If you’re in the market for binoculars, you probably fall into one of two camps. You may be wondering how they work so you can make a better purchasing decision. Or you may believe choosing binoculars is a simple process and you don’t care how they work. After all, you can walk into any sporting goods store or hunting outlet and buy a decent pair right off the shelf. Whether you are looking for a good pair of binoculars for bird watching or for gazing at the stars, there is something for everyone.
In truth, however, to make the better decision on what type of binoculars are appropriate for you and not be disappointed, it will help to have a basic understand how the best binoculars work. In this way, you can ensure you’re not confused by all the technical data available to you and can use the information you’ve learned to make an educated decision.
Binoculars, also known as binocular telescopes, mainly consist of two identical telescopes mounted side-by-side with a center focus wheel positioned between them. The beauty of this design is that it allows you to form a complete and accurate multi-dimensional image of what you’re viewing, rather than the two-dimensional image you’re used to seeing through a typical telescope where you must close one eye and use the other eye to see the object.
So, how do binoculars work? It’s very simple. Each “telescope”, or tube, of the binocular, consists of several different components. These components vary, depending on whether you’re using prism binoculars or field glasses, but two elements all binoculars have in common are the objective lens and the eyepiece. At the front of each tube (nearest the object you’re viewing) is either an objective lens or a field lens. The purpose of this lens is to gather light from whatever image it is that you are viewing and then magnify that picture.
If you’re using prism binoculars, which are the most traditional kind, an erecting prism in each tube inverts (or corrects) the image you’re viewing.It reflects back instead. In field glasses, there’s a second lens instead of a prism. After the image has been corrected, the light then travels down the tube and through the eyepiece lens, where you see the image magnified even further. Binoculars with excellent lenses will provide you with a very detailed look at the object.
Though the components of the modern day binocular, such as the optics, are made of elements that have changed over the years, the basic construction of binoculars and how they work has remained unchanged for more than a century.
All still contain these three components. An objective lens which collects and focuses the initial image, a sets of prisms which inverts the image turning side up, and an eye piece that magnifies it. So, now that you know more about how binoculars work, you can more quickly decide what type of binoculars are right for you.