This isnt anything truely special, but i thought i would post what i discovered anyways... if there is something you didnt know, they my point is made ;)

Anyways, My cats *LOVE* my lazer pointer, but it since died. Those little watch batteries arn't made for such abuse. After discovering that the batteries cost more than the pointer itself, i ideded to correct the problem and use cheap "AA" batties instead.

The problem is my pointer what "encased" never to be fussed with again. It was about 1/4" in diameter and very hard to see and get anything. So here is what i did and learned about them:

    [*]First I unscrewed the from cap, and found the lense had an adjustment 'slot' across its brace face. This is for setting the focal point. I unscrewed it off, and saved the plastic lens hoping i would be able to remove the eletronics from the top. This is not the case.
    [*]Seeing no other way, i hack-sawed the back half off (battery section), careful not to damage the center spring that contacts the batteries center cathode face. Once done, it was no effor at all to remove a plastic plug holding everything in place and getting to the electronics.
    [*]Studying the device, it was a very simple series circuit. The outside casing was the positive 3-4.5V, since this is the larger face on the watch batteries. The center spring was the cathode contact, or ground. The casing touched the brass lens fitting which held a spring, lense, and adjustable screw for forcal length. The other side was soldered to the Anode of the Lazer Diode.
    [*]The lazer diode looked smaller than i expeced. Its really the lense that makes it act like a lazer. The cathode connected to a circuit board, thru a SMT resistor, a cheapy push button switch, and to the cathode spring that would touch the batteries and complete the circuit.
    [*]I then took an old Radio-shack '3V' hobbiest battery containter (plastic box for two AA's in series, and two wires), and soldered the positive to the brass fitting where the lense sits. and the negative to the cathode spring.
    [*]Repackaged it up and with some duct-tape, The battery pack, and the half Lazer-Pointer was made into something that was eazily hand held. And now has a far greater life span, with cheaper and ez to replace batteries.


    I know this isnt anything great. More, ho-hum, stuff. But for any new guys with a dead lazer pointer.. this is a little project you can do in 30 min.

    Just be sure not to knock the diod or the board of the Lazer diode. If the orientation of the lense to the diode changes, you will need to re-focus the lense to create a solid 'dot'. (I discovered this as it was acting more like a flash light when i first put it together). Little trial and error adjustments, and im back in business.


    Next to get a mirror, two servo motors, and a PIC chip ;)
    :alright:
    NaN
Posted on 2003-04-06 21:57:42 by NaN
Here is a clearer picture of the lazer pointer... and what to do yourself.. (Alot of the above is for knowledge only ;) )
Posted on 2003-04-06 22:41:58 by NaN
And here is the replacement...
Posted on 2003-04-06 22:42:58 by NaN

"laser diode radiates like a led" - does it mean a normal led is ok too?

I thought that the laser diode was outputting a straight ray, and the len could only make it become worse (i.e. expand with distance).
Posted on 2003-04-07 02:52:12 by Maverick
Maverick,

I share your thoughts.. however i dont have a clear answer. It does radiate in all directions. But its very small and bright. I didnt really get my eyes too close (if you know what i mean). But I found that the lense it came with focuses it to a long narrow dot. If i screwed it too loose, i get a flashlight like beam. If i screwed it too thight, i get the same.. Only at one mid focal point, i get a narrow intense beam. I later had to adjust it again as it was still spreading a bit at LONG distances. Very slight turn of the screw, and presto its the same dot at both near and far.

I dont know any LED that is that bright at 30 feet away. So i have to assume its some "LAZER" "DIODE" (the latter part seems appearent anyway).

:NaN:
Posted on 2003-04-07 16:09:41 by NaN
To be honest, i always thought there was two reflectors: a partial one at the emmitting end, and a full reflector at the back end. Both spaces to pi/2 multiples of the wavelength. But i guess im wrong here. (or this is achieved in the very small diode head at 2 or 3 wavelengths ~ and only appears to radiate in all directions from leakage).

:NaN:
Posted on 2003-04-07 16:12:58 by NaN
NaN, I thought reverse engineering was against the rules of this board :rolleyes:
also, what's with the funky "lazer" spelling? personal preference, or canadian weirdness?
Posted on 2003-04-07 16:18:37 by f0dder

NaN, I thought reverse engineering was against the rules of this board :rolleyes:


Beware ! Don't forget he is building a lazer ! :cool:
Posted on 2003-04-07 16:27:14 by JCP
Reverse Engineering applies to software, simply because i cant say or type "COPY" and presto have another modified lazer pointer. If this was possible, i could get carried away and eventually deminish the quality of the origional laZer pointer due to my overwelming supply of new and enhanced laZer pointers (which i could hand out to all my friends and pet owners alike, with no cost to me).

There is no software in a laZer pointer, so break out the hack-saws and duct-tape! :rolleyes:

As for the read.. ya, i was burnt last night.. I just typed and posted ;) . I dont try for any gramatical award around here (if you havent noticed by now).

:NaN:
Posted on 2003-04-07 16:59:06 by NaN
The lazer diode must emminate a narrow band of frequencies that are somewhat coherant and the lens is tuned (curved) to this range so it can focus the beam.

An LED would have far less coherant light.

Had plans for a maser once (MASER>>>MICROWAVE AMPLIFICATION BY STIMULATED EMMISSION OF RADIATION) that could burn through 5 razor blades in 500 microseconds.

Never built it though.
Posted on 2003-04-07 17:17:49 by IwasTitan
Hi NaN :alright:
(or this is achieved in the very small diode head at 2 or 3 wavelengths ~ and only appears to radiate in all directions from leakage).
I'd bet my coin on that too. :)




Hi IwasTitan, you wrote:
Had plans for a maser once (MASER>>>MICROWAVE AMPLIFICATION BY STIMULATED EMMISSION OF RADIATION) that could burn through 5 razor blades in 500 microseconds.

Never built it though.
And the world is grateful to you for that. ;)
Posted on 2003-04-07 17:48:54 by Maverick
LoL,

Ya, 1/2 second to punch a hole in 5 consecutive razor blades... 1/2 to set your bathroom wall on fire ;)

:alright:
NaN
Posted on 2003-04-07 23:07:09 by NaN

LoL,

Ya, 1/2 second to punch a hole in 5 consecutive razor blades... 1/2 to set your bathroom wall on fire ;)

:alright:
NaN


1/2 second would be 500 millisecond. Not sure if i had the timing right because the plan was in a book i had many moons ago. Could have been miiliseconds but i'm pretty sure it was something like 1, 2 or 3 .....500 micro second bursts.

I didn't do the project because GE didn't know what the hell i was talking about when i wanted to order a helix flash tube.

If i couldn't get that.... what the hell was the use in trying to get the rubidium oxide for the ruby crystal.
Posted on 2003-04-07 23:21:27 by IwasTitan
Some True Stories.

I used to work with a physicist who dealt with lasers. We used em to cut resistors up to value, and had so many hangin out we needed him just to keep em running. (He was so good at his job, he got it down to just a few hours of maintenance a week, he'd j*rk off the other 36 hours he was there).

Anyway, at his previous job they made some really really powerful lasers. They finally got one working, a biggie with some hundreds of watts of continuos output. They had it aimed at a square foot of battle ship armor they kept around as a target. Being 6 inches thick of armor, by its mere weight it could absorb a lot of power and not even get slightly warm.

Of course, it was the end of the day when they got it working, so they left it on, turned out the lights, and went home to let it burn itself in overnight.

Too bad no one told the cleaning crew, who moved the chair to clean the floor.

While no one was injured (it wasn't THAT powerful), a very neat clean hole was burned in the lab wall..

And the office wall next to it. And the meeting room. And the cafeteria.

The brick exterior wall finally held it inside.

I lost touch with him after I left the place, but I did see him on TV a few years later. He was assisting some guy selling car polish, and the hook was you could even hit the car with a laser and it wouldn't damage the finish.

Too bad the car polish guy didn't understand a laser is really powerful, it cost him a brand new shirt just before taping. They were laughing at it during the demo.
Posted on 2003-04-07 23:43:20 by Ernie
IwasTitan, I have plans for a laser if you want to build one.
IIRC, Clorine-Iodide laser -- it's from an old Scientific American magazine. :)
Posted on 2003-04-07 23:50:43 by bitRAKE

IwasTitan, I have plans for a laser if you want to build one.
IIRC, Clorine-Iodide laser -- it's from an old Scientific American magazine. :)

I'm setting my time for another project this summer but it would be nice to see the plans.


Is that a luquid type lazer?
Posted on 2003-04-08 00:10:10 by IwasTitan

Is that a luquid type lazer?
Green-yellow gas - emmits mainly two frenquencies of light. Please, note it has been over ten years since I read the plans. I'll dig the plans out of box out for scanning - it's always fun going through those old magazines. I have some old popular electronics magazines from the 70's, too!
Posted on 2003-04-08 00:49:16 by bitRAKE

Reverse Engineering applies to software, simply because i cant say or type "COPY" and presto have another modified lazer pointer. If this was possible, i could get carried away and eventually deminish the quality of the origional laZer pointer due to my overwelming supply of new and enhanced laZer pointers (which i could hand out to all my friends and pet owners alike, with no cost to me).

You seem to be confusing Reverse Engineering and piracy there. I'm pretty sure taking apart an electronic device and studying how it's built qualifies as Reverse Engineering. Whether it's illegal is another question to which I don't know the answer, and there's probably a lot less attention on HW RE (of this magnitude) than SW RE. And it's fun to read, so I think it'd be a shame if it's against the rules of the board.

But it's RE nonetheless.
Posted on 2003-04-08 02:01:12 by f0dder
heh NaN can you post a scan of what it looks like after the modification?
Posted on 2003-07-02 14:21:05 by EEDOK
Reverse Engineering

To do enginering in reverse, thus to dismantle something, pick apart, open up the radio and unwelding the components, (run the car engine backwards, toxic gases in, gasoline out ;))

Afaik only RE in SW are/is illegal, I've heard of pirate spare parts (spare parts for e.g. cars that hasn't been made by some authorized manufacturer), I think guarantee can be voided if using pirated spare parts.

Btw, RE anthing that has lazer on it is dangerous, let say you somehow get the lazer to go on by mistake, if you're unfortain you might damage you seeing. That's why one shouldn't open upthings like CD players (/me no saint, me not saint, me wares glasses (not due to that I think :P )).

bitRAKE
it's always fun going through those old magazines.

Yeah, I saw in an old magazine, the personal "Super computer", ammazing 450 Mhz, 128 MB and a hold on thight 20 GB disk... I wonder if one can run the latest windos on it?
Posted on 2003-07-03 06:24:03 by scientica