which 637nm

[csg]

Hello there,

im fairly new around here, however have greatly enjoyed reading up on a lot of the threads.

to cut to the chase so to speak, im fairly new to the laser side of things, but have 20 odd years experience in the lighting industry. Last summer, i purchased a pair of RGB projectors with pangolin quickshow running things, with the purpose of providing some beam shows along with some of the lighting rigs i put in for dance events

the projectors are matched pair, outputting roughly 3.8w total, with a combination of 445, 532 and 650nm.

Whilst fairly well balanced in terms of white, i don't like the beam characteristics of the 650nm diodes, and my reading suggests that smaller 637nm modules would make a better bet. I am also intending on re-boxing the lasers as the current cases are small and dont allow a good layout, and i would also separate driving electronics and optics to minimise dirt build up etc.

So, goldenstar laser seems to be a good resource for parts, and they seem to have 2 options on the 637nm module. I am looking at 600mw, hoping that it will give same apparent brightness as the 1.5 - 2W 650nm modules currently in place.

so, am i better off with a laserwave module giving a 3.5mm near round beam with a 2mRad divergence, or a CNI module with a 5mm near round beam, and 1mRad divergence - i think the CNI, but you lot are the experts....

comments please, on all aspects!

[swamidog]

you may have a problem fitting a 5mm beam onto your galvo mirrors.

Hello there,

im fairly new around here, however have greatly enjoyed reading up on a lot of the threads.

to cut to the chase so to speak, im fairly new to the laser side of things, but have 20 odd years experience in the lighting industry. Last summer, i purchased a pair of RGB projectors with pangolin quickshow running things, with the purpose of providing some beam shows along with some of the lighting rigs i put in for dance events

the projectors are matched pair, outputting roughly 3.8w total, with a combination of 445, 532 and 650nm.

Whilst fairly well balanced in terms of white, i don't like the beam characteristics of the 650nm diodes, and my reading suggests that smaller 637nm modules would make a better bet. I am also intending on re-boxing the lasers as the current cases are small and dont allow a good layout, and i would also separate driving electronics and optics to minimise dirt build up etc.

So, goldenstar laser seems to be a good resource for parts, and they seem to have 2 options on the 637nm module. I am looking at 600mw, hoping that it will give same apparent brightness as the 1.5 - 2W 650nm modules currently in place.

so, am i better off with a laserwave module giving a 3.5mm near round beam with a 2mRad divergence, or a CNI module with a 5mm near round beam, and 1mRad divergence - i think the CNI, but you lot are the experts....

comments please, on all aspects!

[csg]

fair point, however i will be looking at new scanners as the generic 20K ones fitted have a nasty habit of overheating. Something along the lines of DT40 pro - i am aware that the larger mirrors will slow the galvo's down, but all i need is a good clean 20K, or less at wise angles.

but, will a 5mm beam with less divergence look better at distance than a 3,5mm one with twice the divergence?

[swamidog]

start by contacting bridge (the owner of laserwave) and verifying those specs. a lot of chinese vendors state <2mrad divergence on all their lasers so that figure doesn't always reflect the actual divergence. bridge (bridge@laser-wave.com) is very responsive and quite helpful.

a 5mm beam with @1mrad will look better in far field, but worse in near field than a 3,5mm with 2mrad.

if you're doing long overhead beams, the CNI will stay sharper longer, but it's also important to take into account the beam characteristics of your other lasers. your shows will always look nicer if the beam characteristics of all the lasers are reasonably matched.

the dtpro40's can be had with mirrors for 5mm beams (7x9X and 7x12Y) with the following claimed specs (36K-38Kpps ILDA at 8° 50Kpps ILDA at 6°). i run dt40w's in my projector. i think the dt line of galvos is a good balance of price and performance.

fair point, however i will be looking at new scanners as the generic 20K ones fitted have a nasty habit of overheating. Something along the lines of DT40 pro - i am aware that the larger mirrors will slow the galvo's down, but all i need is a good clean 20K, or less at wise angles.


but, will a 5mm beam with less divergence look better at distance than a 3,5mm one with twice the divergence?

[edison]

A good option would be DT30,s with 7x12mm mirrors since you want 20kpps only so plenty of head room. And they are a good deal for what you have to pay

[norty303]

I'd agree with Edison. I use DT30 with the larger mirrors in all my projectors and for beam shows at ~20k they are more than adequate and significantly cheaper than the 40's

[csg]

thats interesting, and im all for saving some money. Are the DT30's as likely to stay happy if im working at some very wide angles as the 40's - i know there are DT40 wide units, but i would like to be able to work at say 50 degrees at reduced power in smaller venues. I realise that i am never going to get 20K at these angles, but my current scanners have a nasty habit of loosing position and giving me "spaghetti" if i push the angle.

After 6 months, both projectors have paid for themselves, so im more than happy to make some investment into them, but only if the upgrades are worthwhile.

[norty303]

As they come out of the box, I run mine at full width, unless I have to thin the zone for any reason. No idea what that angle is I'm afraid though.
I've had cheap scanners in the past and I've never seen the DT30's 'break down' and go all curly like the cheap ones do, especially not at 18k

[absolom7691]

but my current scanners have a nasty habit of loosing position and giving me "spaghetti" if i push the angle.

That's your poly switch triggering. I'll second what Norty said. I just replaced a set of the cheap PT-40K galvos with some DT-40pros. I can't give exact angles because I have not measured but I can say that I can run my DTs at twice the angle at which my other cheap galvos' poly swtich triggered. My DTs get warm and needed good heat dispersion, but they do the job. As far as inexpensive scanners go, you absolutely cannot go wrong with DT scanners. If you have a bit more to spend, I know a lot of people love the wide scan angle of the EMS-4000s but they are a significant jump in price.