laser pointer

[excaliberx18]

For my electronics class I have to do a sophmore project and have to build something moderately difficult. So I decided to make a laser pointer. I've searched the internet for a while and couldn't find any schemiatics. Can someone help? Also, any pointers would be great.

(first post)

 

[Menticol]

Is like making a computer processor using household materials!

Buy your laser pointer at any store, then select another project

 

[Torben]

Is like making a computer processor using household materials!

Buy your laser pointer at any store, then select another project

Hi Menticol!

Oddly, I was going to say the exact opposite--that this is ridiculously simple, if you can find a suitable laser diode. One 5mW laser diode, three button cells, a resistor, and a little wire. Supposedly the internal resistance of the button cells means a current-limiting resistor is not needed, although I'd probably start out with one myself.

Problem is, I usually get my laser diodes by buying dollar-store laser pointers. For $1 I get a laser diode, three button cells of unknown charge, an SMD resistor, and a microswitch.

Sadly, taking a laser pointer apart just to make a laser pointer seems like a waste of time, unless it's to make a better pointer--which might be desirable since the dollar-store ones are badly built and the original batteries often outlive the actual unit.

If you're talking about building a laser pointer truly from scratch, then yeah--that's more serious stuff indeed. Building a laser at home can be done, but building a laser *diode* at home would probably be a bit extreme.


Torben

 

[Menticol]

Haha yes Torben! I was refering to the last case: As the OP said "making a laser pointer", I imagined him making the neodymium-doped yttrium aluminium crystals in the kitchen

Your idea is great, the included coin cells are total crap (God knows who made them and what materials they used). As a project, he could make the cylinder, the springs and the caps to accomodate two decent AA cells and a switch. At the end of the cylinder, the dollar store diode.

 

[excaliberx18]

Is there anyplace I could get a laser diode at....like maybe Radio Shack. I sort of want my laser diode to be not as cheap as the dollar store ones, and somehow making a laser pointer from a laser pointer doesn't seem as appealing as buying the seperate parts and making it that way. But...how do the dollar tree one's perform? Can they hit an objects from a distance or does the light not go very far. Im looking for a diode that can emit a small but strong and concentrated beam of light that can hit an object from a distance. Would this be determined by the diode or how much current is put in it? By the way thx for all the comments.

 

[blueroomelectronics]

Keep in mind many schools have banned laser pointers, make sure you can bring it to class. Also it can be a danger to others eyesight so be careful.

What sort of course wants you to build a laser pointer?

 

[excaliberx18]

First of all, I don't think any of my teachers are smart enough to see it and I have Electronics class(a.k.a. the class im doing this for),so its perfectly fine for me to bring it out in that class. Ill probably be working on this project in the class anyway seeing as I mite not have the materials i need and my teacher can help me. Also, i'll be careful not to point it in anyone's eye.

 

[gentalusiav]

i use laser pointer for home security system..my problem now are to develop receiver circuit using phototransistor as a detector sensor..anyone can help?