What are laser pointers?
Laser pointers are tools used for pointing out objects or locations, and are defined as “surveying, leveling, and alignment laser products” in an FDA regulation. They are commonly used during lectures and astronomy presentations, and laser pointers incorporated into spirit levels and hand tools are also very popular. In recent years laser pointers have become readily available, and are commonly sold in hardware, pet, hobby, and office supply stores.
The laser pointer was originally invented as a handy tool for lecturers or speakers to focus attention on particular part of a screen or chalkboard. But since the early 90s, these devices have become extremely cheap, and are now bought primarily for the sake of being a novelty electronics item. Most laser pointers use a 630 nm wavelength red laser diode, and are available very cheaply – usually between $1 and $10. Handheld lasers typically output about 5 mW (milliwatts) of power, making them Class IIIa laser devices which means that they are safe for consumer use. Green laser pointers have a 532 nm wavelength, and are about 50 times stronger than red laser pointers. These green lasers are viewable in mid-air (whereas red lasers generally are not), with a very long range of as far as 2.5km in heavy darkness. Green lasers are more expensive than red lasers, costing $50-$100. Even shorter-wavelength blue lasers are also in development. Laser pointers are typically about 1mm wide at their
by Administrator | post a comment The laser pointer was created for the use in speakers and lecturers to focus attention on a particular part of the chalkboard or screen. These devices have become very cheap in the early 90s, and are now purchased mainly for the sake of being an electronic item. Often, laser pointers use 630 nm wavelength of red laser diode, and are cheaply available. Handheld lasers usually output approximately five mw of power, which made them safe for safe for the use of consumer. Green laser pointers normally have 532 nm wavelength and 50 time powerful than the red ones. They are visible in mid-air, and ranges as far as two and a half kilometers. Some laser pointers generate light at a wavelength more than the viewable spectrum. Then, the spectrum is filtered two times is the frequency to generate a much more visible light. Cheap laser pointers along with other inexpensive devices, have been uses by hobbyist to create high-quality holograms. It can also be used in
