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



Laser Pointer Store

150mW DX green pen

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
So. I needed some green cheapo for star pointing etc.
I knew this laser model is lower quality, and big assembly and power output difference between every piece of this model. So I bought three of them, prepared to choose best one, and sell these two remaining.



Introdution, packaging:
It came in dark paper boxes. Few months ago, I had one 50mW packed in nice comfort "semish" box, and to compare from what I remembrer, the housing of laser itself was also better quality - heavier, better screw thread, everything a little bit better quality, while these three are really cheaper in material machining. It has also the problem about batteries clacking. One of them is ok so far, while two of them are horrible about it. Beam is not disappearing by this issue, but I can see some power fluctuations according to bad contact of batteries and sometimas bad contact from the "power button". It´s really cheap, nothing for serious work.

The beam:
Now I can talk about all of them at once - they are pretty same.
Could not measure really, but the beam diameter at aperture is nice and thin. It is about 1.5mm or less.
Next thing to say is, that it works perfectly in "TEM00" all the time.
On the opposite, there is awful "halo" around the lens.
I took a photo of beam nearly hitting a paper.

Tried to clean all, helped a bit, but still not big deal.
Divergence was totally out of usable range. I mean something like class "F" or worse. Maybe my grandmother could do it better. The beam was visibly expanding, blurry and could not reach buildings more than 1km far.
Brrrr ugly ugly. What crap have I bought?

Now some Diy and repairing notes you can jump over:
So I took it to my work to measure power consumption and so on. It was 610, 590 and 490mA for the "weakest" one. The ability to burn on first look was similar.
I was not happy with the result, and finally tried to disassemble one of them. I was sure that I´m throwing my money right in a bin by disassebly, because when I tried it on my old 50mW one, everything has been glued so much. It resulted as total destruction of LD :) With acknowledge I am going to do the same, I did it anyway. There came a huge breakpoint. The GOD just enlightened me, and gave me better units to disassemble.
It was damn easy. I found screwable lens inside, so it was only matter of good distance between the LD and the lens, which I could set by screwing the part of body with lens mounted on it.

Here you can see internals:



Still not big deal, but the resistor is a half Watt, almost unable to get burned :) . I put some paper between it and the housing, because it´s not good to touch each other...

Back to lens - It was totally screwed on, so I tried to unscrew a little bit, which resulted as even worse divergence. Ok, I took some sand paper, and skived the lens body to make it screw deeper on the rest of LD body(heatsink).
It came better! So I did it again and again, looking how it gets better, till it got worse again :) WTF? I did it too much. So I disassembled these two remaining units, skived and combined lens till I got best results from all of them. There is some minor difference between beams of these units, but It´s much much better, able to shoot far buildings as it´s supposed to be like this typically :)
Still - it has crappy lens, so no matter how I set it, the beam is expanding anyway and it has not good divergence.
I also tried to potmod this unit, with no better result. For these who wants to potmod - guys, check your current, My home multimeter is broken, so I could not, which resulted as huge overcurrent of the circuit, extreme heating and burning my thumb from the click button! I was lucky that Driver, Diode, and also bateries are still OK.

Here is the picture of laser "dot" without any lens:




Burning abilities:
I bought Alcalines and NiMH GP AAA 1000mAh Accus. They do pretty the same, but Accus can last longer to supply the unit by plenty of current.
These units can pop some baloons from up to 2m, and cut a tape slowly, but cannot light a match. I tried to paint it black, which resulted as "not enaugh". I can smoke them, but I cannot burn them.



Overall:
For these, who don´t want to buy more units to choose from them, and doing some DIY upgrades on it, It is not worth. It´s damn bad quality. I don´t know why shoud I be happy with it, even after tuning action, but hopefully it will work for me some time, till I acquire some money for the REAL BURNER with good quality (CNI or so...)
Anyway I thing all three are still not good enaug, and I´ll propably sell them all. The best one is only good for short range beamshots...


 
Last edited:

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
I took it to my work, cleaned carefully with isopropylacohol, but nothing good happened, no better result came out.
I also measured the current draw. The strongest one took 610mA, weaker one 590mA and the weakest of them took 490mA With 1.52V Alkaline batteries. It also corresponds with power output when I tried burning. I had a chance to see how big is the dot from far, and It´s really bad, and all three are almost the same. I think these three do not vary in optics so much (as I firstly thought). The optics is glued and not prepared for hand re-focusing (by screwdriver or so), so there is no chance to make them work better for standard user.
I will still edit and make this review full tomorrow, but then I go to sell all of them. I don´t like it.
Once again, cannot recommend this product even for its nice price.

//some updates happened to the first post.
 
Last edited:

randomlugia

New member
Joined
Sep 4, 2008
Messages
1,808
Points
0
Too bad.
That beamshot actually looks like there is something on the diode window, not the lens, just because the green looks so solid. Since you have three, and they're pretty bad anyways, you might as well take one apart and try to clean the fog off the window. Or just harvest parts... The only reason anyone would buy such a laser would be to get the diode.
 

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
Yeah. When I disassembled it, there was no halo. So I assembled it "gradually" till I got the halo. It was the first front lens. No way to get it repaired. Must live with it or sell it.

//just made great editing/rework on my first post.
 

randomlugia

New member
Joined
Sep 4, 2008
Messages
1,808
Points
0
Oh well. Thanks for the update. You said that there are power fluctuations, are you sure that it's because of the bad contacts, and not because the laser is just "warming up"?
 

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
The fluctuations are quick to change, and no matter which time when laseris on - happens sometimes not dependable on power on time, and It changes more, when I play with the push button, or push it harder, so I guess it´s not because of warming up.
I will have to set the pot again at work - accus working on lower voltage, and when it drops from "charged now" to 1.3-1.25V, it looses its "burning" power.
 
Joined
May 2, 2008
Messages
2,031
Points
0
How in the world do you take those pens apart!? lol I have NEVER for the life of me been able to get those things apart, but it seems everyone else does it with such ease :p
 

Eudaimonium

Well-known member
Joined
Feb 5, 2008
Messages
6,311
Points
83
How in the world do you take those pens apart!? lol I have NEVER for the life of me been able to get those things apart, but it seems everyone else does it with such ease :p
The silver cap in the front is holding the entire module, and it's pressfited into the main black tube.
Simply grab hold of the silver cap with vice and work the black tube out with some pliers.

Putting them back together is even simpler.

Silver cap screws into the module threading on the very front of it, for DX modules it's male threading, for O-like it's female threading so the modules are not interchangeable.

Can do without the cap though, if you are not a perfectionist.
- just make up for the difference in module diameter with some aluminum foil.

Take care when the black barrel moves away from the cap-module assembly , you don't wanna lose the little button that's gonna fall out!
 

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
It´s hard dependable which module you have in your hands. The old 50mW one was totally different story, different parts inside, hardly glued, and I DESTROYED it when I tried to disassemble it.

This was different. It all came easily out after I pulled the silver tip out of the housing tube(with the whole module on it) And the next disassembly was hell easy - only unscrew these parts.

If you have bad type, I understand how you feel about it, But it is obviously not problem in your hands :)

P.S.: I use some tube with similar diameter to the housing, put some clothes on the tip of the laser to not get scratched, put the tip in the tube and shake,waggle, moove to the sides gently, till it comes out.
 
Joined
May 2, 2008
Messages
2,031
Points
0
The silver cap in the front is holding the entire module, and it's pressfited into the main black tube.
Simply grab hold of the silver cap with vice and work the black tube out with some pliers.

Putting them back together is even simpler.

Silver cap screws into the module threading on the very front of it, for DX modules it's male threading, for O-like it's female threading so the modules are not interchangeable.

Can do without the cap though, if you are not a perfectionist.
- just make up for the difference in module diameter with some aluminum foil.

Take care when the black barrel moves away from the cap-module assembly , you don't wanna lose the little button that's gonna fall out!
It´s hard dependable which module you have in your hands. The old 50mW one was totally different story, different parts inside, hardly glued, and I DESTROYED it when I tried to disassemble it.

This was different. It all came easily out after I pulled the silver tip out of the housing tube(with the whole module on it) And the next disassembly was hell easy - only unscrew these parts.

If you have bad type, I understand how you feel about it, But it is obviously not problem in your hands :)

P.S.: I use some tube with similar diameter to the housing, put some clothes on the tip of the laser to not get scratched, put the tip in the tube and shake,waggle, moove to the sides gently, till it comes out.
Yes I'm aware of all this :p but whenever I've attempted this myself it seems IMPOSSIBLE to pull it out :undecided:
 

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
Now, this is in your hands! :) How in the world can you NOT to open(pull) the front silver tip??? You just pull or waggle to the sides while pulling, till it slowly comes out!
 
Joined
May 2, 2008
Messages
2,031
Points
0
Now, this is in your hands! :) How in the world can you NOT to open(pull) the front silver tip??? You just pull or waggle to the sides while pulling, till it slowly comes out!
I don't know. It just seems so VERY WELL in there. Will not come out lol.
 

randomlugia

New member
Joined
Sep 4, 2008
Messages
1,808
Points
0
I did it once, with a vice and pliers - it wasn't easy. I got it out, but the cap REALLY scratched up and bent, lol. Have you tried the wooden block method?
 

Crashpc

New member
Joined
May 2, 2010
Messages
105
Points
0
Hey, it takes some time. I like to use another tube as I said, and it takes some force and some time (few minutes of intensive pulling and waggling. Oh my! You can do it! Go,go,go! :D
 




Top