Wattage of LASER needed for Raman spectroscopy

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SUMMARY

The wattage of the laser used in Raman spectroscopy significantly impacts the detection of Raman scattered photons. A higher wattage, such as 100mW, is preferable over lower wattages like 5mW due to the increased intensity of the exciting photons, which enhances the likelihood of detecting the weak Raman signals. The discussion emphasizes the importance of a strong light source for effective detection and noise filtering, as outlined in the referenced paper. Additionally, the user notes the legal restrictions on purchasing high-wattage lasers as a private individual.

PREREQUISITES
  • Understanding of Raman spectroscopy principles
  • Familiarity with laser diode specifications, particularly 532nm and 650nm wavelengths
  • Knowledge of photon intensity and detection challenges in spectroscopy
  • Basic understanding of noise filtering techniques in optical measurements
NEXT STEPS
  • Research the specifications and applications of 532nm laser diodes
  • Explore the effects of laser wattage on Raman signal intensity
  • Learn about noise filtering methods in Raman spectroscopy
  • Investigate legal regulations regarding the purchase of high-wattage lasers for research purposes
USEFUL FOR

Researchers, optical engineers, and laboratory technicians involved in Raman spectroscopy, as well as anyone interested in optimizing laser usage for enhanced detection of Raman signals.

sbrothy
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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?
 
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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).
 
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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...
 
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