Power Meter, Bragg Mount and Oudin coil (aka-argon laser toys)

[robotarmy]

Hey all!

I'm in the market for some or all of the following:

A power meter (5 Watts, hopefully I can push my ALC68 over 2W...) - Budget: £100? More if that's unreasonable?
A bragg mount for an AA AOM (can't remember the model number... will grab it when i'm near my laser next) - Budget: £50? not much, don't need it TOO classy...
An Oudin/Tesla coil to try and start an ALC60 i just picked up. - Budget: £30?

I don't REALLY know how much this stuff should cost, but I'm broke as hell from the last LEM so go easy on me!

Thanks!

[Jem]

... I'm broke as hell from the last LEM so go easy on me!

Haha... But it was money sooooooo well spent

[White-Light]

Hey all!

I'm in the market for some or all of the following:

A power meter (5 Watts, hopefully I can push my ALC68 over 2W...) - Budget: £100? More if that's unreasonable?

That's a bit optimistic.

I think the cheapest 5W I've heard of is Laserbee's 5W limited version and that's around £400 + shipping.

http://www.ebay.co.uk/itm/LaserBee-5...item23148d0ed1

Get onto most big brands such as Coherent and you're looking at least double that.

Cheapest you can self build for is around £200 for a device that uses a multimeter rather than being an integrated power meter (I know this for a fact as I've just done it!)

[robotarmy]

That's a bit optimistic.
I think the cheapest 5W I've heard of is Laserbee's 5W limited version and that's around £400 + shipping.
http://www.ebay.co.uk/itm/LaserBee-5...item23148d0ed1
Get onto most big brands such as Coherent and you're looking at least double that.
Cheapest you can self build for is around £200 for a device that uses a multimeter rather than being an integrated power meter (I know this for a fact as I've just done it!)

Ahh yeah, i thought it might have been... Don't need the meter so much as i have an analog multimeter that should hopefully work. I was looking at this ... http://www.ebay.co.uk/itm/Ophir-OEM-...item19c3d98f8c ... but I'd rather give my money to someone on PL than some random on EBay, not sure why.

Maybe 2.5 ish watts is more realistic? If i ever buy a laserscope or some CuBr thing i just might have to fork out, but i'm sure at that point the power meter will be a piss in the ocean of my problems

[White-Light]

That's exactly what I bought and it cost me around a further £60 to wire it up and case it.

I haven't tested it yet as I don't yet have a laser, but these are well established as power meter heads from what I can gather and quite accurate despite being tuned for 1064nm not visible light.

The seller is also very nice and helpful. He's awaiting my feedback only because I haven't been able to test. So far though 10 out of 10.

I'm afraid I can't disclose the wiring details because someone professional helped me out and didn't want me to reproduce them.

Ophir sensors are good but if your aim is audience scanning then be aware they are 113mm squared not 100 mm squared so you either need to do the extra maths as the area is 13% larger than it should be for taking MPE measurements (I'm not sure how it affects the final reading) or you need to get a new plate engineered for the front. I've already contacted Ophir and they don't make them for these heads. ATM I've asked my local university engineering dept if they'd help but haven't got a reply yet. Luckily there are 2 universities near me so I have 2 chances before having to engineer something myself. Tolerances are tight though for self manufacture,

[White-Light]

This is the inside of mine (i've blacked a little bit of wiring out just to make sure I keep my promise - not being unfriendly but a promise is a promise):



In addition I bought some multimeter lead extensions and re-terminated them with right angled plugs to create a dedicated set of meter leads:



This is the head piece that needs to be re-manufactured if you want 100mm squared (ie 1cm square):




It's also surprising though how costs mount up with just small items. It doesn't look like £60 worth of extras but even things such as drill bits add up!

If you want something off the shelf for ease, the Laserbee should be a good buy as it uses the same head but the note about 100mm squared also applies though if audience scanning.

[robotarmy]

What's the story with the 100mm^2 thing? I thought a dark-adapted pupil was 9mm diameter ish, so 64mm^2 (and if you want, i could probably make something that would fit that meter really, really easily. All you need is a drill press and some hammerite, or you could get it anodized)

[robotarmy]

(ps. please forgive me if i'm misinformed, I'm definitely open to more information about the safety side of lasershows, I've got a kind of "screw it, i'll keep it 3/2.5m away from an audience" kind of attitude for now considering i have no DAC, no software, and until the final hour of the last UKLEM i had no scanning or blanking)

[danielbriggs]

That's a bit optimistic.

Get onto most big brands such as Coherent and you're looking at least double that.

Cheapest you can self build for is around £200.

Al... this is simply not true.

I haven't tested it yet as I don't yet have a laser, but these are well established as power meter heads from what I can gather and quite accurate despite being tuned for 1064nm not visible light.

The seller is also very nice and helpful. He's awaiting my feedback only because I haven't been able to test. So far though 10 out of 10.

I'm afraid I can't disclose the wiring details because someone professional helped me out and didn't want me to reproduce them.

Ophir sensors are good but if your aim is audience scanning then be aware they are 113mm squared not 100 mm squared so you either need to do the extra maths as the area is 13% larger than it should be for taking MPE measurements (I'm not sure how it affects the final reading) or you need to get a new plate engineered for the front. I've already contacted Ophir and they don't make them for these heads. ATM I've asked my local university engineering dept if they'd help but haven't got a reply yet. Luckily there are 2 universities near me so I have 2 chances before having to engineer something myself. Tolerances are tight though for self manufacture,

^ Lots of clat.

WTF as per audience scanning...??? just read what Ryan posted.
He needs to meter his argon(s!)

Al, you win Tangent of the Year Award for the "university epilogue"!




Now back in the real world...
Ryan... you're after a cheap power meter right?
I might be able to rustle up a nice 10W Coherent head; maybe also dig out an old Coherent 201 meter to go with it...

The thing would need a metric fcuk tonne of calibration :-) but if you like a tinker, wouldn't be plug and play, but I could let it go for a price that might make this ok.

Lemme know if ya interested

[robotarmy]

Hah, yeah, that really was the tangent of the year! (I can still make a thingie if you want White-light, i'll sell it to you for something you think is reasonable... if you send me the plate you need to copy I'll knock it up at work, and if you need it anodized i can get you a quote)

Dan, if it's a go-er i'll take it... relative indication is pretty much what i'm after, for walking in mirrors and lining up optics like AOM's that's all i'll need (and i might just be able to calibrate it at the next mini-lem? maybe?) how low can it go usefully?