the more Powerful Laser Pointer and the greater will
Have you ever looked at a handheld 300mw laser pointer red and wondered how dangerous they were if shined directly in the eye? These devices are widely available, commonly used in lecture halls and generally considered harmless and safe. Laser pointers available in retail stores in the USA generally have powers of 5 mW. This power is visible to the human eye, but generally considered harmless because the human blink reflex prevents prolonged contact.
High-powered laser pens can do a lot more harm than just distracting an opposing player, like cause permanent blindness, and the fear is that the trend that's taken hold amongst European soccer fans will make its way to the United States.
These classes give users an indication of the degree of laser hazard. The higher the class, the more Powerful Laser Pointer and the greater will be its potential to pose serious danger if used improperly. More powerful classes of laser pointers exist – these are the Class 3b and Class 4 laser pointers (see FAQ below for further information). The laser beams from these pointers may reach a few hundred milliwatts (mW), and they are extremely dangerous. Licences are required to import, to possess and to use such lasers and the licence fees can be many times of the cost of the laser pointers.
Growing up in the early 90s, laser pointers were a rare and expensive brand of cool. Before I knew about the cheap red lasers that would soon grace keychains and pockets everywhere, the industrial-strength Laser Pointer Green a family friend possessed would fill me with nerdy awe. She’d remove it from its hard plastic housing, where it rested on a throne of soft foam padding, and use it as a dog toy. Turns out, dogs go crazy for lasers
Don't allow the laser beam to enter the eye. The laser beam is harmful to eyes, any contact will cause permanent damage. Not the laser point to the crowd, especially in the face Don't look directly with your eyes or using binoculars and other equipment to observe the laser beam on the remote control.
Why can lasers be dangerous?
A laser beam travelling through the air has a very long range because it does not diverge like a regular beam of light. The danger of a laser beam is that it can concentrate a great amount of energy in one small area. When carrying out surgery or in industrial applications, for example, a powerful laser beam burns and vaporises tissue and other material. This is why a powerful laser beam hitting the eye or skin can cause permanent injury. In particular, lasers which work on the wavelengths of visible light and near-infrared radiation are able to cause permanent damage to the retina of the eye.
A laser is a light source that can be dangerous to people exposed to it. Even low power lasers can be hazardous to a person's eyesight. The coherence and low divergence of laser light means that it can be focused by the eye into an extremely small spot on the retina, resulting in localised burning and permanent damage in seconds. Certain wavelengths of laser light can cause cataracts or even boiling of the vitreous humor, the fluid in the eyeball. Infrared and ultraviolet Green Laser 10mW are particularly dangerous, since the body's "blink reflex", which can protect an eye from excessively bright light, works only if the light is visible
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