Post your interesting eBay finds...

[SoulFeast]

Standard in relation to 594, meaning it's not some "new" 594. Frequency summation doesn't make it special. Technically, 532 is summation of 1064 + 1064. It's the different coatings that allow for two separate outputs of the Nd to resonate/gain, that makes it unique.

Also, I've stuck a 589 in the freezer to prolong the warm-up effects it has. Even when not frozen, it has an output of 3 or more lines, freezing prolongs this.

Those other lines are likely 671, and 532.

594 and 589 are very unique in design...

[mixedgas]

One thing to remember when calculating that is that it is the sum or Difference of the squares, not a direct sum so Fout is the square root of the quantity (F1^2 + F2^2)
It doesn't matter for doubling, but when you calculate difference generation you need the sum or difference of squares or the numbers are a bit off.
Just a FYI.

Steve

[buffo]

Technically, 532 is summation of 1064 + 1064.

Frequency doubling is not the same as frequency summation. See Steve's post above.

594 and 589 are very unique in design...

"Unique" is a synonym for special.

Adam

[The_Doctor]

That bit with the squares is nice, but my maths is lacking on this one, maybe. I tried using 300,000,000/wavelength in metres) as basis for frequency in Hz, then trying to get a result that looked like doubling or halving. I couldn't get one. I'm not above asking for a working example here, because this is something I want to be sure to remember right.

[andythemechanic]

Actually the square thing is not right, it is f_sum=f1+f2 for a simple reason: photon energy is proportional to frequency and sum frequency generation, or any other second order nonlinear effect is energy conserving so h*f_sum must be h*f1+h*f2, where h is Planck's constant.

Andreas

[mixedgas]

Actually I screwed up

Doubling is a special case of Sum Frequency Mixing. ie Omega/2

For any other case, for SFM in terms of wavelength, its 1/Final = (1/W1) + (1/W2)

Example for red, ND:YAG + a Picosecond fiber system, would give you:

(1553 SFM 1064), 1/1064 + 1/1553 = 6.43915003219575e-4 + 9.398496240601504e-4 = 0.0015837646272797, and if you take the reciprocal, its 631.4 nm.

If you want to get precise, its usually 1064.1 nm, but the bandwidth is typically .2 to .6 nm wide depending on the host crystal and the cavity its in.

Example for UV from a YAG system, for SFM 1064 + 532 (1/1064) + (1/532) = 0.00281954887, (1/0.002819) = 354.6 nm

For two line ND:YAG orange:

SFM 1064 + SFM 1319 (9.398496240601504e-4 + 7.581501137225171e-4) = 0.0016979997377827 so 1/0.0016979997377827 = 588.92 nm

Sorry for the confusion, but is the reciprocal of wavelength, not the square.

Steve

[The_Doctor]

Actually I screwed up

Doubling is a special case of Sum Frequency Mixing. ie Omega/2

For any other case, for SFM in terms of wavelength, its 1/Final = (1/W1) + (1/W2)

Example for red, ND:YAG + a Picosecond fiber system, would give you:

(1553 SFM 1064), 1/1064 + 1/1553 = 6.43915003219575e-4 + 9.398496240601504e-4 = 0.0015837646272797, and if you take the reciprocal, its 631.4 nm.

If you want to get precise, its usually 1064.1 nm, but the bandwidth is typically .2 to .6 nm wide depending on the host crystal and the cavity its in.

Example for UV from a YAG system, for SFM 1064 + 532 (1/1064) + (1/532) = 0.00281954887, (1/0.002819) = 354.6 nm

For two line ND:YAG orange:

SFM 1064 + SFM 1319 (9.398496240601504e-4 + 7.581501137225171e-4) = 0.0016979997377827 so 1/0.0016979997377827 = 588.92 nm

Sorry for the confusion, but is the reciprocal of wavelength, not the square.

Steve

Thanks. That makes sense. I actually tried reciprocals last night, realising that the 300,000,000's would all cancel so I might as well use 1/.... The reason it didn't work for me is I'd ended up doing it on the frequencies by mistake, I think, after getting derailed by the squares bit. As it is now it's really easy, exactly like calculating resistors in parallel or capacitors in series.

It also appears that Andy's summation of frequencies is correct too, as they're proportional to reciprocal of wavelength.

Btw, Andy, why is your avatar like a demon baby? I like to get these intractable technical details out of the way...

[andythemechanic]

Btw, Andy, why is your avatar like a demon baby? I like to get these intractable technical details out of the way...

Hehe no special reason. There was a Photoshop demonstration once, where the image of a baby was changed to many weird or funny baby-images. I liked that one, so it became my avatar. You can see the series e.g. here: http://forum.xcitefun.net/amazing-ba...gs-t30658.html

Andreas

[The_Doctor]

Nice. Shrekbaby, Batbaby. Good company. Fish-head eating martial arts master with whispy beard and weird gestures baby. He'd get my vote but he's too obvious. On the other hand, that expression totally fits.

[laserlackey]

Post interesting eBay finds, eh?

How's THIS? *drool*