Light Gun Tech - Old & New
Published: 2022-12-19 12:45:53

I often recall how much fun I had playing video games as a kid. Most of the time I would just be amazed at how these games were working. One accessory for video games that always baffled me was the light gun. I had no idea how when I pointed the gun at the screen, did the game know where I was pointing. Recently, I decided to finally look into how this light gun technology worked.

## Early Video Game Light Guns

One of the earliest video game light gun was created for the Nintendo Entertainment System and called the Nintendo Zapper. The light gun was mainly made of plastic and had a cord which plugged directly into the game console. Inside the light gun, there are not as many parts as you would think. The device was mostly hollow, with two small weights inside to give the gun balance and a heavier feel. It also had a small circular clear lens at the end of the barrel and a photo sensor near the rear of the barrel.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/gzhfpnr9br9f4wlniwlb.png)

## How They Work

Before I tell you how they work, I feel it's important to tell you a little bit about another crucial part of using the light gun, the television in which you need to use the gun. In particular, I'm talking about the older CRT televisions. Without going to deep into how these tv's work, I will just say that if you are watching the screen, let's think of how an image is put on the screen. Imagine a small pixel or beam of light being put on the screen from the left side and sent to the right side of the screen. Now it moves so fast that our eyes can't see this process, but it keeps going until the image is rendered.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/9qwelaovk4phcvddv67t.png)



The Zapper light gun had a trigger, that when pressed, tell the game to to make the entire screen to turn black for just one frame. On the very next frame, the spot on the screen where the targets that you would shoot would be represented by a white box, however the rest of the screen would remain black. The photo sensor in the light gun then tries to detect the change in light levels to find the light. If you pointed at the light, the game registers a hit on that target. Keep in mind this happens so fast, it's nearly impossible to catch the process. All you are able to recognize is the the screen flash when you press the trigger.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/qd8neziu4oou1lm221k8.png)



![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/q8hs4q68nq0z9vcxjsl4.png)



## Why Don't They Work Anymore

The advancement of televisions meant no more CRT televisions. The way that light guns worked, heavily depended on the speed at which the pixels were lit up. Newer televisions worked a little different than CRT's and had a bigger delay which would mess up the timing of using the light gun.

## New Light Guns

Recently there have been a few companies who have created new light guns that would work differently than the older ones, in order to make them compatible with new televisions. They don't all work the same way, but I will mention two specifically. The first light gun called the Gun4IR, uses four sets of IR LED's which are strategically placed on the center of all four sides of your television or monitor. These IR LED's are used to help locate the positioning of where the light gun is pointed at the screen.

The second new light gun has a camera built in the gun instead of the normal photo sensor. This light gun was created by a company called Sinden and was introduced into the market not too long ago. This light gun requires a little more work to get the system going. The light gun is plugged into a computer which connects to your television. You must create a border on the television through your settings which let's the gun know where the playing field is located. Now because the light gun uses a camera, the lighting in the room you are playing could cause issues, especially if you are using bright LED lights.

## Final Thoughts

With the quickly changing advancements in technology for televisions, I am glad that there are companies out there trying to bring great gaming technology up to the forefront.

## Sources

youtube.com/watch?v=NuHoj4EljU
youtube.com/watch?v=hfo004_4xwU
youtube.com/watch?v=DzlPGpKo3Ag