Humans can incur significant eye damage by exposure to invisible light before they become aware of it.
Green laser pointer with ir filter.
This is just one of the reasons that our green laser pointers are considered to be the best choice for quality reliability and safety.
Daniel rivera 2 337 views.
I use a cheap allegedly less than 5mw green laser pointer to point things out in the night sky at public astronomy events.
Today you can buy a green laser pointer the size of a ball point pen for 15.
Click on the image for a larger view.
Coatings and a filter allow only the green light to exit the device.
When opening the laser i found that there is no ir filter installed.
Cross section of a typical green light laser pointer.
This ir light can be eliminated with the addition of an ir filter.
Importance of an infrared filter in a green laser pointer.
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.
The infrared one can do something about.
Using camera in night mode i noticed that its shining a lot of ir which is invisible to eye.
Because of the narrow bandpass they do not adversely degrade color recognition.
The absence of an ir filter is usually to save cost at the expense of operator safety.
It has a very narrow band filter 25 nanometers that is claimed to eliminate 99 of 532 nanometer laser light.
Some cheap green lasers can emit up to 10 times the green light in invisible ir infrared.
Twenty years ago a green laser would set you back 100 000 and occupy a good sized dining room table.
You can see below in visible light the green emission of the laser is completely blocked by the infrared filter.
Unfortunately recent nist tests show that a lot of green laser pointers generate a lot of extra visible and infrared light.
All green laser pointers sold by laserglow have a quality ir filter installed and as a result there is no ir leakage from the laser diode.
300mw red laser pointer pop balloon duration.
The sperian laser gard model we examined is for nighttime protection against the most common green laser pointers.