Green Laser Infrared Emission
While it may not be too common to find an infrared laser, there is a relatively unknown source, green lasers.
The most common green lasers are actually infrared lasers, emitting natively 1064nm light. There is a second crystal used to double the frequency, and half the wavelength down to 532nm, providing green light. The infrared light should then be filtered out to get only green output. In cheaper green lasers, and most pointer style green lasers, this infrared filter is very weak or completely omitted, so the laser actually emits both green and infrared light at the same time.
You can see below, in visible light, the green emission of the laser is completely blocked by the infrared filter. When viewed in infrared, however, you can see that the infrared portion of the laser clearly goes through the infrared filter.
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WARNING! DO NOT point the laser into eyes, especially when filtered with an infrared pass filter. Your eyes will not be able to see any light or realize they are being damaged, but the very strong infrared light is still there and can damage your eye.
