Home » Gun Scopes » Tips & Tutorials » What is a Reflex Sight? | All You Need to Know

What is a Reflex Sight? | All You Need to Know

This post contains affiliate links. If you click and buy we may make a commission, at no additional charge to you. Please see our disclosure policy for more details.

Scopes/sights are vital pieces of accessories every frequent shooter should have. In fact, even though you’re not a regular shooter, if you value effectiveness and ease, getting a fitting scope/sight is paramount. Shooters understand it, and this has led to a boom in the optics industry with so many different optics types.

Different optics types can be overwhelming for the average user, which may stall its adaptation. Scopes are the most popular among them as most shooters have either used or seen them in action. Reflex sight, on the other hand, is not so popular. However, it is excellent for some shooting scenarios, which is why it is essential to know what reflex sights are and everything about them.

This article seeks to bridge the knowledge gap in the reflex sight niche and help shooters understand everything about it. Before we go ahead, we have to ask what a reflex sight is.

What is a Reflex Sight?

What is a Reflex Sight

A reflex sight is an optic that allows the user to look through a glass only partially reflecting and see an image of the target and the field of view superimposed. Typically, you look through a lens or curved mirror; your mark will appear in front at infinity. Reflex sight employs this principle, plus using a reflector to superimpose the field of view. This way, you not only see the target but the field of view in the same image.

A reflex or reflector sight is sometimes called red dot sight. So what is this all about? Are they the same? Yes and no. Hear me out, first. A reflex sight is a type of red dot sight and, as such, is a red dot. This means all reflex sights are red dots, but not all red dots are reflex sights.

In a reflex sight, most of the parallax is removed alongside other coming sighting problems because the reticle is in alignment at infinity and will remain in this position with the device no matter the eye position.

A reflex sight light source can be opened or closed. When the sight’s light source is open, it is also open to the elements, and things like dust, rain, fog, snow can obstruct the light and make it difficult to see through. A closed light source, on the other hand, is enclosed in the sight’s box and, as such, protected from the elements. You can use this type in any weather condition without a drop in quality.

History of Reflex Sights

Telescope manufacturer, Howard Grubb, filed the patent for his new invention, the reflex sight, in 1900 with patent no: 12108. By 1918, it got its first military use by the air force, which showed progress. This progress grew even further as it was used in several formations during the second world war.

Everything was going fine until a significant problem stalled its progress. The lack of small lighting elements to power the sight threatened the project.

By the 1970s, famous Swedish optics manufacturer Aimpoint achieved the much-awaited breakthrough by using the light of an LED as a light source for the reflex sight. This signified the new trajectory of the reflex sight as it has continued to grow in popularity as even more modifications take place.

How Does a Reflex Sight Work?

How Does a Reflex Sight Work

For a reflex sight to work, a small LED will create a colored point of light. This light is reflected off a small but semi-transparent mirror and returned to the front of the lens, showing like a luminous target. The semi-transparent mirror reflects part of the light, which is why you can see a clear image of the reflected point and the target when you look through.

Because of where the light beam is generated from – from the direction of the sighting line, the point will always appear to be in line, no matter where you put your eyes relative to the device.

A reflex sight is used with both eyes open. No matter your dominant eye, leaving the other eye open will allow you to see clearly. This is where it gets a little confusing as people who have been using scopes are used to closing their non-dominant eyes when looking through the sight. If this is the case, it may take you some time to get used to it.

How to Use a Reflex Sight?

Yes, you know what a reflex sight is and the working principle behind it. The next step is knowing how to use it to achieve the desired results. Luckily, reflex sights are user-oriented. They are easy to operate, and a newbie can easily understand how to use them in a short time.

The answer to how to use a reflex sight is pretty straightforward: the best way to use a reflex sight is with your two eyes open. This may sound easy, but it can become a challenge for people who have been using a scope for a long time and are used to using only one eye. People who are right-handed with left dominant eyes will also need some getting used to this sight.

If you’re not comfortable using the sight with both eyes open, you can practice by covering the exit lens with tape. This is because it is easy to spot this light on a dark background. After looking at this image for a while, if you take off the tape, you’ll notice you can see the red dot in brighter scenes.

Advantages of Using a Reflex Sight

Advantages of Using a Reflex Sight

There are so many advantages to using a reflex sight. If you’re not sure if this is the right choice for you, this section may be what you need to make a decision.

#1. Compact Build

A reflex sight is typically smaller, lightweight, and handy, which is great as the many accessories are already overwhelming—getting a sight that will not significantly increase the weight of your backpack or rifle when in use is vital.

#2. Fast Target Acquisition

Perhaps the most prominent advantage the reflex sight has over other sight is its fast target acquisition system. This system works as you do not need to align the front sight, rear sight, and target as in other optics. Only the luminous sight and target need aligning. You can lock in your target and shoot in record time and take your shot without wasting valuable time. Time is essential when shooting moving targets, so every second counts.

#3. No Tunnel Vision

Because it is used with both eyes open, tunnel vision is eliminated, and target acquisition speed is improved even further.

#4. Improved Accuracy

The accuracy of a reflex sight is never in doubt. It is one of the most accurate optics in short-distance shooting, typically under 50 meters.

Bonus Read: Why is My Rifle Scope Blurry? [Top Reasons & Quick Solutions]



Here are some of the cons to using reflex sights.

#1. Limited Range

The range of use of a reflex sight is limited to only short to medium distances. The maximum shooting distance to get the optimum accuracy from the sight is 50 m. However, you can aim at targets up to 150 m far. This limited distance may be a turn-off for people looking to do longer distances.

#2. Red Dot Luminosity at Night

At night, the red dot’s luminosity is severely affected, which may cause the target to overlap. You need to watch out for the brightness setting.

Also Read: Vortex Venom VS Trijicon RMR | Latest Comparison in 2022

Buying Guide

Buying GuideBuying Guide

If you want to buy a reflex sight, it would be best if you first considered some factors that are important for these types of sights. These factors act as guides to help you choose the right reflex sight for your needs.


You have the choice of choosing between open light source reflex sight and closed light source reflex sight. These sights are based on the housing structure used. An open light source sight has the light source outside the housing and, as such, is easily affected by the elements which can affect vision.

Closed light source sights, on the other hand, have their light source enclosed in the sight’s housing and are protected from the elements. This enables it to be used effectively in any weather condition.


The battery attached powers the LED light source and is a vital piece of equipment in the reflex sight. You have to consider this part when buying a reflex sight so you know how long you can use the rifle at a particular brightness setting before it runs down.

Manufacturers will typically provide the information on the number of hours you can use the sight at a brightness netting before it runs out. It would be best if you also considered sights with auto-shutdown capabilities to conserve battery.

Ease of Adjustment

It would help if you always considered the ease of getting your adjustments right. While most sights come with elevation and windage adjustments, not many can boast of an easy-to-adjust turret. Consider turrets with audible, tactile feedback so you can quickly make adjustments. You should also look out for reflex sight adjustments that can hold zero well.


The durability of any sight is essential. Getting a reflex sight that can withstand a lot of pressure without breaking down is paramount for you to enjoy your sight and save cost. Check the material used in constructing the piece and how it is made. Is it appropriately sealed? Is it a single piece body? These are some of the questions you can ask.


There are so many sights available, but a reflex sight stands out regarding the accuracy and speed of target acquisition. If any of these is crucial to you, you might find the reflex sight quite interesting.

You May Also Like: Thermal Scope vs Night Vision: What’s The Difference?

About Author

James Towndrow, a NRA-certified Firearms Instructor. During a career of 18 years had won several shooting competition including major leagues. Taking all those experience down the road, is now a successful Shooting Instructor in Texas, US.