What is a Cassegrain telescope?

Whether you’ve never looked through a telescope before or are a long-time appreciator of astronomy, a Cassegrain telescope has a lot to offer you. These unique optical items are most well known for their use of coaxial reflectors, which allows this scope to actually bend light, manipulating it in a manner that grants a crystal clear view of the world beyond.

Laurent Cassegrain is the man behind the design of this wonderful scope. All the way back in the seventeenth century, this great man stood on Newton’s shoulders and designed his scope based on the existing Newtonian design. He modified the classic Newtonian design to incorporate two mirrors located at the rear and front of the telescope. These mirrors are symmetrically positioned to actually bend light.

The rear mirror is a convex mirror which serves to gather the light. It then bounces that light up to the secondary convex mirror which has a hyperbolic shape to allow it to fold the light. This secondary convex mirror has a glass plate supporter. This glass plate supporter serves to prevent distortions or star-shaped diffractions. The light is then sent back to the primary mirror which has a parabolic shape. It is received through a small precise hole. The light enters this whole and is transmitted through the eyepiece, thus creating a crystal clear field of vision.

Because the light is folded or bent, this telescope does not require as long of a tube as some other models and types of telescopes do. This means that fewer materials are required in the manufacturing phases, which ultimately serves to cut down on manufacturing costs. This equates to a more affordable model of telescope, which is one of the reasons this model has become so widely popular among so many different levels of astronomers, appealing to both professionals and amateurs alike.

In addition, because the Cassegrain model of telescope bends light and makes use of a smaller tube, it boasts a more compact form. People of all skill levels enjoy this compact form for its ease of portability, allowing them to enjoy amazing views with a great flexibility in location.

However, if portability is not a concern of yours, then you may be interested in the non-compact form of the Cassegrain telescope. These do tend to be more expensive than the compact designs, but they typically offer improved aberration correction. You’ll also be able to enjoy a flatter field as well.