Laser pointers are compact instruments consisting of a low-power, visible light laser, used for pointing out features on a projected visual display. They are often used in training and other educational settings to highlight data on a large screen, as well as in industrial settings for checking machinery and parts for defects. Laser pointers are generally available with projected light in one of three colors, green, bright red (<650nm), or blue (650nm+).
Laser pointers are generally wand or pen-shaped and sized, and therefore easily portable. Most types function using batteries, although some AC plug-in types are available. The obvious difference between the two is that the battery-powered devices can be carried anywhere, while plug-in laser pointers are limited by access to a power source.
Laser pointers are compact instruments consisting of a low-power, visible light laser, used for pointing out features on a projected visual display. They are often used in training and other educational settings to highlight data on a large screen, as well as in industrial settings for checking machinery and parts for defects. Laser pointers are generally available with projected light in one of three colors, green, bright red (<650nm), or blue (650nm+).
Laser pointers are generally wand or pen-shaped and sized, and therefore easily portable. Most types function using batteries, although some AC plug-in types are available. The obvious difference between the two is that the battery-powered devices can be carried anywhere, while plug-in laser pointers are limited by access to a power source.
The output power of laser pointers is generally measured in watts, and indicates the "strength" of the laser beam. A watt is one joule of energy per second. This does not necessarily correspond to "brightness,” of the laser, which is wavelength dependent. A green laser pointer will be brighter than a red laser pointer of the same power because the human eye picks up green better.
Care must be taken when working with laser pointers. Some styles, especially more powerful types, which correspond to Class III and Class IV CDRH classification (Center for Devices and Radiological Health, part of the Food and Drug Administration, laser safety classification scheme), can cause ocular damage if used incorrectly. Laser pointers, even less powerful ones, should never be pointed directly at anyone’s eyes.