Ooops, have i wasted my cash?

Infra-Red or IR is a byproduct of producing 532nm Green light...
The IR that comes out of a green laser is much more spread out
than the green beam... That is why it is dangerous if you are
near the aperture without IR Safety Goggles...
Remember the IR is invisible to the naked eye but it is still there..

Having a proper IR filter will not make the Green beam look dimmer
to the human eye...

The total power being read by any Laser Power Meter is all of the
wavelengths and combined beams hitting the LPM sensor at the
same time...

If your Green Laser has an IR Filter the extra power that may be
produced by the IR will not get to the LPM Sensor... hence a bit
lower power reading...

If your Laser does not have an IR Filter... and since the IR diverges
faster than the 532nm... you can get an almost only 532nm reading
on an LPM by placing the LPM Sensor as far as possible from the Laser's
aperture.

@wf.... if you wanted a 200mW Green laser that was guaranteed to
put out at least 200mW... then you would need to spend this kind
of $$$$$....

Green Laser Pointer from Wicked Lasers - Spyder I Pro


Jerry

lasersbee said:

Infra-Red or IR is a byproduct of producing 532nm Green light...
The IR that comes out of a green laser is much more spread out
than the green beam... That is why it is dangerous if you are
near the aperture without IR Safety Goggles...
Remember the IR is invisible to the naked eye but it is still there..

Having a proper IR filter will not make the Green beam look dimmer
to the human eye...

The total power being read by any Laser Power Meter is all of the
wavelengths and combined beams hitting the LPM sensor at the
same time...

If your Green Laser has an IR Filter the extra power that may be
produced by the IR will not get to the LPM Sensor... hence a bit
lower power reading...

If your Laser does not have an IR Filter... and since the IR diverges
faster than the 532nm... you can get an almost only 532nm reading
on an LPM by placing the LPM Sensor as far as possible from the Laser's
aperture.

@wf.... if you wanted a 200mW Green laser that was guaranteed to
put out at least 200mW... then you would need to spend this kind
of $$$$$....

Green Laser Pointer from Wicked Lasers - Spyder I Pro


Jerry

Click to expand...

Thanks for explaining that better than I did...

I didnt mean that an IR filter will make the beam look dimmer, what i meant was a 200mW non IR filtered beam would be slightly dimmer than a 200mW pure green (IR filtered) beam, as it would be a 200mW mix of green and IR, rather than 200mW of pure green...

Dusty said:

Thanks for explaining that better than I did...

I didnt mean that an IR filter will make the beam look dimmer, what i meant was a 200mW non IR filtered beam would be slightly dimmer than a 200mW pure green (IR filtered) beam, as it would be a 200mW mix of green and IR, rather than 200mW of pure green...

Click to expand...

You are correct.... since without an IR filter we can't see the extra IR
output power..

Jerry

Flaminpro, so even though when the laser is focused to a small dot the distance it will travel will be the same & the concentrated do will be able to burn where the dot hits or would that distance decrease!?, if so, why not have it permanently focused as i'm presuming thats what we all want isn't it?, a bright concentrated laser! if the laser is unfocused, we get a bigger dot & won't it be less bright or concentrated!, why would we want that??

Ok Dusty & laserbee, so whether the laser is with IR filter or not, its not gonna be visible to the naked eye, it just has extra energy (IR) near the aperture, its a bit like carbon monoxide, its there but you can't see it!!
A mixture of green light & IR minimally dims the laser, but i guess greens with no IR & no IR filter aren't possible are they?
A laser (like mine) without an IR filter at 200mW (near as), would be a bit less with a IR filter!

Jerry, spending nearly a $1000 i wouldn't have thought been worth the extra $850 for an extra 25mW would it? i mean they look good but, but not that much better! Susie said the O-like ones were guaranteed at least 175mW

I know the basics, this has made it clearer thanks!! Just why would we want an unfocused laser with less power & a bigger dot! Is it just more visible over distance or not! Would the laser be as powerful a beam & dot over 2000ft unfocused as focused!
& would my laser suffer from mode hopping everytime its not used for half an hour?

cheers

laser diodes are a point source, more or less. So, when you focus it, it will focus down to a point source. BUT only in one spot. Kind of like when you are looking through binoculars, you can see something very clearly, but stuff closer or farther is blurry. The beam coming from your laser is like a giant hourglass. The beam starts out as thick as the hole it is coming out of, or the lens it is going through. It then narrows as you go farther out, until it is as small as a point at a certain distance. further out than that it starts increasing in size again.

Do a google image search for beam waist and you'll get some good diagrams to help you visualize. When you change the focus, you are moving the waist (area of most concentrated power, highest lux, tightest brightest spot) closer and farther from you.

waterface said:

Jerry, spending nearly a $1000 i wouldn't have thought been worth the extra $850 for an extra 25mW would it? i mean they look good but, but not that much better! Susie said the O-like ones were guaranteed at least 175mW

cheers

Click to expand...

That's what I've been trying to get across... Here are 2 Reviews of
200mW Green Lasers with Graphs... One costs $1000.00 and the
other cost $150.00... For the Power and Price... which one do you
thing I would buy if I wanted a 2nd 200mW 532nm unit..

http://laserpointerforums.com/f52/200mw-wicked-lasers-spyder-i-pro-review-43206.html

http://laserpointerforums.com/f45/new-pocket-sized-200mw-532nm-laser-mni-review-43840.html


Jerry

Yeh i get that, so they both travel as far, but an unfocused laser over distance won't be as bright or powerful cos of the waste!! & when focused, there's less waste!
I guess if its unfocused, it could still burn if really close up as its the same coming out of the laser as it would be if focused. So i guess the beam unfocused gets weaker the more it travels because the divergence would be greater, it spreads out rather than is narrow!

A focused laser beam will almost always be smaller (and burn better) than
when it leaves the Laser's aperture....

Jerry

sorry Jerry i posted the other answer before i saw your 2 links! Its unbelivable they charge that much!!, but the higher average constant mW reading came from the WL at above the 200mW, but no excuse for price!

I noticed in the Dilda that the average was around the 200mW but more up & down & depending on batteries!
The ones that come with mine are Lithium batteries, but not sure what voltage, can i get higher voltage for more power, if so, whats the max?

I was thinking that if it arrives & batteries don't come for a week after, i may buy some disposables!!, in meantime!, i guess they would be significantly worse than the rechargeables i'm getting with the laser!

I don´t think that there is a better deal than the o-like, rayfoss 200mW grennies when you are looking for a high powered laser.
I don´t know what you expect about the laser, but when you´ve never held a laser with more than 5mW in your hands, I´m sure this one will blow your mind!!

:lasergun:

I'm not sure from reviews about the one i bought, but i shall have to wait & see!
I heard it has a 8ft wide dot at 3000ft which seems to mean it has lots of divergence, so how big will the focused do be?, 4ft!!

I hope it burns matches & has a good beam in the day as i've read on here that some 50mW lasers have day beam! I'm hoping i can light matches & zap street lights etc & amaze people with how it looks & really hope it has a descent beam & that the dot isn't too small!! It sounds like it may have the beam of a normal torch!!
Unless if the video on youtube has similar specs as my laser!!

Do all green lasers have mode hopping, even if cold for 30 mins they take ages to warm up & you can't leave it for half an hour & pic it up again expecting it to work the same!?

waterface said:

...but i shall have to wait & see!

Click to expand...

good point!

But 8ft dot?? My £9 1mW red pointer i bought in 1995 has a dot the same size however far away i am!! & i'm spending £100 on something i expect to be better!!

I just hope it looks & works like the rayfoss torch on the pics!

waterface said:

But 8ft dot?? My £9 1mW red pointer i bought in 1995 has a dot the same size however far away i am!! & i'm spending £100 on something i expect to be better!!

I just hope it looks & works like the rayfoss torch on the pics!

Click to expand...

That is not possible..... ALL laser beams have some divergence...

And if your (soon to arrive) Green Laser is focusable... then you
possibly have some control over the 8 foot beam diameter at
3000 feet... if that in fact is the case..
Not to mention... that at 3000 feet you could barely see the dot
with your bare eyes...

Jerry

Thanks for that, i was thinking it was strange, i mean 8ft!!

What is actually the point in having a laser that has a nice focused dot, only for it to be made huge by defocusing?? Maybe i'm missing something, but when you have a focused do that burns & looks great, why not just leave it at that!
I'm thinking the focusing is for items to be burned over different distances, similar to how you would focus binoculars for vision over distance?? Kinda like to 'home in' on the object! I'm kinda thinking that when its focused & all looks nice, why make it worse?


Is there any use for an unfocused laser?, maybe a nice fat beam in the sky looks nice?

I spoke to Susie & she says this laser is tested at 180mW+ & has a divergence of 2.0 mrad(please decipher if this a good number)!! & i have to rest it for 40 secs between 1 min usage time!

Will reply asap, internet down at home grr!

thanks

waterface said:

I spoke to Susie & she says this laser is tested at 180mW+ & has a divergence of 2.0 mrad(please decipher if this a good number)!! & i have to rest it for 40 secs between 1 min usage time!

Click to expand...

There is a lot of info on the Forum about calculating the divergence and
what it means...

Just do a little research finding it... That will keep you busy while
you impatiently wait for your Laser...

Remember... the [Search] button is your friend.. (I had to Rob)


Jerry