The transmission distance of light is infinite, and the long wavelength light has a low refractive index and is difficult to be diverged. Green light is the most sensitive to human eyes, the same power lamp green light is several times the red light. In the case of a laser pointer, red light and blue light are typically emitted directly by a laser pointer diode and then focused by a lens. And green laser pointer light generally by infrared laser diode crystal frequency doubling for green light (also have direct generation of green light). Green light has a smaller divergence Angle and shoots farther than other laser Pointers. The general price is cheap, dozens of yuan, power false majority. General page night view range of 500-1000 meters is available. Businesses often describe thousands of meters or tens of thousands of meters.
However, this type of green laser pointer, generally marked tens of thousands of power, the actual power between 50-80MW, if can not focus the match, the power between 10-40MW. Using this power, the visual range is conservative at about 500 meters. Of course, the Internet will brag about thousands of meters, even tens of thousands of meters. You don't worry, buy back their own irradiation of the local target buildings, measure the distance to know the actual range. Generally speaking, the actual range of this model is 500-1000 meters, which is quite objective.
A Laser pen is a Laser diode. It has red light, blue light, green light, violet light and other types of rays, suitable for reporting, teaching, guiding, astronomy and other fields. The apparent brightness of the light spot not only depends on the power and surface reflectivity of the laser pointer, but also depends on the color vision of the human eye. Improper use may cause harm, such as retinal damage, skin injury, damage to precious goods, etc., which should be prevented from children. In theory, with a laser, you can shoot up to 10 kilometers. It depends on what the laser is used for and how much power it needs at the receiving point. The particle in the atom of some material is stimulated by light or electricity, so that the atom of low energy level becomes the atom of high energy level, and the radiation gives the light of phase, frequency, direction and so on exactly the same, this kind of light is called laser pointer, also called "laser pointer".
