Hello! Looking for 2 definitive lasers

[autofire]

Long time lurker here and now have a little money to spend, already bought Oculus Rift, and a 3D-Printer, so might as well buy a couple lasers. :yh:

I am no stranger to soldering/assembling things so building a laser is not out of the question. What I am looking for is 2 straight up handheld lasers, 1 at 445nm and one green, I am not sure what nm of the most 'pure' green would be. I would like at bare minimum 1000mW. I'd like to spend no more than $600 for the pair, but I'm lenient on price.

I do not want any safety mechanisms, Id like low divergence, I am still uncertain whether I should get adjustable or not. I am not a fan of it because it reminds me too much of a flashlight.

What would your two definitive 445nm and pure green handhelds be? Or what parts do you recommend for purchase in the construction of these lasers?

 

[Sigurthr]

The 445nm will be no issue for handheld form factor and well within your budget. You can make one for probably under $200 these days.

You'll have a lot of trouble finding 1W of green (532nm - the other greens are low power or lab units) for less than $1000, and there is no guarantee it will actually be 1000mW and not closer to 700mW (the average top end for handheld greens). There are 1W 532nm modules and lab units available, but they are certainly not handheld, and they throw off way too much heat to have any appreciable duty cycle if they were to be converted to a portable format.

 

[autofire]

Okay, what would you recommend?

 

[Sigurthr]

It depends on your budget and your needs. What is your intended use for the green laser? IMO anything over 300mW at 532nm gets to be far too bright to enjoy - you just can't view the beam in mid air without eyes hurting and squinting. You'll need googles no matter what power you get over 5mW, but at above 300mW you need goggles on at all times and that takes away a lot of the fun.

I'd say look for a 200-250mW 532nm handheld. It is far more affordable, can have decent run times, and if you set up a safe operating area and procedure you can view the beam safely without needing goggles on.

Laserglow Technologies - Handheld Lasers, Alignment Lasers and Lab / OEM Lasers is a good place for high end well built DPSS units. Find a veteran who is selling components for or a ready made 445/450nm blue, don't buy from a company.

 

[hazerkitten]

But does your 3d printer make titanium parts

Checked out that oculus.. let me know how that goes!

 

[pschlosser]

300mW for the 532nm green is a sane limit to set. There are 400mW (I own one) and greater available as a handheld, but the numbers start going up fast above 300mW.

 

[autofire]

It depends on your budget and your needs. What is your intended use for the green laser?

Well, I want to try data communication with open air laser beams. I want to try to send an image with sstv encoding over a city with a laser beam to a target on the balcony of a friends place. Eventually expanding to tcp/ip and beyond (the goal), with three or more devices connected to it

@hazerkitten - Its open source so I could probably adapt it in one way or another, however mine is closer to printing with graphene right now.

 

[Things]

It would be a good idea to add your location to your profile. In some countries, shining lasers over long distances through the air would require special licensing, so it definitely wouldn't be something you could leave up permanently, especially if it's over a city. Maybe if you lived out in the middle of nowhere you'd get away with it - but we don't know where you live.

 

[Sigurthr]

Cool project. The atmosphere scatters long wavelengths in the visible spectrum less tha short wavelengths. Visibility of course helps with alignment which is a major issue as soon as distance increases past a couple hundred meters or so. I've done voice link communications with 658nm lasers in the past and alignment was always the biggest hurdle.

My advice: grab a 1W 650/658/660nm red module with built in TTL modulation. Find one which can handle say 50kHz TTL input or greater. Build a simple audio PWM generator based on the SG3525 IC (I can send schematic if needed). Set the carrier frequency to just under the maximum TTL input frequency of the module (say 40kHz if it can handle up to 50kHz). Feed your SSTV audio signal in to the SG3525 modulation input. A simple photodiode and RC network as a receiver will perform slope detection and convert the FM modulation of the carrier frequency into an audio signal equivalent to the SG3525's modulation input signal. Feed the output from the receiver in to a simple audio amplifier, and then in to your computer's audio input. Viola'!

Sometimes I wonder if it was working becoming an Extra Class Ham a few years ago, and then someone like you asks a question like this and I realize I am only able to answer the way I did because of that training. Makes me smile. Anyway, good luck!