As you know, ultraviolet light is invisible light. It is essentially an electromagnetic wave And its application characteristics are based on wave-particle duality.
Therefore, whether it is the application of ultraviolet light or the development and design of ultraviolet flashlight products.
It is all based on the basics of optical characteristics.

For the volatility of ultraviolet light, it mainly describes the process of its propagation. It also applies to the three laws of light propagation:

The first reason being that ultraviolet rays travel in a straight line in a vacuum or the same homogeneous medium.
It reflects the characteristics of the direction of propagation. The most common problem is that when ultraviolet rays are used for disinfection.
It is difficult to have radiation dose at the corners. That is why the ozone produced by the mercury lamp is more effective in eliminating bacteria. https://www.tank007.com/product-category/uv-flashlight/

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