For the ideal of laser pointers, in an ideal medium (such as vacuum) in communication is clearly not to see, the laser energy was concentrated in the beam, you will see the target there is no sign of the flash and corrosion wear, we do laser spot welding is the case. Of course, laser spot welding and laser beam energy is very low. Laser weapon is not a level.
If the increase of energy, we can see a line of laser pointers formed the roof of the building, such as many high power laser. This is the Tyndall phenomenon, light through the colloidal particles in the atmosphere, a part of the energy to the surrounding formation of blinding light scattering effect.
But note that different material laser pointers excitation frequency generation are not the same, if not necessary, not necessarily just fall in the range of visible light, laser spot welding applications are not visible at this point even if the laser scattering cannot see.
If the laser pointers energy to continue to increase the laser level, laser energy can ionize the air in the atmosphere, at this time you can see the white light, red or blue purple (according to different laser wavelength and power, can refer to the color of lightning).