All types of lens that see parts of the electromagnetic spectrum other than light. E.g. infrared cameras
reflecting telescopes
they use space probes,satellites,and of coarse,telescopes.
Telescopes made no contribution whatsoever to any society in the Middle Ages,mainly because there were no telescopes during the Middle Ages.
By using robot space probes and telescopes
Galileo perfected the telescope. So it was sometime before him.
Examples of scientific instruments include microscopes, spectrophotometers, telescopes, mass spectrometers, and DNA sequencers.
If you asking where you'd find them in the real world - Binoculars and telescopes are two examples.
Researchers use all of these: -- optical telescopes -- radio telescopes -- x-ray telescopes -- infra-red telescopes -- ultraviolet telescopes
Optical measures visible light, Radio measures electromagnetic radiation in that part of the spectrum corresponding to radio waves. Same with X-ray telescopes and x-rays. Optical is the kind you look through.
There are several instruments that are used to enhance visibility. Examples are; Spectacles and contact lenses Telescopes Microscopes
The Hubble Space Telescope (HST) is an example of an optical telescope, as are the Keck Observatory on Mauna Kea, Hawaii. the Hale Telescope at the Palomar Observatory in California and the Hooker 100 inch Telescope at the Mt Wilson Observatory, also California.
refracting
No they are not bigger then radio telescopes at all.
Radio telescopes collect radio waves. Optical telescopes capture visible light waves.
Ground-based telescopes, and space telescopes. Or: refracting telescopes (main collector is a lens), and reflecting telescopes (main collector is a mirror). Or: Home telescopes (small ones), and professional ones (larger and more expensive).
At a store for telescopes!
All space telescopes are unmanned - unless you want to count the small telescopes on the Shuttle or IIS as space telescopes.