coversion crystals?

I saw a video on youtube about "laser conversion crystal" that turned a 808nm beam into 532nm.
Comments is disabled and not much info https://www.youtube.com/watch?v=JzWt22ugr7s

It just says it turns 808nm 500mW to 200mW 532nm.

What are these crystals?
How do they work? Like dichros?
What colors can you get with them? Just IR to green (532)?
Does their cost even make it worth using them instead of getting a beefier diode or beam combining?

They work by changing the wavelength whem the laser passes through it and eventually to 532nm. The laser that comes out would have not only 532nm but also 808nm. If I am correct, this is called diode pump solid state.
BTW, it will makes thing easier for everyone if you just google

Just like marcuspeh said, these crystals change the wavelength of the light passing through them. Most common are frequency doublers, which take 1064 down to 532. I'm pretty sure you can make some of the yellow wavelengths through solid state laser pumping if you have the right crystal. If you want to look into it, ebay has them from time to time, or you can go here https://www.mi-lasers.com/product-category/other-lasers/yag-solid-state-lasers/

marcuspeh said:

BTW, it will makes thing easier for everyone if you just google

Click to expand...

Thanks for the info.
Yes, I do google things before asking in an online message board, it's usually faster for getting info. But not always, especially when I don't know what to google.
In this case by searching "laser crystal" I mostly got results for these:


And just product pages listing several such crystals without explaining how they work.

So I couldn't find answers to my questions, which were (more detailed this time)
What are these crystals? The only infos I found say it's a gain media for lasers, but in the video you're loosing power in cost of switching the wavelength. What are you amplifying then?
How do they work? Like dichros? I mean does the laser beam just pass through it? Is there any requirement to be met, like distance and/or angle of the crystal from the diode? Some kind of insulation?
What colors can you get with them? Just IR to green (532 + ir)? I only found one video showing how 808nm is converted to 532nm with 60% power "loss"
Does their cost even make it worth using them instead of getting a beefier diode or beam combining? By this I mean cost wise is it even worth getting say a powerful 808nm c mount diode and trying to convert it to 532 nm, or is such crystal or anything else required for them not cheaper solution itself.

I apologize if I seem like someone whos too lazy to research himself, I honestly just can't find the info I want from what I search. Same was the case with knife edge combining. Google gave me nothing until the folks here shared their knowledge.
Thanks for all your responses.

These are the crystals used in DPSS (diode pumped solid state) lasers. All dpss based lasers use crystals to convert the output of an 808nm diode into a higher wavelength. 532, 589, 594, 607, 473nm are a few of the more commonly known wavelengths that use this process.

These have a 2 step conversion process using two crystals. The first crystal converts the 808nm light to 1064nm. ND:YAG and ND:YV04 are two of the most common for this. The 1064nm light exiting the YAG crystal is coverted to visible light by a KTP (potassium titanyl phosphate) crystal. There are other lines produced in the YAG that are weaker than 1064. These other wavelengths are used to get wavelengths other than 532nm.

That's the basic rundown. For more info, on all things laser, check this link.

Kevin520 said:

Just like marcuspeh said, these crystals change the wavelength of the light passing through them. Most common are frequency doublers, which take 1064 down to 532. I'm pretty sure you can make some of the yellow wavelengths through solid state laser pumping if you have the right crystal. If you want to look into it, ebay has them from time to time, or you can go here https://www.mi-lasers.com/product-category/other-lasers/yag-solid-state-lasers/

Click to expand...

Yellow, and some of the other more exotic wavelengths aren't as simple as having a laser pass through a couple crystals. Nd:YVO4 and Nd:YAG paired with a KTP is very forgiving, but for generating say, 589nm you would need to use sum frequency generation, rather than just second harmonic generation. With KTP you don't really have to phase match, as I said it's very forgiving, but when you get into the more complex stuff it becomes essential. You'd probably need a degree in photonics. Basically what happens with second harmonic generation is two same energy photons combine, halving the wavelength, to create one higher energy photon. In sum frequency generation, two different photons combine, which makes it that much more complex. Trust me, if it was as easy as passing a laser through a few crystals then everyone would have yellow lasers .