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How Does a Monocular Work? – A Detailed Explanation

how does a monocular work
Written by Marc Niad
Last Update: January 5, 2023

One tube, one lens, handheld (by one hand), and one EYEPIECE (to look through)! These describe what monocular devices are and how people use them. A monocular is a special telescope variant (typically smaller in size) modified with converging lens and crafted to magnify distant objects. The compact and lightweight design are what makes a monocular more preferable to many hunters and birdwatchers. If you’ve ever wondered about how does a monocular works, you are in the right place. This article will explore how monoculars work so if you really want to know, come along!

With this in mind, I feel some more details would be useful to you. So, here it goes.

Converging lens of monocular

How Does a Monocular Work

Sometimes, even the most experienced optics users can’t decide very comfortably when it comes to choosing between a night vision monocular, monocular and binoculars. It’s not surprising because all of these are optical devices with a marginal difference in function. So, their significantly dissimilar looks matter little when you’re serious about ‘utilities’. The only way to overcome the confusion and rest assured that a high-spec monocular is all you needed is knowing the functional explanation of a monocular.

Some people ignore this part thinking that it won’t do them any good. But I don’t buy it, and I believe you don’t either since you’re still on this page reading this article! So, here’s how a monocular device works.

1. How Does a Monocular Magnify Distant Objects?

A monocular passes light through prism lenses and magnify the objects/targets to make the distant vision clear. Prism may work as a therapeutic lens that assists one’s brain to turn the eye (the one you use and is more powerful than the other) in the right direction.

dispersion of light through prism

In terms of light refraction, prism lenses are unlike typical optical lenses. Consequently, these lenses impact your sight and vision differently. For example, a prism consists of a pointed top and a base resembling the shape of a pyramid. Every time light passes through, the lens bends it towards the base, the object (visible through the prism) typically moves toward the pointed top. Thus, the visible object/target apparently moves in that direction.
hoose a monocular over binFocus Monocular

Prism lenses, if used in variable orientations and magnification power, impact the direction of our sight. Ultimately, we get a single vision instead of a double.

2. Why Does Lens Size Matter?

If I told a monocular is a lightweight device (without much explanation), that would make you wonder why even a monocular is being talked about where compact binoculars are also lightweight, if not equally, with bigger potentials. Well, here’s a cue, “the lens size has something to do with the weight of your monocular”.

The typical size of a monocular lens runs anywhere between 20mm and 42mm. Sizes on the higher side should allow for a better, brighter, and even wider view. But they aren’t equally forgiving when it comes to the weight of the device. Bigger lens sizes add to the device making it a bulky, heavy unit.

How Do Different Sizes Work?

Although devices with typical lens sizes yield adequate power for many people, you would want bigger lenses to overcome the drawback (limited view). A monocular that has a size anywhere between 30 mm to 42mm should be enough for most people as they need a brighter and wider view of the distant object.

Typical lens size of monocular

3. The Uses of Monoculars

Let me ask you a question. Do you have a monocular vision? Are you one of those smart, lightweight backpackers/hikers who accept no less than a lightweight optical device? A monocular with a smaller lens size and compact body should be the right fit. It’s not your fault if your eyes, after being put through the lenses, don’t see things equally. Finding a perfect monocular may help you handle these difficulties and makes you forget the grief of having a one-eyed, impaired vision.

A monocular proves useful in situations when you don’t want to tout your presence and scare away the unsuspecting targets. You can keep things almost unnoticed giving a sneaky look at the object. Also, these devices are great for single-handed uses.

A monocular allows users to obtain distant vision in a variety of circumstances like sightseeing, military activities, birdwatching, bird hunting, archery, fishing, mountaineering, hiking, and many other outdoor pursuits. Most of these occasions would demand higher magnification, better resolution, and brighter images of distant targets/objects, and thus larger devices. Since monoculars don’t have built-in LEDs like the hunting flashlights, we’d recommend using them while the sun is still up.

4. Monocular Vs Binocular: Which Works Better?

No doubt that all these are highly engineered optical gadgets! Some make mistakes by considering monocular devices to be alternative to either binoculars or spotting scopes. But, in practice, a monocular has its uses while the other devices have theirs.

Needless to say, binoculars and spotting scopes are better when your game involves seriousness rather than mere observation. A monocular is the best way to satisfy your needs for distance vision just when you don’t want to keep both of your eyes and hands busy (a typical case with binoculars) or add some more weight to your traveling arrangement (by carrying a tripod to stabilize a spotting scope).

By now, I’ve tried to explain “how does monocular work?” in details and what makes it different from other devices that are in use. Got more questions on the topic? Well, I’m not tired. Shoot me anything that comes to your mind!

About the author

Marc Niad

It’s been several years that Marc, a retired teacher and a proud dad, has silently been piling up mature bucks down the South. This humble hunter began his hunting journey at quite an early age and since then, he spent countless hours in the woods and learned good lessons in terms of woodsmanship. Along the way, he also made money sharing his skill with his followers and well-wishers.

The Ranger Expert is the brainchild of this veteran hunter who loves hunting the swamps and the hills around the Mississippi and Homochitto rivers. His most favorite hunting technique is taking his climbing gear and going to the top of pines with a 25.06 – the old-fashioned way!

He gets most of his games during late December through mid-January – his favorite hunting time. Marc strongly believes that hard work, passion, and a bit of luck can bring you success in the wild.

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