possibly the most perverse thing i have seen lately

[The_Doctor]

Brought in from alt.lasers because it will shock, astonish and amuse many, and I want to see what kind of response it gets.....




Subject: Re: Am I mad, or is this as insane as it looks?
From: Lostgallifreyan <no-one@nowhere.net>
Newsgroups: alt.lasers

Lasers In Mind <546@287.com> wrote in news:fhq275$8b2$1@aioe.org:

> Lostgallifreyan wrote:
>> http://rswww.com
>> Search: 442-3249
>>
>> Note the power. Note the COST!
>>
>> Note also that there are no special features like single longitudinal
>> mode, the thing is purely an alignment tool. Looks like the best scam
>> I've seen all year! Five years ago people could get away with it,
>> just. Not now, surely? What's going on?
>
> The '3 mW' on the tech' sheet is actually 2mW +-20&#37;!
>
>

Ok, this is now serious. This is a laser group with many professionals
visitng, even if they don't always post. This laser isn't even very stable.
Can anyone explain (I won't ask them to justify) this extreme excess?

WHY does some professional think they can ask &#163;602.74 plus VAT for what can
probably be exceeded by a casual buy on eBay, or even a local market stall
by now? This laser, if a US citizen is buying, will cost them ONE THOUSAND
FIVE HUNDRED DOLLARS ($1500) before shipping. It's a 3 mW green pointer
with no special abilities, and poor regulation. The markup on cocaine isn't
as extreme as this, as far as I know.

Why aren't alarm bells ringing? (Other than mine). Or is there actually a
racket going on, on a wider scale that no-one here wants to comment on?


Edit: Sorry Dave, but that title fitted entirely too well not to abuse creatively.

[allthatwhichis]

There must be a link on that page we don't see... Does it come with the chocolate cladded beer serving girls? All I can say is the it better have an IR filter.

[buffo]

Did you perhaps happen to miss the beam size specification?

50 microns. That's .05 mm folks. Damn small. Like, smaller than any laser I've ever encountered by a factor of 10 at least! And the quoted divergence is .1mRad, which is awesome by any measure, and absolutely incredible considering the tiny beam diameter.

Now, it could be that the above beam specs are pure fantasy and they really are ripping people off. *BUT*, if the specs above are accurate, then $1,500 sounds reasonable.

After all, name one laser you've ever worked with that has both .1 mRad divergence *AND* a .05 mm beam diameter...

Anyone? Anyone? Buehler?

Before I ripped them a new one, I think it would be worth it to call them and ask about the 50 micron beam diameter and the .1 mRad divergence claim. If those are accurate, then I'd say you owe them an apology.

If not, then flame on...

Adam

[The_Doctor]

No, it's not that thin. 50 microns is the focussed spot size. Look at the data sheet, the beam is 3 mm coming out of the laser. I'm not attacking them without looking, you're closer to attacking me without looking. Any cheap acrylic asphere is capable of a near-diffraction-limited spot from a DPSS or direct injection diode, so a claim of 50 microns is actually fairly loose, for a spec at closest focus from a TEM00 mode laser.

A guy posted in alt.lasers to say that is IS a racket, of sorts. What he says happens is some military or aerospace client might buy, and must have the specs absolutely confirmed. Obviously it's easier to qualify specs to exacting standards if the specs aren't that high to start with. And that guy said they might only sell one per year... Actually I bet RS sell a few more than that.

It just proves what I've always believed, he who has the mightiest meters (actually, calibration sources) wins. And it doesn't matter a damn if their product is actually better or not. If it really did, the market could not support such practises, yet it always has, and astonishingly even now it obviously still does.

That divergence is good, but even that's no great deal. First, a close lens with short focal length can easily get less than 0.5 mr. Their 3 mm beam width means they're probably using a longer focal length, between 7 to 10 mm instead of 3 to 5. That makes it easier to do. What they don't tell you is that it's not going to be always that good. How can it be? For a start, temperature will change it. It's user adjustable. If you are persistent enough, most cheap lasers with user adjustable focus can get to around 0.25 mr even with a short focal length and a single asphere. They won't be specified for it though because few people are ever going to achieve it for long.

[buffo]

Ok - you're right. The *spec sheet* lists the beam diameter as 3 mm at the aperture. However, the main page (which also lists the specs) doesn't mention anything about the quoted 50 micron beam diameter being the focused spot size. It just says "beam diameter". (That's misleading, and is a reason to complain.)

I still contend that .1 mRad is *very* good no matter what optics you're using. Not $1,500 good, mind you, but still good. (Let's call it $400 good) I've never seen a laser with .1 mRad divergence in my life. The best I've seen is around .5 mRad. (Exempting beams that have been up-collimated to a larger diameter, that is.)

Bottom line, they might sell a couple of them a year. I bet the more informed buyers go elsewhere. Futhermore, I'd bet that if they lowered their prices, they'd sell a lot more of them. But from the looks of their site, I don't think that laser modules are a very large portion of thier business, so there's no incentive for them to do so. They charge an arm and a leg, and for those people that are adamant about one-stop shopping, they can accomodate them while making a hansome profit. On the other hand, that profit pays for them to stock an item that they probably sell less than 10 a year of...

But a conspiracy? Hardly. Better calibration specs? Doubt it. It's just that they've built a name for themselves with high-end equipment (test gear, tools, and such) and so they decided that they can charge more. They're not the only company that does it, either.

Consider that your average 3-5 mw dpss green module sells for, what, around $50 or so on E-bay? (I'm referring to the self-contained ones that mount to a gunsight, which seem to be closest to what these folks are selling.) Now, ignorning the beam spec differences, that's roughly a 30-fold difference in price.

But what about this keychain red laser pointer from Edmund Optics? They want $50 for the thing, when you can buy them all day long on E-bay for 99 cents. That's a 50-fold difference in price. Equally outrageous? Nah, just business as usual for Edmunds...

Eh - that's capitalism for ya. Buyer beware. Or at least, buyer be informed. And for damn sure the buyer needs to shop around... (Unless the buyer is Bill Gates!)

Adam

[The_Doctor]

I still contend that .1 mRad is *very* good no matter what optics you're using. Not $1,500 good, mind you, but still good. (Let's call it $400 good) I've never seen a laser with .1 mRad divergence in my life. The best I've seen is around .5 mRad. (Exempting beams that have been up-collimated to a larger diameter, that is.)

I'm not sure of actual details, without taking one apart, and I guess you'll not hold me to that particular expense. I stated a 7 to 10 mm focal length, but it could easily be more. First, it's easy to verify that a 4.6 mm CAY046 Philips asphere can get 0.5 mr. Now consider that most modest powered green DPSS lasers can get within 1 mr with a beam width 0.8 mm or less wide at aperture. Given that the posh greenie is 3 mm at aperture, and has a fairly long barrel, the focal length could be as much as an inch. Given that focal length and beam width scaling, 0.1 mr doesn't look so tough.

[kaz]

the only thing i can think of is that some how they have got point stability mixed up with beam divergence, the best laser i have ever owned which i bought for having ago at holograms several years ago had a beam div of 0.6 full angle @ 20mw 532 which i payed &#163;600 to be honest i have never seen one with that good a specs anywhere on the divergence side of things but now i shall try and find one i like a challange if anyone finds one first please put the link up

[yaddatrance]

This thread got me thinking, if the largest clear aperture is 0.05mm, at 532nm, you're going
to have at least >13mrad divergence... If the aperture at the optic is 3mm as stated
elsewhere, then the divergence can be as low as 1/4 mrad (assuming we're throwing money
at it)... but the beam will be 3mm in size... if the optic focuses a 3mm beam to a 0.05mm
point, then the divergence would be off the charts.

I do not believe it is possible with any conventional means to get a 532nm laser w/ a 3mW,
0.05mm beam and a 0.1 mrad divergence. It should not even be possible to get 0.1mrad
divergence from a 3mm beam...

If you throw enough money at it and have engineers who are good at skirting the edge of
physics, you can have 7mm beam w/ 0.1 mrad divergence for practical terrestrial purposes.

So I vote, scam or "special" specs.

[kaz]

well it does have the "special" specs price

[Banthai]

Doc said ....

possibly the most perverse thing i have seen lately

so you have not seen the "2 girls 1 cup" video yet then !


just a word of warning for those that go and search for it

it is the most perverse thing i have ever seen ..... and i could only watch the first 40 seconds before i switched it off ..... and im a hardened pervy of the 1st degree

all the best ... Karl