build a laser pointer?

[PinksteR]

Hi, wanna know if it is simple and possible to make a laser pointer- I need a couple of them for a project and we have a limited budget, so maybe if we can build them ourselfs we can get them cheaper.
Which are the components a laser pointer uses? a common red led and a magnifing glass? i have no idea. if someone knows it would be great

 

[Dr.EM]

You use a laser diode, but i'm almost certain it is cheapest to buy them ready made. You can get them very cheaply if you look around.

 

[audioguru]

My son bought a very nice pen with a polished stainless steel shaft and two bright LEDs in its end, for 6 bucks at the dollar store.
Oh yeah, it has a laser pointer too.

I went to the dollar store the next day and they were sold out. :cry:

If the pen with the LEDs is a bargain without the laser pointer, then surely someone must make just a laser pointer for nearly nuthin. :lol:

 

[kt]

It is better to buy some chinise laser pointer for about 3 euros.
Then you can remove the shield (carefully!) and you'll find
the laser diode and the small PCB where it is soldered.Most of these
diodes have less than 1 mWatt power.You can use this module
for your prototype.Use 2 AA bateries as a power supply.

Good luck

 

[PinksteR]

I know they are cheap, i can get them for 2 bucks here. But we have to get like 4 of them and we are in a VERY short budget.
I still dont get how laser pointers are made. which components they have, etc..

 

[Dean Huster]

Short on budget or not, I sincerely doubt that you can buy the laser diode itself cheaper than you can buy the entire Chinese laser pointer. If your budget is that tight, you'd best be shopping around! Hit the discount stores and gas stations. Around here, they were selling the things for three bucks at the convenience stores. Made it really annoying for teachers because all the students had them and they (the pointers) had to be outlawed in the schools.

Dean

 

[MrMikey83]

So $8 is over budget :?:

 

[PinksteR]

$8 isnt overbudget. But we have 20 bucks for the whole proyect and it has a lot of other components.
As im using a phototransistor (l51p3c) i think im going to get some infrared emitting leds (L53 series) that are spectrally matched to those phototransitors and are much cheaper than the laser pointers, about 0.50 each. The problem is that im not going to have as much range i had with the laser pointer.

 

[DirtyLude]

Those laser pointers are basicly a laser diode a resistor and some cheap plastic optics. That's it. I can pretty much guarantee you can't get the parts cheaper than $2.00. Anything you can buy in single quantities is meant to be much higher quality than those pointers. You can check out the laser diodes on Digikey, the cheapest I saw was $9.00 and that is without optics or a driver (the good laser diodes use proper feedback drivers)

 

[PinksteR]

Thanks ppl. I'll go with the idea of using the infrared leds instead of the laser pointers.

 

[chemelec]

Here in BC Canada, you can buy the Laser Pens for $1.00 Canadian,
Including the 3 small batteries.

Just buying one new battery wil cost Over that $1.00.

 

[audioguru]

Yeah, the battery companies are ripping us off.
I used to buy cheap battery operated junk just to get the batteries. Usually they were good alkaline but sometimes they were dead carbon-zinc. I avoided the junk that said, "Try it", because their batteries were always dead from kids (and me) playing with them in the store.

Now I buy name-brand batteries when they are on sale and use coupons and multiple bonus extra packs for an even lower price. They are date-stamped so of course I select the newest ones.
I recently got a pack of expensive Energizer Lithium cells free for doing a survey about them.

I never buy the Titanium or e2 "improved" more expensive battery cells because their datasheets show that they perform exactly the same as ordinary Energizer ones. :lol:

 

[williB]

i recently found a "multipurpose flexable ligh" in the dollar store , china made ..
it has three LR44 batteries and a white LED all for 2 bucks..
the LED alone would probably sell for more than that !!
i bought two :lol: :lol:

 

[chemelec]

audioguru, I never buy the Titanium or e2 "improved" more expensive battery cells because their datasheets show that they perform exactly the same as ordinary Energizer ones.

Not sure about the E2 batteries, but I'm Very Impressed with the Titanium one. Except for the Price. But Even than they Out-perform all other batteries in my Camera and do save money.

NiMh batteries are Good, Cheaper in the long run, but lousy for sitting on the shelf as spares.

 

[audioguru]

I'm Very Impressed with the Titanium one......they Out-perform all other batteries in my Camera

Shortly after I pointed out that the Energizer Titanium cell has exactly the same spec's and weight as their cheaper Energizer one, and I made jokes on the www that it is made like a very dry martini (the vermouth [titanium] is in a factory across the street), Energizer stopped selling them. Their expensive new e2 cell is about the same. You don't pay for the battery, instead you pay for their ads.

It is funny that the other razor blade (battery) manufacturer (Duracell) doesn't post detailed spec's for their batteries. They are still trying to figure out how to make a 1.5V Lithium cell since they are (were) always 3V.

Try Energizer's new Lithium AA cells. They do last much longer in a digital camera than alkaline cells. :lol:

 

[tom2000]

Here in BC Canada, you can buy the Laser Pens for $1.00 Canadian,
Including the 3 small batteries.

Just buying one new battery wil cost Over that $1.00.

where the hell are you getting your batteries ????

i get my laser pointers for a buck also, in the dollar store, and then i go to another shelf and buy 10 Batteries for it......FOR also a Dollar !!!

 

[audioguru]

My dollar stores don't sell the batteries.
They are about $3.00 each at drugstores and car-parts stores. Those stores make a pretty good ripoff for a $.10 battery, don't they? :cry: