What's the difference between a red laser pointer and a green laser pointer?

There are indeed blue and yellow laser pens. The differences between red laser pens and green laser pens are as follows:

1, different brightness

Because the spectrum of the human eye in the green area is the most sensitive reason, people will feel brighter when they look at the green light emitted by the green laser pen than the red light emitted by the red laser pen.

2. Different luminous principles

The red laser pointer is the simplest laser pointer in structure, because there is a laser diode to generate this wavelength, so only a battery-powered diode is needed. The green laser pen first generates nonlinear crystal with infrared laser with wavelength of 808nm, then generates infrared light of 1064nm, and then generates it by frequency doubling.

3, the scope of use is different

Although both red laser pens and green laser pens can be used for electronic teaching and demonstration, red laser pens are more common in this respect. In addition, the green laser pointer is often used to point out the stars and constellations, while the red laser pointer has no such use.

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