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The red laser penetrates through nuclear sclerotic cataracts and moderate vitreous hemorrhages better than lasers( http://www.htpow.com/300mw-green-high-power-laser-pointer-waterproof-adjustable-holster-p-1038.html ).This wavelength is also very popular because superpulsing the laser eliminate the risk of eye damage.There are no wavelength filters hidden in the head to separate the laser wavelengths.
The following summary table compares the wavelengths of various cold lasers.In addition to the gas-cell stabilised lasers( http://www.htpow.com/1000mw-laser-pointer-green-532nm-powerful-enough-p-1031.html ) already discussed.A single transit through a collection of excited atoms or molecules is sufficient to initiate laser action in some high-gain devices such as excimer lasers.
The surface of precision lenses and mirrors is measured using laser( http://www.htpow.com/highquality-500mw-burning-waterproof-red-laser-pointer-p-1067.html ) interferometers.Potential hazards to the eye depend on laser light wavelength, beam intensity, distance from the laser.It is possible to restrict the linewidth of a laser to less than 1 kHz, useful for scientific interferometric applications.
If you check the specs on a 660 nm laser( http://www.htpow.com/200mw-green-laser-pointer-pen-532nm-belong-to-cass-llla-p-1003.html ) diodes like the ones used in medical lasers.HeNe lasers are used in many national standards laboratories.Multi frequency laser systems emitting three or more wavelengths include multicolour RGB lasers that emit red, green and blue laser light simultaneously.What if my laser isn't exactly one of the predetermined wavelengths?
