How Do Reflecting Telescopes Work?

How Do Reflecting Telescopes Work?
••• NASA

Reflecting telescopes are generally built with two mirrors, a large one called the "primary mirror" and a small one called the "secondary mirror." The primary mirror is usually placed at one end of the telescope's tube, and the secondary mirror is placed in the eyepiece's line of sight. The eyepiece contains a magnifying lens.

A principle of reflection is that when light hits a mirror at any angle, it is reflected at that same angle. This means that the reflected image is not changed.

Depending on the type of reflecting telescope, the two mirrors can be a combination of concave, convex and flat mirrors. The secondary mirror, when flat, is placed at a 45-degree angle.

To obtain an image, the telescope is aimed at an object, and the light enters the tube. The light hits the primary mirror and is reflected to the secondary mirror. It is then reflected from the secondary mirror to the eyepiece, where the image is magnified and sent to the eye.

Related Articles

The Focal Length of Microscope Objectives
What Is the Difference Between Concave & Convex Mirrors?
How to Use a Refracting Telescope
How Do Bright Light Microscopes Work?
How to Determine Magnification of a Microscope
The Advantages and Disadvantages of Reflecting Telescopes
How to Find a Line of Reflection
What Is the Function of a Microscope?
How to Use the Bushnell Telescope 78-9512
Types of Spherical Mirrors
Test Your Knowledge on Middle School Science
What Astronomical Instrument Measures the Brightness...
How Does Telescope Size Affect Resolving Power?
How to Increase Resolution on Microscope
What Are the Uses of a Converging Lens?
Why is Quinine Fluorescent?
How to Measure a Magnification Mirror
How to Measure a Micron
Types of Microscopes Used in Biology