I work for a night vision company, let me answer it:
The first question: Ordinary infrared night vision just uses infrared lights and ordinary cameras. This kind of infrared night vision uses a circle of infrared lights to fill in the light, and then uses an ordinary camera to capture the picture. This so-called infrared is not infrared in the true sense. The principle is that an ordinary camera adds light to fill in the light. In night conditions, the monitoring effect is not ideal.
The real night vision device uses "infrared thermal imaging" technology. Because any object above absolute zero emits infrared rays, thermal imaging technology captures these infrared rays for imaging. Therefore, real infrared thermal imaging is passive, using the infrared rays emitted by the object to image, rather than using a light source to fill the image. Infrared thermal imaging has a specialized thermal imaging lens and detection core, which are fundamentally two completely different things from ordinary infrared light cameras. A true infrared thermal imaging night vision device can still clearly display the outline of an object in complete darkness and does not require any supplementary light measures.
Summary: The so-called infrared cameras currently on the market are ordinary cameras plus infrared lights. They are low-cost and the market price is naturally cheap. Professional infrared thermal imaging cameras use infrared rays to image based on the heat emitted, which requires the use of professional detection movements and professional thermal imaging lenses. This mainly relies on technology, and the product cost is high, but the actual application is more convenient. Ordinary infrared cameras cost around a few hundred. After all, this kind of machine only has one camera and a circle of LED lights. The price of real infrared thermal imaging ranges from tens to hundreds of thousands.
Second question: The so-called security monitoring is a small camera placed in a community or front room. Its main purpose is to monitor the flow of people. The main application time is during the day and a few hours after dark. The application environment is in a bright environment.
Real night vision devices are different. They are mainly used in railways, rivers, oil fields, highways, border defenses, coastal defenses, large reservoirs, forests, scenic spots, plains and other large-scale venues. It is mainly used to monitor the situation at night without supervision, that is, the situation that the human eye cannot observe.
Summary: The monitoring range of ordinary security cameras is only tens to hundreds of meters, while the monitoring range of real night vision devices can reach several kilometers or even ten kilometers. People in the market refer to the two types of night vision devices as "night vision monitoring", but essentially they have nothing in common.