Recent content by louis54000

Thanks for the tip :)

Your PayPal address should be your billing address I think. That shouldn't be an issue! You can pay with a friend's PayPal account or with yours for a friend so I don't think you need to worry about it ;)

They are all tested with IR filter so you're good (it will be >300mW even with IR filter). And you'll see it's truly amazing. Got mine quite fast (ordered 4 lasers so I had to pay 25$ for customs). All 4 are great.

Well don't buy cheap glasses. I don't have a precise recommendation but I bought 10$ glasses for my laser (same as yours, I really awesome by the way!) but it melt the glasses... So don't go cheap. I usually don't use glasses because I use it outside. If you use it inside without glasses (not...

Thanks, I'll have a look. Well I need to explain for 10 minutes green DPSS lasers. Therefore I need an overview of how SHG works, I don't need to go in depth (it's not a 1hr lecture, I wouldn't have time). So I think with everything on this topic it should be ok. Now I should put some...

Alright, thanks for that. In this case, we just need to use this trigonometry identity : sin²(wt) = 1/2-cos(2wt)/2 and there we got it then. Thanks again for your input.

Yes! You're right! I think (hope!) I got it now. That's what I didnt fully get! So it's the frequency of the new electromagnetic field that "dictates" the wavelength of the photons right? And as energy is conserved and if a photon as twice the frequency it has twice the energy, then it needs two...

Okay, I know that. This is not the physical mechanism described here (other link you gave): The Physical Mechanism The physical mechanism behind frequency doubling can be understood as follows. Due to the χ(2) nonlinearity, the fundamental (pump) wave generates a nonlinear polarization wave...

well once again, I already know all these links... I already did a lot of research. All of this is not in my native language, and I only kindly asked for someone to explain me simply, so I have an overview of how it works. Sams Laser faq helped me a lot for the global understanding of dpss...

yes I read these pages several times already (Wikipedia has a lot of complicated math in it)... I wrote what I understood but I'm not sure it's correct. That's why I'm asking for help.

Hi guys! I need help to understand how SHG occurs in KTP crystals. So far this is what I got : In the crystal : the pump wave (light) creates a polarization wave twice it's frequency (due to non linearity). This wave then creates an electromagnetic field. Is this electromagnetic field...

Yeah I agree, it's kinda the same with PCs it's cool to say I built it ! I'll probably build my next laser, but as you said, we have a lot to learn first :)

Damn I wish could have been there :D that's just awesome! I show people this picture and they tend to understand better :

Yeah that's a good answer, I'll remember it next time ;)

YES! Exactly ! I live in Montmartre (highest point in Paris) and I just NEED to go up there and try to shine my laser all over Paris.. But there are always cops at night so I need to figure that out... Maybe ask nicely and tell the guy that I might let him try it if he lets me :D