What's the use of ultraviolet rays? Is it harmful to shine on human body?

Ultraviolet lamp is a device that can emit ultraviolet rays, is a necessary tool to observe the fluorescence and phosphorescence characteristics of samples, and is also a physical means of sterilization. The wavelength is in the range of 10~400nm.

The harm of ultraviolet rays to human body is mainly eyes and skin: keratitis, conjunctivitis and skin cancer.

But the degree of damage depends on the intensity of ultraviolet light. A weak lamp is either far enough or short enough to cause no harm.

Generally, this kind of ultraviolet lamp should be marked with safety instructions.