Which type of telescope relies on mirrors rather than lenses to collect light?

• A. Eyepiece
• B. Microscope
• C. Reflecting telescope
• D. Electron microscope

Answer: (C)

Light gathering and focusing with mirrors is what defines this type of instrument. A reflecting telescope uses a curved mirror to collect incoming light and reflect it to a focal point. Often a secondary mirror redirects that light to an eyepiece or camera, so you see a sharp image without relying on lenses to bend the light. This mirror-based design lets astronomers build larger apertures more affordably and with fewer optical issues, such as chromatic aberration, which can blur colors in lens-based systems. In contrast, instruments that use lenses to bend light (refractors) face practical limits in size and can suffer from color fringes unless carefully corrected.

The other options aren’t about collecting distant light in the same way. An eyepiece is just a magnifying component at the end of the optical path. A microscope is built to magnify small, nearby objects and often uses very different optics. An electron microscope images with electrons, not light, involving a different imaging approach altogether.