3D Laser Scanning

[NNC]

I am building a 3D laser scanner for scanning faces.
I am looking for a line laser and eye safety.

Laser:
What sort of line laser would be optimal?


Eye safety:
The eye safety needs to only cover the eyes. Something like tanning goggles.

Reflective material will cause issues with the scan.
However, the eye safety doesn't even have to be transparent.
So I need to prevent the laser from passing through to the eye with no reflection.

 

[benmwv]

5mw line laser.

"Please close your eyes."

 

[pschlosser]

a 1mW line laser, in a darkened room, may not require eye protection at all. Although, the subject may need to keep their eyes closed during the scan.

 

[NNC]

I was hoping for some sort of physical barrier for the eyes. One of my college's has had laser eye damage in the past. He doesn't not care to repeat that.

 

[DrSid]

Sure .. safety first .. but with 5mW even direct beam hit should be safe. When the power is spread to line, it would be 100 times safer.
Green might be more visible. It is more visible to human eye. But you are going to use CCD camera right ? Then it depends on color filters on the camera, and red might be good as well.
As for generating line, there are two options .. rotating mirror, or line generating lens. The first produces line with very even brightness, but is noisy, mechanically complicated, it actually generates moving point, which can be problem when you are capturing it on video, and it also may stuck, which could be safety risk with higher laser power. Line generating lens are cheap, fail-proof, simple, but the line brightness varies a bit along it's length.

 

[robmobz]

Perhaps swimming goggles with matte black paint over the lenses.
Only costs around £3 to make a test set and would, at least as far as I can tell, do the job well enough.

 

[NNC]

Perhaps swimming goggles with matte black paint over the lenses.
Only costs around £3 to make a test set and would, at least as far as I can tell, do the job well enough.

Is there a cheap method of testing safety?

 

[Spectre Gadget]

If you're looking for absolute blockage of light, then yes, use the shadow method.

Attenuation must be calculated by a power meter, which is relatively expensive (for the average college kid). Not so much for some evil geniuses that frequent here.

Honestly, if you're trying to measure the attenuation a 1-5mW line generator produces with a particular piece of eye protection, you'll have problems anyway. The line will probably be too wide for the meter head, and too small to get accurate measurement.

 

[NNC]

Thank you everyone for your help.

I ended up finding what I was looking for by googling: "laser patient eyeshields"

Seems that these are used primarily in laser surgery.