Help purchasing a Red laser pointer

[alanbrito]

I figured you guys must have some good experience. I have posted in these forums in the past (built my own Blu-Ray laser direct laser write lithography setup for dirt cheap, rivaling system costing upwards of $100k).

I am currently looking at purchasing a mid power red laser (pointer). I need something above 10 mW, preferably around 650 nm and with low divergence and relatively high stability. If possible it would be great if it has a toggle on off button.

A bit of info on what I am trying to do: I am trying to look at the diffraction pattern of a novel diffraction grating structure that has very dense features, thus, it requires higher power in order to be able to see diffraction spots well. That, while being illuminated by a focused green laser to introduce heat into the grating samples. In essence, it is a pump-probe setup. I have a HeNe laser (633 nm, 0.4 mW) that just is too weak for it. 650 nm would work best, since I have a red 650-40 type filter before my detector. Beam divergence should be low, as for the beam to not spread too much after about 30-40 cm. Good stability would be great, as I am measuring time dependent dynamic changes.

Any good places too look online? Wicked lasers has their Nano red lasers, but they are ridiculously over priced. They do have high quality stuff (used an Arctic 1 or 2W laser before that was very good), but they are generally too pricey for what we want to do. My boss wants me to get a cheap one, of course, but getting something that is cheap/high power/high stability/low divergence is hard.

 

[FlutterPie]

So many people come here and ask these questions all the time. My advice is check out o-like and rayfoss. If you are looking to spend a little more check out jetlasers and dragonlasers. There are also people on the forum that sell lasers like you are asking. But currently I can't remember the names.

 

[Tmack]

Sflasers 200 mw 650nm 45$ one of my most stable lasers. Overspec as well. Contact thejoker301

 

[NO4H99]

I'd stick with Sci-Fi lasers, if 200mw is not too powerful. At 30-40cm, divergence should not be an issue with any focusable laser. How long do the duty cycles need to be? Maybe a lab laser would suit you purposes better than a handheld?

 

[SerpantSlayer]

Divergence of red woudnt be as good as green. Try a Mitsubishi 500mW 635nm laser diode
.

 

[NO4H99]

Divergence of red woudnt be as good as green. Try a Mitsubishi 500mW 635nm laser diode
.

Multi-mode 635 diodes have just about the wort possible divergence. At less than 15 inches, a 650 will work fine.

 

[SerpantSlayer]

True idk whats more important to him good divergence or high power.

 

[NO4H99]

He said that good divergence, over 10mw, and good stability was needed. I'm fairly sure that a 635 is not what he's looking for.

 

[SerpantSlayer]

Didnt see the 10 mW part.

 

[PhaserII]

Try looking at those Ebay 301 lasers in 650nm I have 2 with a consistant 265mw of power.

Its a momentary switch but a little imagination can easily get around that!

Best part they are like 20-40 dollars ( or less). Just a thought . divergence is very good
good luck!!

 

[ZRaffleticket]

Since when is 200mW not high powered?

Gotta ask-- how long do you need it to run?

Assuming he needs power stability too, at his range he honestly wouldn't need anything over 50mW. A well heatsinked host with a LPC running at 50mW is more than enough. I'm sure there'd be someone on the forum willing to make a C6 at that range.

 

[NO4H99]

Sounds like a labby at 50 or so mw should work perfectly - could heatsink it for a permanent duty cycle.

 

[alanbrito]

Holy crap, thanks so much for the replies guys. I am reading through them and will try to reply.

So many people come here and ask these questions all the time. My advice is check out o-like and rayfoss. If you are
looking to spend a little more check out jetlasers and dragonlasers. There are also people on the forum that sell lasers like you are asking. But currently I can't remember the names.

Awesome. I did run into the o-like products but I will check the rest out.

Sflasers 200 mw 650nm 45$ one of my most stable lasers. Overspec as well. Contact thejoker301

That seems really good. I will double check with them. 200 mW will likely be more than plenty, even 50 mW would work just fine. I can probably tune the power with a polarizer/halfwave plate/polarizing beam splitter setup.

I'd stick with Sci-Fi lasers, if 200mw is not too powerful. At 30-40cm, divergence should not be an issue with any focusable laser. How long do the duty cycles need to be? Maybe a lab laser would suit you purposes better than a handheld?

a lab laser, if by that you mean the mounted diode types with heatsink and all that... we just want a quick, cheap solution. so probably gonna stick to either torch type or handhelds.

Divergence of red woudnt be as good as green. Try a Mitsubishi 500mW 635nm laser diode
.

That would be great, but wouldn't need that much power.

Multi-mode 635 diodes have just about the wort possible divergence. At less than 15 inches, a 650 will work fine.

Correct. Multi mode will not work. I am interested also in beam quality, having an M^2 value that is close to 1 would be ideal. Multi mode beams are never close to M^2=1.

True idk whats more important to him good divergence or high power.

He said that good divergence, over 10mw, and good stability was needed. I'm fairly sure that a 635 is not what he's looking for.

That's correct.

Didnt see the 10 mW part.

Try looking at those Ebay 301 lasers in 650nm I have 2 with a consistant 265mw of power.

Its a momentary switch but a little imagination can easily get around that!

Best part they are like 20-40 dollars ( or less). Just a thought . divergence is very good
good luck!!

Will try that as well.

Since when is 200mW not high powered?

Gotta ask-- how long do you need it to run?

Assuming he needs power stability too, at his range he honestly wouldn't need anything over 50mW. A well heatsinked host with a LPC running at 50mW is more than enough. I'm sure there'd be someone on the forum willing to make a C6 at that range.

Yeah, 50 mW I assume is sufficient. Thing is, since the diffraction patterns I am studying have such high density features, the power gets split up into multiple spots, not just the typical diffraction grating spots. Stability would be nice as well. I have experience hot wiring Blu-ray diodes to current sources, but I have no idea what your last sentence meant. Edit: scratch that, just reap up on LPCs and the C6 host.

Sounds like a labby at 50 or so mw should work perfectly - could heatsink it for a permanent duty cycle.

What is a labby? And for duty cycle, I will probably keep the laser running continuously on CW mode.

 

[Tmack]

Look at aixiz. Com they have red lab style lasers that have a cooling fan for continuous use. 180mw of 638. Although the divergence won't be great it's fully tunable to run at lower power.

 

[alanbrito]

Look at aixiz. Com they have red lab style lasers that have a cooling fan for continuous use. 180mw of 638. Although the divergence won't be great it's fully tunable to run at lower power.

Hm. pretty sure that is where I purchased my old BluRay parts from a few years ago. Thanks!

 

[NO4H99]

A labby is a lab style unit. You could probably get one that you could adjust the power and have a continuous duty cycle.

Also, the lower the power, the longer the duty cycle. If a handheld is what you want, I'd definitely get the 200mw SFCR from Sci-Fi. Only problem is that it would have a duty cycle of less than two minutes, which is why I suggested a lab style.