Laser Pointers  are pen like pointing  devices that are powered by batteries and work by emitting laser lights of different colors. Lasers pointers are useful in various applications and many professionals carry it with them  always. The laser pointer is available in different intensities and colors. Milli watts are  the unit to measure the power or intensity of a  Green Laser Pointer . Although, the safety  levels to avoid any hazards for laser pointer is defined within the range of 5 to 10 milli  watts, but due to the practicality laser pointers of high power within the range of 50 to  200 milli watts are used for professional purposes most countries have set regulations in  their use. Laser pointer could have four possible types, Red laser pointer, blue or violet  laser pointer, green laser pointer and yellow laser pointer. Red laser pointer is the most  conventional and simplest of the laser pointer variety available. The red laser pointer is  the first of its kind to hit the market in early 1980s. It was very expensive then but now  it is the cheapest one of the lot. Other type is yellow laser pointer; the yellow laser  pointer is inarguably the least commonly used laser pointer. Although, the level of light  emitted ranges between 1 to 10 milli watts, which is perfectly aligned with the standard  health guidelines. However, different results in different temparature are a major hindrance  in its popularity. Next in line is Green Laser pointer, which is quite common these days.
Green laser pointer can do what red laser point can do. Apart from that green laser pointer  is also considered suitable for underwater and scientific usages as well. Finally, Blue or   High Power Laser Pointer needs to be  mentioned. Blue or violet design and modus operandi is basically similar to the way green  laser pointer works. They can be used for conventional task of pointing to important stuff  in a presentation. However, their major usage lies in underwater, star gazing and other  scientific procedures.