me
"Optical", in this case, simply means that they work with light.
Radio telescopes collect radio waves. Optical telescopes capture visible light waves.
An optical telescope collects and focuses visible light from celestial objects like stars, planets, and galaxies. This light is then directed to a detector or eyepiece for observation and analysis.
An optical telescope focuses and concentrates visible light; radio telescopes focus and concentrate electromagnetic radiation (which means, "light") in the radio part of the spectrum.
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.
As far as I know, there is no "optical radio telescope". There are, separately, optical telescopes (which work with visible light), and radio telescopes (which work with radio waves).
The surface of a radio telescope doesn't have to be as flawless as the surface of an optical telescope because the radio telescope is collecting radio waves, something that will not be affected by faults in the glass. Optical telescopes, on the other hand, are collecting light, where faults in the surface can interfere with the image.
Optical!!
A small aperture.
The Hubble Space Telescope has a number of instruments, but the primary one is an optical telescope.
Allows you to gather more light from a distant object.
A telescope ray diagram can be used to show how light rays enter and are focused by the lenses or mirrors in a telescope. This helps illustrate how the telescope magnifies distant objects and forms an image for the viewer to see. By analyzing the paths of the light rays in the diagram, one can understand how the optical principles of the telescope work to enhance our ability to observe objects in space.