The laser in a laser pointer is the light emitted by the particles around the atom during the energy jump after being excited by a photon. It is characterized by high brightness, high directivity, high monochromaticity and high coherence. Its beam is able to focus precisely on the focal point and produce a high power density, causing high temperatures near the focal point, i.e., the thermal effect of the laser.
Early laser pointers used helium-neon (HeNe) gas lasers with a wavelength of 633 nanometers (nm), which were typically used to produce laser beams with energies of no more than 1 mW. The cheapest laser pointers use a deep red laser diode with a wavelength close to 670/650 nm. The slightly more expensive ones use a red-orange diode with a wavelength of 635nm, a wavelength that is more easily recognized by the human eye. Other colors of laser pointer are also available, the most common being green with a wavelength of 532nm.
Expanded Information
Besides safety, caution must be exercised when using a laser pointer. In art galleries, it is not appropriate to use a laser pointer because some paintings may be afraid of light. In zoos, laser pointers should also not be used to avoid scaring animals.
Astronomy enthusiasts should be careful not to use laser pointers too often or for too long, so as not to interfere with other people's stargazing and photography. In crowded public places, the use of laser pointers should be stopped to avoid accidentally injuring others. Some higher power laser pointers will have significant thermal effects and should not be used continuously for long periods of time, especially solid-state lasers that are more sensitive to temperature.
While the laser pointer is powerful and can do a lot of impossible work. In the market to obtain the majority of consumers praise. But you should also pay attention to safety when you use it.
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