Reflector.
A small aperture.
camera ,microscope, telescope are some knids of optical instruments
The non-optical telescope, primarily radio telescopes, were invented in the 1930s. One of the first and most notable radio telescopes was built by Karl Guthe Jansky in 1931.
The Keck Observatory in Hawaii is a 10 meter optical telescope. Even larger is the Great Canary Telescope off the coast of Africa (west of Morocco) at 10.4 meters. EU scientists have requested permission to build a 40 meter optical telescope. The largest single radiotelescope dish is Arecibo.
That sounds like the description of a telescope. However, please note that the distance objects need not be "small"; a galaxy, for example, is incredibly large, but most galaxies are so far away that we can still not see them without the help of a telescope.
well,both telescopes let you look into the ground into the inner core and you see deep in he atmosphere which is space. Errr... The Very Large Array is an array of radio-telescopes, i.e. it detects radio emissions from stars and similar. An optical telescope as its name suggests, collects visible light. The similarity is that increasing the aperture increases the radiation-gathering power by a square-law. In an optical telescope this is achieved by a larger mirror (or lens but most large telescopes are reflecting.) The VLA uses a "synthetic aperture" to gain the advantages of increasing its gathering area without the cost and complexity of building a single, very large dish.
To most easily observe a neutron star, a powerful telescope with capabilities for high-energy astrophysics is required, such as a radio telescope or an X-ray observatory. Neutron stars emit primarily in the X-ray and radio wavelengths, so instruments like the Chandra X-ray Observatory or the Very Large Array (VLA) for radio astronomy would be ideal. Optical telescopes are generally not effective for observing neutron stars directly due to their faintness in visible light.
They are much shorter than refracting telescopes, hence, much cheaper to buy and easier to transport.
An Astronomer
Most optical devices are poorly waterproofed; I would not recommend it without keeping the telescope under an umbrella or in a protective casing.For astronomical use, of course, you won't see any stars through rainclouds....
Historically, it was the optical telescope. Modern radio telescopes, and cameras mounted on satellites, have advanced astronomy even further.
It is the one kind of telescope use in space. The Hubble Space telescope, is the one of the most common used-technology in space. The Hubble Space telescope was named after Edwin Hubble.