Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

Gun-safe 150-300mW lasers

Joined
May 14, 2013
Messages
3,798
Likes
505
Points
0
To turn on accessories, yes. Do you own? How do you do it?

EDIT: I'm not leaving out the possibility of using the activation pad. But if the laser I'm aiming to get caps at 50mW, a 15% decease from that may not be worth it. Hard to tell at this point but I'm not taking that option off the table.

What do you think about my last post though? Am I on the right track?
No really I don't think you are. We're not talking about a flashlight here, you can't be leaving it on for minutes at a time, and if you did you have to be careful where your pointing it. If you do want to be able to have it on for up to 4 or 5 minutes at a time instead of 30 - 60 seconds then you will need something larger and under 100mW. For example look at my 82mW 520nm here:
http://laserpointerforums.com/f45/pl520-build-1-3-lasers-very-pic-heavy-88336.html#top
Again there are photos for scale, in fact there is one of it next to the C6, see how much larger it is. I wont run it more than 5 minutes and prefer to keep to 4 or less. If you decide on something really powerful for beam visibility then you will probably end up with about a 30 second duty cycle. This is why I would want the pressure pad, for quick and easy access to switch it on/off, you can switch it on/off with your left hand without looking at it, or you could possibly place it next to the trigger.

Alan
 

Rifter

New member
Joined
May 8, 2014
Messages
572
Likes
20
Points
0
What I meant is you need 200mW of 445nm to get a beam similar to 30mW of 520nm. The actual dot will be much less bright, because Rayleigh scattering is inversely proportional to the 4th power of the wavelength.
When the beam is too bright in relation to the dot it's much harder to be sure where the dot is, and in your case much easier for the target to notice where you are.

Blur depends on your eyes, but it's always worse with blue/violet. At 10m 445nm looks slightly blurry to me. At 200m it's too blurry to be useful for spotting a target.

473nm is DPSS - easy to break and highly unstable. Same goes for 532nm. There are some "high WL" blue diodes, but they are hard to find at low powers and very expensive.

I really think 520m is the best way to go here.
I agree 100%, having just built a pl520 80mw laser the divergence on this thing is almost unbelievable it would be perfect for a targeting laser.
 

Atomicrox

Well-known member
Joined
Jun 22, 2011
Messages
2,431
Likes
321
Points
83
Thanks for your continuing to help out Atomic.

I'm totally getting what you're saying, but it's hard for me to relate because I don't own a 520. Could you maybe speak in terms of 532? That is, how many mW of 445 would I need to equal the beam visibility of say a 50mW 532? Also I think ultimately at this point I just want at least a visible beam. Even if a 50mW 445 isn't nearly as visible as a 30mW 520 (this looks like a 30mW 520 right?: Green 30mW laser beam during nightly snowfall - YouTube) as long as you can see a beam, I think I would be happy. Is there a semi clear visible beam at 50mW of 445? 75mW?

As far as the blurriness at 200m goes, that is annoying but I probably won't be using a laser at that distance. I might use it at 100m (125 max) but more than that I'll probably be using a scope. Does it matter how many mWs you're using? What I mean is, would a 200mW 445 look more blurry at 200m than a 50/75mW 445 at 200m? Or is that irrelevant?

I guess the reason I'm shying away from the clear advantages of a 520 is because I already own a 532 and will be purchasing the Surefire X400 ultra with a 532 5mW laser eventually too. And given how a 520 is essentially green, I want some variety hah. I think given how blue stands out less too gives it a very slight tactical advantage as well (so it's not all bad hah). And blue is my favorite colour hah.

It sounds like getting one of those 473s is pretty hard and out of the question then. Was worth a shot.
532nm is almost the same as 520nm visibility wise. The color is different, more of a minty green with no yellow hue.

I don't have a bunch of lasers at each color and power to be able to compare. I said 30mW 520nm and 200mW 445nm because I actually have those.

Blur doesn't seem to depend on power but I'm not 100% sure.

TBH I'm getting tired of repeating the same things. Now it's time for you to go ahead and do some research.
 
Joined
Jul 13, 2014
Messages
35
Likes
3
Points
0
Sorry I haven't replied in a while. As I said I was out of the country and really didn't have great wifi access. I'm back now though!

No really I don't think you are. We're not talking about a flashlight here, you can't be leaving it on for minutes at a time, and if you did you have to be careful where your pointing it. If you do want to be able to have it on for up to 4 or 5 minutes at a time instead of 30 - 60 seconds then you will need something larger and under 100mW. For example look at my 82mW 520nm here:
http://laserpointerforums.com/f45/pl520-build-1-3-lasers-very-pic-heavy-88336.html#top
Again there are photos for scale, in fact there is one of it next to the C6, see how much larger it is. I wont run it more than 5 minutes and prefer to keep to 4 or less. If you decide on something really powerful for beam visibility then you will probably end up with about a 30 second duty cycle. This is why I would want the pressure pad, for quick and easy access to switch it on/off, you can switch it on/off with your left hand without looking at it, or you could possibly place it next to the trigger.

Alan
Oka, that's a big misunderstanding I had I guess. I had no idea it could only be turned on for fairly brief moments. As I've been thinking about it more I have no problem going under 100mW. I'm actually thinking closer to 50mW is just fine... maybe even 20. It seems having a visible beam would create just too many problems that are not feasible as an accessory on an AR. But I understand now why you were so insistent on the pressure pad. When you understand how you can't keep it on for long periods the pressure pad becomes a must! But since I'm wanting a tactical laser that I can keep on for numerous minutes I guess I won't need the pressure pad still, but maybe not; It's still not a bad idea.

Also thanks for the link. The comparison pictures are real helpful as the larger host is far too long to use as an attachment. For a 50mW of 445 what would be the safe amount of time to leave it on at once? For a 20mW? And what would be the consequences? For example, would I destroy the battery?

Thanks as always for your considerable help!
 
Joined
Jul 13, 2014
Messages
35
Likes
3
Points
0
I agree 100%, having just built a pl520 80mw laser the divergence on this thing is almost unbelievable it would be perfect for a targeting laser.
Thanks for your input!

532nm is almost the same as 520nm visibility wise. The color is different, more of a minty green with no yellow hue.

I don't have a bunch of lasers at each color and power to be able to compare. I said 30mW 520nm and 200mW 445nm because I actually have those.

Blur doesn't seem to depend on power but I'm not 100% sure.

TBH I'm getting tired of repeating the same things. Now it's time for you to go ahead and do some research.
Again, thanks for your input as well. I'm still getting tons of new information so I really appreciate the help.

And the thing is, this just IS part of my research. How else better to research something than asking people with years of experience? If you find it frustrating I'll refrain from asking you any questions directly. But presumably others don't feel this way and are still giving me considerable help and knowledge. And if they do feel that way, than I'm grateful that they are giving their assistance anyway!
 

Atomicrox

Well-known member
Joined
Jun 22, 2011
Messages
2,431
Likes
321
Points
83
I don't mind helping, sorry if it sounded rude. It's just that it seems like you want us to tell you what you want to hear - viz. go with a high power 445nm.

The safe time to leave it on (duty cycle) depends mostly on the heatsink - the bigger it is and the lower the laser power the longer you can leave it on. Same is valid for the battery - the bigger the better - but usually the diode will heat up faster than the battery will deplete.

Maybe you should buy a not-so-expensive 520nm/445nm laser and test it.
 
Joined
Jul 13, 2014
Messages
35
Likes
3
Points
0
I don't mind helping, sorry if it sounded rude. It's just that it seems like you want us to tell you what you want to hear - viz. go with a high power 445nm.

The safe time to leave it on (duty cycle) depends mostly on the heatsink - the bigger it is and the lower the laser power the longer you can leave it on. Same is valid for the battery - the bigger the better - but usually the diode will heat up faster than the battery will deplete.

Maybe you should buy a not-so-expensive 520nm/445nm laser and test it.
I understand where you're coming from. To be honest, I do want you to tell me to go with the high powered 445! hah. But more than that, I want you to tell me what's realistic like I know you have been. It's unfortunate it's just not realistic for what I want, but that's life. So I'm thinking more on the 20-50mW range and am just going to forget about the visible beam aspect.

I think that's a good idea though with possibly buying a test one that's cheaper. How do you measure how long you can leave it on? I'm assuming it doesn't have a warning light or something that goes off. If a 50mW 445 had a fairly large heatsink (assuming it would fit in the host) how long do you think you could keep it on? What about a 20mW of the same thing.

I'm looking up heatsinks right now
 
Joined
May 25, 2013
Messages
542
Likes
32
Points
0
just an idea, you should look at Blords 501b's (top of the buy/sell/trade section) - $90 bucks for a 1W+ 445nm with a duty cycle of 60 Seconds on 60 seconds off maybe even longer, and if you asked him, he may try extra driver heatsinking and under drive it for you to output around 250mW while using 3 element lens , the advantages to this would be that ,
*you would have longer duty cycles(possibly 2-3 min or longer)
*1 inch mounting (heaps of cheap dovetail/weaver 1inch mounts around)
*cheap pressure switches around $2-5 (and you can swap from clickie to presure switch)
*using 3 element lens changes the typical bar shape dot from this diode to a nicer dot ( with power losses compared to G2 lens)
*cheap for a pre built laser with high quality
* Awsome Seller, really looks after his customers!

so i can say all that stuff but it still brings us to the question.... how will we zero this in?

anyway ill chime back in later recomending the same thing in different words,
Haha Good Luck!
 
Last edited:

Atomicrox

Well-known member
Joined
Jun 22, 2011
Messages
2,431
Likes
321
Points
83
The 501B from Blord is a good idea, but I urge you to ask him for a single mode diode. If you're set on 450nm I suggest this diode: https://sites.google.com/site/dtrlpf/home/diodes/450nm-pl450-diodes

I'll still be blurry and have "too much beam versus dot", but at least it will have a nice small round dot.

In his copper heatsink underdriven to 50mW I'd guess the laser could run for 10's of minutes without overheating. But better ask Blord :p

The rule of thumb for duty cycle is simple - if it's getting warm turn it off. I don't think there's an easy formula to calculate it.
 
Joined
Jul 13, 2014
Messages
35
Likes
3
Points
0
just an idea, you should look at Blords 501b's (top of the buy/sell/trade section) - $90 bucks for a 1W+ 445nm with a duty cycle of 60 Seconds on 60 seconds off maybe even longer, and if you asked him, he may try extra driver heatsinking and under drive it for you to output around 250mW while using 3 element lens , the advantages to this would be that ,
*you would have longer duty cycles(possibly 2-3 min or longer)
*1 inch mounting (heaps of cheap dovetail/weaver 1inch mounts around)
*cheap pressure switches around $2-5 (and you can swap from clickie to presure switch)
*using 3 element lens changes the typical bar shape dot from this diode to a nicer dot ( with power losses compared to G2 lens)
*cheap for a pre built laser with high quality
* Awsome Seller, really looks after his customers!

so i can say all that stuff but it still brings us to the question.... how will we zero this in?

anyway ill chime back in later recomending the same thing in different words,
Haha Good Luck!
Good stuff DorDie. I appreciate the recommendation. I'll ping him about it and see what he says.

However, I'm still thinking along the lines of 20-50mW now, so 250mW just might be too extreme for me hah. I've kind of given up on the whole visible beam idea due to the fact that I want to be able to keep it on for a considerable amount of time relative to "laser time". What do you mean by "1 inch mounting"? Are you saying it would take up 2 slots (about 1 inches worth) on a picatinny or universal rail?

The other thing is, if I'm going to be using this tactically, I can't always been wearing protective eye gear. Therefore, the risk of reflecting a 250mW laser back at my high produces a far greater danger than reflecting a 20-50mW laser back in my eye.

What I've been trying to research is what you keep bring up: how will I zero it in. You are absolutely right, that is a hard factor that needs to be figured out. I'm looking into Surefire's X400 Ultra Green laser to see how they zero in their laser. I've also looked at one of crimson traces laser mounts. From there maybe I can figure out a workable solution.

Sorry it took me a while to respond to this. I've usually been getting e-mails notifying me when someone makes a comment but I never did for these last two. :undecided:
 
Joined
Jul 13, 2014
Messages
35
Likes
3
Points
0
The 501B from Blord is a good idea, but I urge you to ask him for a single mode diode. If you're set on 450nm I suggest this diode: https://sites.google.com/site/dtrlpf/home/diodes/450nm-pl450-diodes

I'll still be blurry and have "too much beam versus dot", but at least it will have a nice small round dot.

In his copper heatsink underdriven to 50mW I'd guess the laser could run for 10's of minutes without overheating. But better ask Blord :p

The rule of thumb for duty cycle is simple - if it's getting warm turn it off. I don't think there's an easy formula to calculate it.
I agree with you Atomic, from what I've heard from most people the reliability and stability of a single mode diode is the way to go. However, I was under the impression that a 50mW 450 would have fairly little beam visibility and a 20mW 450 wouldn't have any. So when you say it will still be blurry are you referring to the dot itself? If it's the beam you're talking about, than perhaps a 20mW may be the way to go to get rid of that blurriness. And then the duty cycle might increase in that way.

Thanks for the tips on overheating. Because of that that's something I'm now starting to keep track of on my 100mW 532.
 

Atomicrox

Well-known member
Joined
Jun 22, 2011
Messages
2,431
Likes
321
Points
83
The dot, yes. I don't notice blurriness very much on beams.

Around 30mW of 462nm still makes a visible beam, but just barely. I don't have a <100mW 445nm here to test.
 




Top