Laser flashlights can only be used where necessary in life. From this point of view, the laser energy is not very large. But its energy density is great. Because its scope of action is very small, there is generally only one point. A large amount of energy is gathered in a short time, and it can be understood as a weapon. It is self-evident how powerful it has. The high-power laser pointer are all above 10 milliwatts. The laser flashlights sold online have basically reached 250 milliwatts. Obviously, they have caused the above three to four levels of damage. Specifically, when the laser light emitted by the laser flashlight reaches the sensitive part of the human retina, it will cause damage to the eyes. In addition, after looking at the dazzling beam for a long time. It can also affect the optic nerve and central nervous system, causing dizziness and even nausea. Therefore, never use a laser beam to illuminate another person's face or eyes. Nor can mirrors and other objects reflect laser light.
The output power of a standard laser pointer is less than 0.4 milliwatts. This is because the laser of this energy is directed to the eyes and skin under any conditions. Will not cause damage. Even after focusing through the optical system, it will not cause harm to the human body, so this type of laser product is a type that does not need special management. The laser output power of the secondary standard is between 0.4 milliwatts and 1 milliwatt, and the response time for people to close their eyes is 0.25 seconds. The exposure calculated with this time cannot exceed the MPE value. Usually laser light below 1 milliwatt will cause dizziness, so you can't directly illuminate your eyes with this kind of laser, let alone observe this laser with telescopic equipment. If the beam of the third-level standard laser directly hits the eyes, it will cause damage to the eyes. Its output power is between 1 and 500 milliwatts. The four-level standard laser is a high-output continuous laser. Its output power is greater than 500 milliwatts, which may cause a fire hazard.