lens (in refractors), the greater the light gathering capacity. Therefore you can see fainter stars. But there is a limit for refractors because the glass gets too heavy and starts to sag. The biggest refractor is 40" Yerkes Telescope and that is about the limit for refractors. But reflectors are supported behind or beneath so they can be huge.
Approximately none of them are.
Those two particular categories of equipment have essentially identical functionality and characteristics. I think the question meant to say "over refractors".
most large optical telescopes are reflectors; light does not pass through a mirror so the glass for reflecting telescope does not have to be of optical quality.
Reflecting telescopes give a brighter, clearer image that refraactors in many cases. Add to that the fact that refractors become very impractical with objective lens sizes much above 40 inches, while reflectors can have mirrors of 200 inches and more.
Large mirrors are easier to build than large lenses.
Astronomical telescopes used for viewing visible light may be divided into two general classes refractors and reflectors Describe the main components of each?
a refractor uses a lense, a reflector uses two mirrors, IS THAT SIMPLE ENOUGH?!
No, the largest telescopes are all reflectors.
Refractors - Refractors have a long, thin tube, and use a glass lens to gather and focus light. Refractors are sturdy, require little maintenance, and have sealed tubes to prevent dust or air from interfering with viewing. Larger refractors produce clear, high-contrast images, and smaller models are popular as starter telescopes because they're also inexpensive. Refractors can reveal details of the planets and the moon, even when viewing them under city lights. However, because refractors… Read More
The advent of the Dobsonian telescope has made refracting telescopes less popular because the large mirrors of the reflectors gather so much more light for the same amount of money.
Refractors and reflectors. One should add the largely Russian-developed Cassegrainean combines features of both systems-called also Maksutov after its Russian inventor who was awarded the Staliln Prize for this feat. They are adapted to (Mirror=Lens) telephoto camera lenses, also.
All of the large optical telescopes built during the past century have been reflectors. I live not too far from the 40-inch Alvan Clark refractor at Yerkes Observatory in Wisconsin. It was built in 1897 and it's the largest refractor used for scientific research.
A reflecting telescope uses the reflection of light as its method of focus. A refracting telescope uses the refraction (or bending) of light as its method of focus. Reflecting telescopes are much more useful than refracting telescopes, as chromatic aberration is not an issue, and have a significantly larger range than refractors. Nearly all observatories have reflectors in them, as they are much more practical.
None. He used the type of telescope that was available at the time, with a large convex object lens and a small concave eye lens. He made important discoveries and this type of telescope is now called a Galilean telescope. The Galielean telescope has a small field of view and provides magnification up to about 30x. This type of telescope is now only used in cheap children's telescopes and opera glasses. Astronomical telescopes, refractors and… Read More
Refractors use a concave lens to refract the light rays through the main body, off the rectangular prism and into the eyepiece. These telescopes use no mirrors like reflectors (except the triangular prism contains a small mirror but a triangular prism is optional)
We use telescopes because some things in the sky are too dim to see, and they enhance our vision. Types of telescopes (there are 3): 1. telescopes that use lenses 2. telescopes that use mirros 3. telescopes that use a combo of both. Telescopes that use lenses: -The lenses bend light. They are called refractors. -The main lens is its objective. -Each lens have what are called focal points (the distance from lens to where… Read More
Yes. Galileo's telescopes were refractors with a large object lens at the top end. The type of refractor is now called a 'Galiean' telescope in which the eye lens is a concave lens. This type of telescope is now only used in cheap telescopes and binoculars with low magnification. Modern refractors have an eye lens with one or more usually two convex lenses that provide an inverted image. A further pair of lenses can give… Read More
Telescopes can be broadly classified into two types: Optical Telescopes Non-Optical Telescopes Optical Telescopes Optical telescopes are those telescopes that are to used to observe electromagnetic radiation in the visible region of the electromagnetic spectrum. Most often, while using these telescopes, we see the image directly with our eyes. Some optical telescopes like the VLT (Very Large Telescope) or the Hubble Space Telescope take digital pictures of the images and store it. Optical telescopes are… Read More
Refracting telescopes, as opposed to reflectors, whose primary optical elements are mirrors.
All telescopes work best in the vacuum of space. Aside from that, "where" really is not a great factor compared to other types of telescopes. The distinct advantage of some reflecting telescopes is that they don't suffer from chromatic aberration like refractors do.
If you are asking: What do things look like in a telescope, then the answer is: upside down and reversed left to right. The two main kinds of telescopes are reflectors and refractors. And, unless there is an erecting prism in them, everything looks upside down. Binoculars are a pair of refracting telescopes mounted so you can see through both of them at the same time. The image you see is right side up because… Read More
I would qualify that as "most LARGE telescopes". Telescopes for home use can be of both types. (1) For a large telescope, there is a limit to how large the main lens can be before it collapses under its own weight. A mirror, on the other hand, can be supported on its bottom side - and it need not be as thick as the corresponding lens. (2) In a lens, two sides must be polished… Read More
Reflecting telescopes do this. There are many different kinds of reflectors.
Reflectors - the main two types being Newtonian and Cassegrainian.
The telescopes used by Leeuwenhoek, Huygens, and Galileo were refractors. Newton fashioned the first reflector, with a primary mirror of made polished brass.
Reflecting telescopes are the largest telescopes because it is easier to build large mirrors than large lenses.
Refracting telescopes put a very serious limitation on how large the telescope's aperture can be because they require a large area of unsupported glass.
A Dobsonian-mount telescope is the best for beginners. There are no complications with mounting it on stands or anything like that. But then, there are other choices. It depends from person-to-person. Some prefer Refractors, some prefer reflectors. I suggest that you join a local astronomy club as that will give you a better idea. You can look through a few telescopes and decide which you are most comfortable with and what fits in your budget… Read More
Telescopes come in many types and sizes, and some are very specialized for particular science projects. The most common types fall into two types: optical, and radio telescopes. Optical telescopes can be refractors, or lens type. The lens, like a hand magnifier lens, bends and focuses the light to a small, intense spot. Other lenses in the eyepiece enlarge the image to many times bigger than the unaided eye can see. These can range from… Read More
It all depends on if the telscope is a refractor, or a reflector. Reflectors have a convex mirror that bends the reflection on to a flat mirror that angles the magnified reflection to the eyepiece. Refractors use to convex lenses that bend the image and light, magnifying the view to the eypiece.
Ccd's and in large telescopes
They're not. When you compare a reflector and a refractor whose objective mirror and lens have the same diameter, the reflector is cheaper and easier to build. That's why, since 1895, when the 40-inch refractor was installed at the University of Chicago's Yerkes Observatory in Wisconsin, all larger telescopes have been reflectors.
A refractor has no obstacles in the image path which can cause diffraction. reflectors have "spiders" (newtonians) and/or multiple optical elements which result in diffraction and lower respective image quality. both types have their advantages and disadvantages. given any specific objective size, the refractor design is generally more expensive, and at a certain point (about 40"), refractors become infeasible due to the weight of the primary objective lens and the length of the tube. reflectors… Read More
That is because reflecting telescopes will have a greater magnification in a smaller space. Refracting telescopes that magnify to the same degree as reflecting telescopes would be much larger than the reflecting telescopes.
Large telescopes have improved resolution over small telescopes and as such can gather clearer images of objects further away.
Two large objective lenses.
A refracting or refractor telescope is a dioptric telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used in other devices such as binoculars and long or telephoto camera lenses. There are two basic types of telescopes, refractors and reflectors. The part of the telescope that gathers the light, called the objective, determines the type of… Read More
That depends on what you are looking at. Reflectors are great for looking at galaxies close up and are usually cheaper. Refractors are better for seeing color in objects, however some brightness is lost as a result of the two-way mirror the light has to pass through.
Dioptrics is the study of the refraction of light, especially by lenses. Telescopes that create their image with an objective that is a convex lens (refractors) are said to be "dioptric" telescopes. An early study of dioptrics was conducted by Ptolemy in relationship to the human eye as well as refraction in media such as water. Understanding of the principles of dioptrics was further expanded by Alhazen, considered as the father of modern optics.
Telescopes are not dangerous in normal operation. A large telescope might hurt you if it fell on you.
Refracting telescopes suffer from chromatic aberration, refracting telescopes have several surfaces to shape and polish, making large glass lenses without interior defects is very difficult, and large glass lenses are more difficult to support than large mirrors.
How is a telescope made? A telescope is a device used to form images of distant objects. The most familiar kind of telescope is an optical telescope, which uses a series of lens-1 or a curved mirror to focus visible light. An optical telescope which uses lenses is known as a refracting-telescope or a refractor; one which uses a mirror is known as a reflecting telescope or a reflector. Besides optical telescopes, astronomers also use… Read More
It is cheaper and easier to create mirrors rather than lenses. Large lenses become difficult to support the larger they become. Additionally, mirrored telescopes fold light waves so that a telescope can be shorter, the same size telescopes with lenses are greater in length.