Laser Diode Wavelengths and DPSS Systems

[ARG]

266 355 375 405
435 442 447 450
454 457 473 480
488 491 500 510
514 515 523 526
532 543 556 561
589 593 633
635

637 640 655 656
660 671 680 685
690 705 722 730
785 800 808 825
830 845 852 879
880 885 914 915
940 946 965 975
980 1030 1047 1053
1060 1064 1085 1112
1122 1310 1313 1319
1342 1444 1450 1470
1530 1550 1573 1700
1870 1900 1940 2200


Copy and pasted from CNI lasers

 

[ElektroFreak]

CNI used to have a better layout in which the various wavelengths were separated into their types, DPSS or diode. Now it's just a list of wavelengths, but no reference as to the type of laser.

 

[ARG]

CNI used to have a better layout in which the various wavelengths were separated into their types, DPSS or diode. Now it's just a list of wavelengths, but no reference as to the type of laser.

You can still click on the wavelength and it will tell you at the top of the page if it is diode or DPSS, but still not as useful as their previous page layout.

 

[rhd]

CNI used to have a better layout in which the various wavelengths were separated into their types, DPSS or diode. Now it's just a list of wavelengths, but no reference as to the type of laser.

EDIT: You basically have everything from 370 to 520 covered by InGaN diodes, and everything from 620 to 760+ covered by InGaAlP. Where in those ranges you actually want a diode to fall is just a matter of how much money you have to spend. The really bleeding-edge wavelengths (like the 520s or 620s) are quite expensive. For everything else, cost and availability is much more tied to whether that particular wavelength has been produced in mass for a commercial application, than it is tied to any sort of technical or intrinsic cost of manufacture. In theory, your list should probably have 370 to 520 blocked off, because everything in that range is diode-able. But in practice, we can only secure (affordably) diodes that are roughly meant to be 405/445/510. With moderate wealth, we can also secure 473/488/520, and with insane wealth, we can get anything anywhere in the range (as a custom wavelength). The same is somewhat true of the red range. Common wavelengths like 635/640/650/660 are cheap. As you deviate, it gets more expensive. 622nm for example, costs a fortune.

You can always just Google intelligently to get the categorized wavelength list like before:

FOR DIODES:
allintitle: "diode laser" UV OR violet OR blue OR cyan OR green OR yellow OR orange OR red site:cnilaser.com

FOR DPSS:
allintitle: "laser." UV OR violet OR blue OR cyan OR green OR yellow OR orange OR red -diode site:cnilaser.com

 

[Sigurthr]

Re: Laser Wavelengths? (laser diodes)

There's no way (that I've heard of) to hit 589 or 593 with a diode. Though I don't know why it wouldn't be possible in theory with InGaAlP. We use that for 589nm LEDs.

I was thinking about this to myself the other day. Unfortunately I don't know enough about laser diode construction, so I didn't post a "hey if we have 589nm LEDs why can't they just make one with a much smaller active region and form an optical cavity around it to make a 589nm laser diode?" thread. I searched and didn't see anything about it but didn't want to sound like a moron, haha. Would you happen to know any in depth details about why such a diode has not been made yet? I was under the impression that the only thing holding back new wavelength direct diodes was the lack of semiconductor that emits at the wavelength of interest.

Other than that, you probably need to add a few too:

- You're missing ~375nm from the NDU1113E / NDU7216E

I wonder what the price would be for one of these, haha. Would be great to see in a hobbyist's hands though.

 

[rhd]

Re: Laser Wavelengths? (laser diodes)

...why can't they just make one with a much smaller active region and form an optical cavity around it to make a 589nm laser diode?" thread. I searched and didn't see anything about it but didn't want to sound like a moron, haha. Would you happen to know any in depth details about why such a diode has not been made yet? I was under the impression that the only thing holding back new wavelength direct diodes was the lack of semiconductor that emits at the wavelength of interest.

There's virtually no demand. It's not really necessary for display technology, because red/green mix well to achieve yellow. I'm not real clear on what we even use small 589 DPSS systems for, outside of research. Larger 589s are used for astronomy, but there's just basically no demand for a yellow laser diode, so nobody is trying to make one.

I wonder what the price would be for one of these, haha. Would be great to see in a hobbyist's hands though.

Nichia's UV laser diodes are about $4k.

 

[sopark4000]

Re: Laser Wavelengths? (laser diodes)

I was thinking about this to myself the other day. Unfortunately I don't know enough about laser diode construction, so I didn't post a "hey if we have 589nm LEDs why can't they just make one with a much smaller active region and form an optical cavity around it to make a 589nm laser diode?" thread. I searched and didn't see anything about it but didn't want to sound like a moron, haha. Would you happen to know any in depth details about why such a diode has not been made yet? I was under the impression that the only thing holding back new wavelength direct diodes was the lack of semiconductor that emits at the wavelength of interest.



I wonder what the price would be for one of these, haha. Would be great to see in a hobbyist's hands though.

Really it comes down to demand. The reason that certain wavelength's are cheaply available while others are not is because of there use in widespread electronics. We NEED 405 for bluray, we NEED 445 for projection we need 650 for CDs. If some widely used electronic needed 589nm lasers than chances are we would have cheap access to 589 diodes already. A lot of the big developments in diode technology have been the result of research funded by the companies that are going to use the diodes in there products. Basically when it comes to diodes it seems people are only willing to fund research into wavelengths that are economically profitable. For example whoever owns the patents on the first economically viable green diode is going to be making a lot of money once the greens become widely used in projectors and other electronics. If I'm wrong about this someone please correct me but this seems to be the case for the most part.

 

[joeyss]

Re: Laser Wavelengths? (laser diodes)

There's virtually no demand. It's not really necessary for display technology, because red/green mix well to achieve yellow. I'm not real clear on what we even use small 589 DPSS systems for, outside of research. Larger 589s are used for astronomy, but there's just basically no demand for a yellow laser diode, so nobody is trying to make one.



Nichia's UV laser diodes are about $4k.

Could also be as you make the emitter size smaller you get to a point where the photons cause COD with the material and make it go LED.

http://www.ledmuseum.candlepower.us/ledamb.htmm

Looking at the spectra and the peak these guys are pretty damn close to high semi-coherence. If you were to make the emitters a bit smaller and focus it through a pinhole and use some optics....it might not be 100% a laser, but it could probably be done cheaper then buying a yellow...

 

[joeyss]

Just want to add something intresting I read in the Laser FAQ....

The keyword here is you have a CHEAP laser pointer. I'm going to presume the injection crystal lattice has contaminants in it, more likely if the manufacturer also builds LEDs in the same factory. What you are getting from your laser is a RED laser beam, and possibly green, orange, and yellow LED light (non-coherent) which is also coming from the same crystal. Fire it through a prism to see the various lines, I bet it's so polluted with foreign dopants, that it produces a bright red coherent line, and a few non-coherent red lines, an orange line, a yellow line, and a green line. That's all possible since the injection diode crystal is basically an LED crystal with perfectly cleaved ends, and a channeled electron injection pathway, axial to the beam.

You can typically see this effect if you test the cheapest LEDs you can find with a prism. I've found that dirt cheap green LEDs usually produce both a green and a yellow line. Dirt cheap reds produce several lines of red. You can get many wavelengths out of a gallium arsenide crystal.

Seems to me it might be dumb luck in order to make a yellow diode. I know their not easy ,but if it's another like red leds and red diodes it might just be a matter of remaking the crystal into a laser one and changing the dopant the hard part is figurering out the change...maybe?

 

[Hiemal]

If only we had access to a clean room and some Gallium arsenide...