Measureing IR on my laser

[neokeelo]

I put this in the Safety section since it related to that.

I made a post a few months ago when I first got my Optotronics 150mW pen style laser. Even while using some OD 2.0 ratted safety glasses, after testing my laser's burning capabilities at a distance of about 1 ft. Even after just a few mins of use, My eyes felt strained kind of. I know my glasses are stopping the green light correctly though since I only see a mildly bright orange dot if I shine it at the white paper surrounding my black target in the center of the paper.

Is there any way to measure the amount of IR coming out of the laser using a laserbee or another type of device. I am pretty sure the physics department at my local university would have something like that I could use if I asked. These pen style lasers are supposed to have an IR filter so could it just be my eyes are overly sensitive to green light at such a close distance even though I am wearing the safety glasses?

 

[Grix]

It might be that your eyes gets tired of seeing red all the time through the goggles.

You can try viewing the dot after the goggles through a camera. Cameras can capture IR, and if there is a significant IR leak from your laser, you should see a bright white dot on the camera.

To meter IR with a LPM, just point the laser to the LPM through the goggles and see whether you get a reading or not.

 

[neokeelo]

What wont damage the goggles?

 

[Kulhu]

What wont damage the goggles?

yes but its worth it

 

[StardustSprinkles]

Also, i read somewhere that shining it through a translucent packet of soy sauce and then looking at the other side with a camera works, the soy blocks visible light.

 

[HIMNL9]

Find a photo shop, and ask them for the "end queue" of a developed diapositive film (is the black part that you usually throw away, when receive your dia ..... here, at least, the labs always deliver it with the dias, for proof that they developed and framed all the film)

this type of film (dia only, NOT negative), when become developed without being exposed, blocks all the visible light, but left pass almost all the IR band, so you can place it in front of the laser, and measure the IR power with a LPM, or see it with a camera (and, being a thing that you can usually get for free, don't matter if become ruined from the laser )