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Success shifting wavelengths of single mode 660nm diode laser using diffraction grating method

liveforphysics

liveforphysics

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Jun 19, 2010
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A few folks here mentioned to me shifting a laser output wavelength with a diffraction grating. It seemed too amazing to be possible, but it works! The magic is getting a setup reflecting a portion of the gratings reflection right back down the laser diode. Able to shift this 660nm single mode red laser to 657nm, and at this point it seems the second order (or some other second mode generating effect?) shows up with this 1800lines/mm sinus etched diffraction grating.

Thank you to Single Mode here and Farbe2 for bring me awareness this was even possible. What an incredibly useful tool!

 

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Yeah, singlemode was doing this several years ago when I met him. I used to sell him diodes that I had binned by wavelength. He lived in Germany then, but is now in California. You won't find a nicer guy.
 
Our RnD facility is in El Segundo CA, and we live in Manhattan beach CA. It would be an honor to have Singlemode visit us anytime! I will give him a ride in a Tesla Plaid Model S that will blow his mind. I would love his help setting up an array of very narrow spectrum observing spectrometers for improving my DIY Raman rig.
 
3-5% feedback is all you need, so a carefully chosen beam splitter, Ar coated one side, 3-5% Fresnel Reflection other side with a grating works for large blues and greens, shifts of 7 nanometers have been observed. If you need stable frequencies for Raman, your looking at "Littman-Metcalf" setups at grazing incidence in a temperature stabilized housing.
 
Sorry Paul, I'm catching up. Last two years I have been devastated between the day job collapsing post Covid and being my late mother's legal guardian.

Steve
 
LSRFAQ said:
Sorry Paul, I'm catching up. Last two years I have been devastated between the day job collapsing post Covid and being my late mother's legal guardian.

Steve
Click to expand...

No problem Steve. Been there done that except the covid. Have gotten 6 vaccines since covid started. :)
 
I think you can shift via temp even more. Using temp is generally how 808nm diodes are tuned to match a lbo.
 
Not all semiconductors allow much thermal shifting. InGaN/GaN certainly doesn't. Red semiconductors are more responsive.
 
paul1598419 said:
Yeah, singlemode was doing this several years ago when I met him. I used to sell him diodes that I had binned by wavelength. He lived in Germany then, but is now in California. You won't find a nicer guy.
Click to expand...
Do you still happen to have few high binned red diodes?
 
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