Metacelsus
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Laser Safety for Raman Spectroscopy
I'm thinking about building a Raman spectroscope. What safety precautions are required for a 50 mW 532 nm laser?
What I'm planning so far:
-build an opaque, matte enclosure for the spectroscope
-test optics with a 5 mW laser, then install the 50 mW one
-wear laser absorbing goggles with optical density 5 or greater
Are these precautions adequate? Are the goggles overkill? How would the necessary precautions change if I used a higher (100 mW) or lower (25 mW)
power laser?
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Sulaiman
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I have had 5 mW, 50 mW and 500 mW green DPSS lasers,
I felt quite safe with the 5 mW as the blink reflex is probably sufficient protection due to the eyes sensitivity to green light.
The 50mW I think would have been able to burn my retina if it hadn't died so quickly.
The 500 mW was fun but terrifying, I got rid of it after a very short while.
Don't forget that with the cheap laser pen types there is often a massive output in the infra red.
Sam's Laser FAQ is my first reference for such things
http://www.repairfaq.org/sam/lasersam.htm
and remember;
DO NOT LOOK AT LASER WITH REMAINING EYE.....
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m1tanker78
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Quote: Originally posted by Cheddite Cheese  | I'm thinking about building a Raman spectroscope. What safety precautions are required for a 50 mW 532 nm laser?
What I'm planning so far:
-build an opaque, matte enclosure for the spectroscope
-test optics with a 5 mW laser, then install the 50 mW one
-wear laser absorbing goggles with optical density 5 or greater
Are these precautions adequate? Are the goggles overkill? How would the necessary precautions change if I used a higher (100 mW) or lower (25 mW)
power laser?
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Point #2 is a good start. You'd be surprised how a speck of dust can scatter a laser beam in unexpected ways. Treat the 5mW laser as if it were a 1/2W
to build good habits from the beginning. Always wear eye protection rated for the wavelength and highest intensity + ~10% margin you'll be dealing
with. If you're going to build a custom enclosure, include a safety switch at least for the sample compartment area. A computer/MCU/FPGA-controlled
laser is prone to glitches. Don't trust your eyes to glitches or bugs!
Sulaiman brought up a good point about the absence of IR filters in the cheap greenies.
Chemical CURIOSITY KILLED THE CATalyst.
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Marvin
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I have a squiggle on my left eye from a 5mw green through a pinhole. I figured 200uw would be eye safe. I checked the beam for 808nm and it was much
lower than the green. I wish I'd aligned those optics with a webcam.
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Texium
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Thread Moved
22-11-2023 at 19:16 |
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