My site carries the ATN Night Binoculars, Night Goggles, and Night Monocular so I will be referring to our technology and how our equipment works.

In my previous article I mentioned briefly how night vision works. In this article I will go deeper in this area and give you a better understanding and explanation of how these devices help you see in the dark.

All Starlight technology Night Vision Devices consist of several main parts: an objective lens, an eyepiece, a power supply and an image intensifier tube (Photocathode Tube).Night vision devices gather existing ambient light (starlight, moonlight or infra-red light) through the front lens. This light, which is made up of photons goes into a photocathode tube that changes the photons to electrons.The electrons are then amplified to a much greater number through an electrical and chemical process. The electrons are then hurled against a phosphorus screen that changes the amplified electrons back into visible light that you see through the eyepiece. The image will now be a clear green- hued amplified re-creation of the scene you were observing.

A Night Vision Device can be either a 1st, 2nd, 3rd or 4th generation unit. What this stands for is what type of image intensifier tube is used for that particular device; the image intensifier tube is the heart and soul of an NVD.

1st generation is currently the most popular type of night vision in the world. Utilizing the basic principles described earlier. A 1st generation unit will amplify the existing light several thousand times letting you clearly see in the dark. These units provide a bright and sharp image at a low cost, which is perfect, whether you are boating, observing wildlife, or providing security for your home. You may notice the following when you are looking through a 1st Gen. unit.

• A slight high-pitched whine when the unit is on.

• The image you see may be slightly blurry around the edges. This is known as Geometric Distortion.

• When you turn a 1st Gen. unit off it may glow green for some time.

• These are inherent characteristics of a 1st Gen. unit and are normal.

2nd generation is primarily used by law enforcement or for professional applications. This is because the cost of a 2nd Gen. unit is approximately $500.00 to $1000.00 more than a 1st Gen. The main difference between a 1st and a 2nd generation unit is the addition of a micro-channel plate, commonly referred to as a MCP. The MCP works as an electron amplifier and is placed directly behind the photocathode. The MCP consists of millions of short parallel glass tubes. When the electrons pass through these short tubes, thousands more electrons are released. This extra process allows 2nd generation units to amplify the light many more times than 1st generation giving you a brighter and sharper image.

All Starlight scopes need some light to amplify. This means that if you were in complete darkness you could not see. Due to this we have a built in infra-red illuminator (IRI) on all of our scopes. Basically what an IRI does is throw out a beam of infra-red light that is near invisible to the eye but your NVD can see it. This allows you to use your scope even in total darkness. The IRI works like a flashlight and the distance you can see with it will be limited. We do use the most powerful eye-safe illuminator on the market. This allows our IRI to extend out to 100 yards. However, because of the power at a short distance the IRI may cover only 40-60% of the viewing area.

There are many different variables that can affect the distance you can see with a Night Vision device. First, what are you trying to see? Are you looking for another boat on the water or are you looking for a rabbit in the woods? The larger the object the easier it is to see. Plus, are you trying to see details (what we call recognition range) or are you just trying to see if something is there? Maybe you will just see the movement, but won’t be able to determine 100% who or what it is. This is called "detection range". A second variable is lighting conditions. The more ambient light you have (starlight, moonlight, and infrared light) the better and further you will be able to see. You can always see further on a night where the moon and stars are out, then if it is cloudy and overcast. We typically state that you can tell the difference between a male and a female or a dog and a deer at about 75 to 100 yards. However, if you were looking across an open field and there was a half moon out you could see a barn or a house 500 yards away. Remember that the purpose of an NVD is to see in the dark not necessarily at a long distance like a binocular.

I hope this article helps you understand what makes a Night Vision Device see in the dark.