Most security cameras typically use one of two night-vision systems: infrared and color. Infrared night vision devices have advantages over color night vision devices that utilize bright white light. For example, infrared LED lights provide a better range of lighting than colored night vision lights. As security professionals, we prefer cameras that are less visible, and invisible infrared light helps achieve that goal.
There are different types of night vision currently used and available within the market. These are not generational differences (i.e. Gen1, Gen2, Gen3) but technological differences such as Digital and Analog. All of these technologies are readily used and available in the security, hunting and camera markets. Most security cameras are using a digital system, as this is comprised of an internalized chip and sensor. Like most cameras you have the ability for a digital zoom enhancement. These digital systems can operate in both day and night, as there is no risk in damaging internalized components due to light exposure. Just like cameras, phones or recorders you can turn up or down the gain (sensitivity to light) control.
On the other end of the night vision market you have analog night vision. These devices are typically used in night vision binoculars, goggles or weapons sights, and are further evaluated by their Generational grade (Gen1, Gen2, Gen3). The main variance between the digital and analog system, is that analog uses magnified lenses (much like a traditional rifle scope) but with a photo-cathode image intensifier tube in the center of the magnified glass. These tubes gather all available ambient light, radiating a green image (green phosphorus tubes) or white/black (white phosphorus tubes) of the object or subject your viewing.