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ArcticMyst Security by Avery
665nm?
- Thread starter erik
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Trevor
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You have oddly specific wavelength requirements. I would expect an overdriven DVD burner laser diode to come in at around that wavelength - but that might not be controlled enough for your application.
Why do you need precisely 665nm? What amount of error or linewidth is permissible?
-Trevor
Why do you need precisely 665nm? What amount of error or linewidth is permissible?
-Trevor
daguin
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Laser diodes are "rated" for wavelength with a "range" (e.g. +-7nm) Also, as Trevor has alluded to, the wavelength will vary with temperature and current.
Peace,
dave
Peace,
dave
Trevor;
Hm, “overdriven” ? How do you mean?
Line width as in the width of the light/spectrum produced?
I have been experimenting some time now with LED for growing plants, and lately been wondering about lasers and if that might be a even better way to go since from what I have seen they have a much more narrow spectra than what LEDs produce. 665 nm is this case is one of the main wavelengths needed for growing.
daguin;
Current I would have guessed, just like with LED but I had no idea that temperature affected the wavelength. Does wavelength vary all the time depending on temperature, or does it start going off at a certain point?
Hm, “overdriven” ? How do you mean?
Line width as in the width of the light/spectrum produced?
I have been experimenting some time now with LED for growing plants, and lately been wondering about lasers and if that might be a even better way to go since from what I have seen they have a much more narrow spectra than what LEDs produce. 665 nm is this case is one of the main wavelengths needed for growing.
daguin;
Current I would have guessed, just like with LED but I had no idea that temperature affected the wavelength. Does wavelength vary all the time depending on temperature, or does it start going off at a certain point?
Trevor
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Well, we run DVD burner diodes much harder than they are designed for - so, overdriven. 
If you want to ensure long life out of these diodes while running them continuously, you might not get them up to 665nm.
A lot of companies make red LED's - those will generally be easier to work with and less touchy than laser diodes. Have you had limited success finding LED's that emit the wavelength you're looking for?
-Trevor
If you want to ensure long life out of these diodes while running them continuously, you might not get them up to 665nm.
A lot of companies make red LED's - those will generally be easier to work with and less touchy than laser diodes. Have you had limited success finding LED's that emit the wavelength you're looking for?
-Trevor
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Ahh, okay, I see..
I will keep what you have said in mind for future experimenting, but it is probably as you say not controlled enough. Need to invest in a spectrometer first in that case, and they do not come to cheap
I have been in contact with many hundreds of companies that produce both diodes and lamps, extremely hard to find any that can do exactly 665. Of all the wavelengths I need this is probably the hardest one to find. My current manufacturer got it to peak at 667nm, and that is the closest I have ever found for any (high power) LED.
I will keep what you have said in mind for future experimenting, but it is probably as you say not controlled enough. Need to invest in a spectrometer first in that case, and they do not come to cheap
I have been in contact with many hundreds of companies that produce both diodes and lamps, extremely hard to find any that can do exactly 665. Of all the wavelengths I need this is probably the hardest one to find. My current manufacturer got it to peak at 667nm, and that is the closest I have ever found for any (high power) LED.
eexe
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Does it have to be EXACTLY 665 nm? What do you use for other wavelengths?
It would work if the wavelength were a bit higher or lower, but it would not be optimal. To use for example 660 nm instead there would be about 10-15% less energy uptake in a plant.
But I think I will have to settle for 660 for starters, and take it from there if I get any good results.
In this case when my main interest just is measuring growth only blue of 480 nm is needed. Had a look at Google before and saw that its pretty available so no problem there at least.
But I think I will have to settle for 660 for starters, and take it from there if I get any good results.
In this case when my main interest just is measuring growth only blue of 480 nm is needed. Had a look at Google before and saw that its pretty available so no problem there at least.
By the way...
Does anyone know where I can get appropriate lenses for splitting up light from a laser from a little dot to a rather big one? Kind of like the heads you get with some hand held laser pointers but instead of “i love you” or a star I need just a big blob of light
Does anyone know where I can get appropriate lenses for splitting up light from a laser from a little dot to a rather big one? Kind of like the heads you get with some hand held laser pointers but instead of “i love you” or a star I need just a big blob of light
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Well, if you want it to be *really* diverged, just take lens off of the laser!
Trevor
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You'd probably be looking at ~30 degree divergence, I think.
-Trevor
-Trevor
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^ He's got it.
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Good luck! Let us know the results!
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I'm certainly no plant expert, but why use red at all? Google tells me that blue has a better absorption.
