Optical Wattage of LASER needed for Raman spectroscopy

  • Thread starter Thread starter sbrothy
  • Start date Start date
Click For Summary
The wattage of the laser used in Raman spectroscopy may not significantly impact the effectiveness of the setup, as the intensity of Raman scattered photons is much lower than that of the exciting photons. A stronger light source is generally preferred to enhance detection capabilities and minimize noise interference. The heat generated by higher wattage lasers is a consideration, but the choice of laser type may be less critical according to the referenced document. The discussion suggests that existing 650nm lasers could be tested for their effectiveness in the application. Overall, the focus remains on optimizing detection while managing noise filtering.
sbrothy
Gold Member
Messages
1,267
Reaction score
1,140
I'm currently using this document to purchase the parts I need. Being no expert, and looking on the table of the 532nm laser diodes used, it doesn't seem to matter much what wattage the laser should be. Is there any advantages to using either a low wattage or high wattage laser, apart from the heat deposited in the appliance?
 
  • Like
Likes Greg Bernhardt
Physics news on Phys.org
Intensity of Raman scattered photons is several orders of magnitude (wikipedia article suggests 10-6 range) lower than the intensity of the exciting photons, which makes detecting them difficult. My bet is you want as strong light source as possible (or, at least, you need to estimate whether your setup will be capable of detecting anything and filtering the noise from the original source away).
 
A procedure for filtering the noise is included in the paper. OTOH, from the paper, it doesn't seem to matter much which laser is actually used. I already have a couple of 650nm lasers. I could try with those....
 
Borek said:
Intensity of Raman scattered photons is several orders of magnitude (wikipedia article suggests 10-6 range) lower than the intensity of the exciting photons, which makes detecting them difficult. My bet is you want as strong light source as possible (or, at least, you need to estimate whether your setup will be capable of detecting anything and filtering the noise from the original source away).

So if I understand correctly 100mW is better than 5mW, right?

EDIT: And yes I realize how basic this question is. I just want to be sure it's worth the trouble, because a private person isn't allowed to buy a 100mW laser here. I have a registered company though....

EDIT2: And these 2 threads of mine should be merged really...
 
Last edited: