A Look Into The Inner Workings of Red Dot Sights

Chris G.

Picture a tiny, luminous dot guiding your aim flawlessly towards your target. That’s definitely the magic of a red dot sight. It’s effective, simple, and easy to use, making this firearm optic popular among shooters.

But what powers this pocket-sized wonder to achieve such accuracy? Let’s discuss the workings within red dot sights.

How Do Red Dot Sights Work?

Red dot sights are popular optical accessories used on firearms. Despite their outward sleek, high-tech aesthetics, they actually use a simple but effective operation.

  1. Light Emission: A typical red dot sight uses an LED (Light Emitting Diode) to generate and project a small illuminated dot onto a lens. The LED emits a specific wavelength of light, commonly in the red spectrum. This beam of light shows on the lens as a floating red dot, hence the optic’s name. The shooter uses the red dot as an aiming point.
  2. Lens Coating: The lens has a special coating to reflect only the specific wavelength—in this case, red—emitted by the LED. This coating helps to enhance the visibility of the red dot while reducing other colors and light interference.
  3. Parallax-Free Design: The special shape of the lens makes the sight parallax free. This means the reticle (red dot) appears on the target regardless of the shooter’s eye position.
  4. Reflex Sight Design: Most red dot sights are reflex sights. The reticle is projected onto a lens that reflects the image back to the shooter’s eye. The shooter superimposes the reticle on the target. With the right conditions and training, the bullet should hit the target.
  5. Battery Power: Red dot sights are powered by batteries that supply electricity to the LED. 

All other features and characteristics of a red dot sight revolve around this concept. Simple, right?

Parts of a Red Dot Sight

an image of a red dot lens

As an electronic optical device, a red dot sight typically consists of several essential parts. While red dots vary wildly in brand, model, and design, they share some general components. 

  1. Objective Lens: The objective lens, located at the front of the sight, allows external light to enter the sight.
  2. Coated Lens: The lens is coated to reduce glare, improve light transmission, and enhance contrast. Most importantly, the coating allows only the red light wavelength to be reflected; this creates the red dot reticle.
  3. LED (Light Emitting Diode): The LED is the light source that produces the red dot onto the sight’s lens. It is usually positioned inside the sight housing.
  4. Reflector or Parabolic Mirror: In reflex-style red dot sights, a reflector or parabolic mirror is used to bounce the LED-produced reticle image back to the shooter’s eye. 
  5. Reticle: The reticle is the resulting red dot that acts as an aiming point for the shooter. Red dot sights can have a simple dot, a dot with a surrounding circle, or other reticle patterns, depending on the sight model.
  6. Adjustment Turrets: Most red dot sights have adjustment turrets for windage (horizontal) and elevation (vertical). These turrets allow the shooter to zero the sight by aligning the point of impact with the reticle.
  7. Brightness Controls: Red dot sights often have controls for adjusting the brightness of the reticle. This can be manual in which the shooter adjusts the brightness with buttons or dials. Brightness adjustments can also be automatic where a sensor adjusts brightness based on ambient light conditions.
  8. Power Source Compartment: The power source compartment houses the battery or other power source that provides energy to the LED. 
  9. Electronics Compartment: Usually inaccessible, this compartment houses the optic’s electronic components and circuitry.  
  10. Housing/Body: The housing or body of the red dot sight protects the internal components from the elements and impacts. Usually, the body is made of durable materials like aircraft-grade aluminum, titanium, or strong steel to ensure the sight’s ruggedness.
  11. Mounting System: Red dot sights are mounted on firearms using specific mounting systems compatible with different types of rails (Picatinny, Weaver, etc.). The mounting system ensures a secure and stable attachment to the firearm.

Different Types of Red Dot Sights

There are various types of red dot sights in the market, each designed to cater to specific preferences, shooting scenarios, or firearm applications. 

  1. Tube Style Red Dot Sights: These sights have a cylindrical or tubular shape and are similar in appearance to a small telescope. 
  2. Open Reflex Red Dot Sights: Open reflex sights have an exposed lens that allows the user to look through the sight and see the reticle superimposed on the target. They are usually more compact and lightweight than tube-style sights, so they’re ideal for pistols and concealed carry handguns
  3. Holographic Sights: Holographic sights use a laser to project a holographic reticle onto a lens. They offer a more intricate and customizable reticle design compared to traditional red dot sights.
  4. Prism Sights: Prism sights use a prism to project the reticle onto the lens, allowing for a more compact design. They are often used on rifles and are known for their durability and etched reticles.
  5. Mini Red Dot Sights (MRDS): MRDS are compact and lightweight, designed for handguns, shotguns, or as secondary sights on rifles. They are often mounted on a pistol’s slide or on a dedicated handgun mount.

Applications of Red Dot Optics

a man aiming a hunting rifle

The versatility, speed, and ease of use make red dot sights popular firearms optics for a wide range of shooting applications. 

  1. Tactical and Home Defense Firearms: Red dot sights are popular choices for home defense firearms. They offer fast target acquisition and the ability to maintain situational awareness.
  2. Precision Shooting: Some shooters use red dot sights on precision rifles for close to medium-range shots. They can also be used in conjunction with magnifiers and traditional scopes.
  3. Law Enforcement and Military Applications: Red dot sights are widely adopted by law enforcement and military agencies for their effectiveness.
  4. Hunting: Hunters use red dot sights to improve target acquisition and shot placement, especially when hunting small and fast-moving game.
  5. Competitive Shooting: Red dot sights are popular in various shooting sports, including USPSA, IDPA, and 3-gun competitions. They offer speed and accuracy advantages, particularly in dynamic and fast-paced matches.
  6. Recreational Shooting: Whether at a shooting range or participating in recreational shooting activities, red dot sights can enhance the shooting experience for enthusiasts by simplifying target acquisition.
  7. Training and Skill Development: Red dot sights are valuable tools for training purposes, helping shooters improve their target acquisition speed and accuracy.


The technology that powers red dot sights makes these easy and even fun to use. It allows users to aim, track, and shoot targets with speed and precision. They’re a valuable tool for those serving in the police or military, shooters practicing on the range, hunters out in the wild, and anyone who handles firearms. Take advantage of the latest developments in red dot sights and improve your targeting skills.

About the author

The name's Chris. Just a regular dude who loves firearms. I've been shooting since I was a kid. My old man taught me the ropes.

I'll never forget the first time I missed an easy shot on a buck, thanks to a bum scope. The image was fuzzier than my dog's butt. After that, I got obsessed with understanding scopes. What makes the good ones tick and the bad ones trash. After a few years and a few thousand bucks, I learned what separates the winners from the losers. Once I had a good stockpile of knowledge, I launched this site.

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