A reflecting telescope should have a parabolic mirror in which case there is no spherical aberration. The process of turning a spherical mirror surface into a parabolic one is called 'figuring'.
A reflecting telescope has both magnifying mirrors and lenses to focus the image on the eyepiece. A refracting telescope uses only lenses to magnify and focus. A reflecting telescope can be much smaller, because the light can travel through the barrel of the telescope several times, being magnified with each reflection. This is why most large modern telescopes are reflectors.
A reflecting telescope only uses lenses in the eyepiece. Light is picked up and an image produced by using a concave parabolic mirror.
An optical telescope (as distinct from, say, a radio telescope). It's possible that the answer was intended to be "a refracting telescope" but reflecting telescopes use lenses as well.
Gathering and focusing light from distant objects.
The name of this type of instrument is derived from the fact that the primary mirror reflects the light back to a focus instead of refracting it. The primary mirror usually has a concave spherical or parabolic shape, and, as it reflects the light, it inverts the image at the focal plane.
A reflecting telescope uses mirrors while refracting telescopes uses lens. The refracting telescope also had chromatic aberration and bad resolution while the reflecting telescope had none of these.
Spherical aberration in a telescope occurs when light rays do not converge to a single point, resulting in a blurred or distorted image. This can happen due to imperfections in the shape of the telescope's primary mirror or lens. Correcting for spherical aberration is important for achieving sharp and clear images in telescopes.
A reflecting telescope uses mirrors while refracting telescopes uses lens. The refracting telescope also had chromatic aberration and bad resolution while the reflecting telescope had none of these.
A reflecting telescope gathers light with a mirror instead of a lens. The mirror reflects light to a focus point where the image is formed. This design eliminates chromatic aberration that can occur with lenses.
There's no aberration with the main MIRROR of the telescope, because light doesn't go through the mirror. A reflecting telescope will have SOME chromatic aberration, because every reflecting telescope has at least one refracting lens; the eyepiece. Light goes THROUGH that lens, and light passing through the glass lens will generate some chromatic aberration.
A reflecting telescope has both magnifying mirrors and lenses to focus the image on the eyepiece. A refracting telescope uses only lenses to magnify and focus. A reflecting telescope can be much smaller, because the light can travel through the barrel of the telescope several times, being magnified with each reflection. This is why most large modern telescopes are reflectors.
There were many inventors that had ideas and even drawn out ideas on building a telescopes that used mirrors instead of lenses, but here are a few:Galileo, Giovanni, and Francesco Sagredo (with others, talked about this idea)Cesare Caravaggi (reported to have built one)Niccolò Zucchi (again reported to have built one)James Gregory (most notable, but had no working models)Robert Hooke (built a working model)Isaac Newton (generally credited with constructing the first practical reflecting telescope)Hence, most would credit Isaac Newton for building the first practical reflecting telescope.
a cheap refracting telescope with a simple lens system. Chromatic aberration occurs when different colors of light focus at different points, and low light-gathering power could be due to a smaller aperture size.
A parabolic mirror, usually. A spherical mirror is also sometimes used, but that requires additional corrections in other parts of the telescope.
== == Newton did not invent the reflecting telescope. The first reflecting telescope is credited to Niccolò Zucchi in 1616. In 1668, Isaac Newton made significant improvements to the design resulting in a much improved reflecting telescope that still bears his name, the "Newtonian reflector." He did it because the refracting (lens) telescopes of the day suffered severe color aberration. (Different focal lengths of different colours of light resulting in a blurred image because all the colours can't be brought into focus at the same time.) Reflecting telescopes do not suffer from color aberation and Newton's improvements made them effective observing instruments. Although the colour aberration of refractors was partially solved by the invention of the achromatic lens in 1733 Newton's design remains in use to this day.
Isaac Newton improved the first refracting telescope by designing a reflecting telescope, known as the Newtonian telescope. He replaced the eyepiece of the refracting telescope with a curved mirror to eliminate chromatic aberration, resulting in a sharper image with less distortion. This design laid the foundation for future advancements in telescope technology.
Isaac Newton invented the reflecting telescope.