Laser marker transmissivity in polycarbonate sheet

[tygerdawg]

I'm involved with setting up a laser marker station that will mark 6mm thick polycarbonate sheet. The laser is 1064nm wavelength, 10W power. Axis of laser is perpendicular to broad surface of the sheet. The laser focus point is inside the 6mm sheet thickness dimension, not on either upper or lower surface.

Area around the focal point will be shrouded for safety. The management is concerned that the PC sheet material will act as a lightpipe and transmit laser radiation out of the edges. I say, at 10W, not enough to worry about due to attenuation and dissipation. And if it does, then we can put simple blocking barriers around the periphery of the sheet to limit any exiting radiation.

The marker vendor has no idea.

Any thoughts?

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[IRstuff]

Au contraire, a 10W CW YAG is CLASS4!!!!. The AEL for CW YAG is 1.92 mW, which is only 0.02% of the beam power. Any little reflection or glint would instantly blind you.

Your ENTIRE setup should have been enclosed and interlocked. This is not a trivial matter.

I'm terrified that your company is willy-nilly using these lasers without a qualified laser safety officer (LSO). Get one, and get one NOW!!

Your company has opened itself to serious liability issues, and you should not be counting on the beneficence of internet strangers to answer laser safety questions.

TTFN

FAQ731-376

 

[BrianPetersen]

I second the above; YAG laser light is REALLY bad news. The whole operation needs to happen inside a laser enclosure with NO possibility of light escape. Not reflected, not transmitted. And you had better interlock it so that if someone has the laser enclosure open, the laser can't go.

 

[hacksaw]

even a reflected 5 mw beam will just about drop you to your knees and cause near permanent damage, 10 w will do more than harm your eyes,

it is nothing to play with

 

[tygerdawg]

Thanks for the comments and concerns. I guess I wasn't clear in my question. In a previous life I was an LSO so I'm aware of the dangers of 1064nm radiation. All reflection paths are to be properly shielded and proper safety precautions are to be implemented.

My question is whether or not anyone has any insight into the suspected lightpiping phenomenon of PC sheet.

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[IRstuff]

A light pipe is simply something that is operating under total internal reflection (TIR). Given the nature of the operation you describe, the beam is coming in at a very wide angle, to be focused into a small, and short, region. The high cone angle of the beam can result in some amount of TIR. Note that PC is used for fiber optics, so it does do TIR.

TTFN

FAQ731-376