Homemade Laser Pointer

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Posted in TechnologyLasers

Introduction: Homemade Laser Pointer

About: I love electronics and all about DIY.

Last week i purchased a laser pointer for my little brother, I told him to be careful with it. Two days later, he opened the laser and broke it, he was sad and i decided to make a new one.
I started to look for instructables about laser pointers and there were laser drivers, laser burners, laser spirographs... But no simple pointers from dvd readers laser diodes (i didnt want to buy a new laser on the internet and in my small city i didnt find any).
Then i decided to mix all instuctables i saw to make a easy laser pointer with some recycled materials. (I didn't made it able to burn because it is mainly for my brother)

Enjoy that instructable and make your own laser.
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Step 1: Materials

What i needed to make that laser is:
- A laser diode, I used visible red diode, but you can use the color you want (or the one you have)
-LM 317 voltage regulator
-2x 10ohm 1/2w resistors
-1N4001 or somilar diode
-One 100nF capacitor
-A 100ohm potentiometer
-A push button
-The PCB (step 2)
-A case (step 4)
-A focusing system (steps 5 & 6)

Step 2: The Driver

To make a proper driver for the laser diode, etch the PCB and solder the components as shown in the diagram.

Some people only connects the LD with a resistor in series, but that driver is a better (but more expensive) way to use a laser diode.

The LM371 varies the voltage the LD uses (i cutted the top because it didnt overheat, i think i does not affect the way it works), the two 10ohm resistors in parallel set the maximum voltage and current the Laser Diode will get, the pot allows adjustment of output current, The 1N4001 diode protects the LD from a negative input as battery placed wrong, but LM317 can't deliver neative voltages, so maybe it is not necessary, and the capacitor protects laser diode  from immediate  power supply especially when switching on.

This driver is a mixture of what i have seen arround, so, if something should not go there, please tell me.

Step 3: Plug to Battery

I had an old battery, and when i thought i was going to use a 9v battery as power supply, i decided to use this one as case and plug.
After you open it, if it is new, use the batteries inside, don't throw them!

I soldered the battery plug to the circuit input, making sure it was correctly polarized.

Step 4: The Casing

As i've said, i used the old battery as a case for the driver, i sanded it and i drilled some ventilation holes because i cutted the top of the LM317 regulator.
Maybe you like to give it a paintjob, but i decided to leave the metal polished.

Step 5: Laser Housing

That two steps are a guidance for you, because i used parts that i had on hand, that sure you don't have, you have to improvise, or buy a laser housing with its lens.

Step 6: Focusing System

For the focusing system i used a potentiometer threaded part and its nut and a salvaged lens from the dvd reader.
It is not perfect but it focuses the beam ad it's free!

Step 7: Putting It All Together

I connected the driver to the laser diode and after making sure it works, i insulated the driver with tape, i introduced it into the case and i glued it to prevent pulling it out with cyanocrylate, But epoxi would work better.
The laser housing was hot glued making a diode replacement easier.

Step 8: Done!

The laser pointer war finished and ready to use, my little brother is now happy with it's new pointer and the cats in the street :3.
The laser reaches 150ft if you focus it well and it is about 5$ in materials and made by yourself!

If you liked my instuctable, please, vote me in the Epilog laser, pocket-sized electronics and battery powerwed contests.


If i win the laser cutter, thing that probably will not happen, I'll use it for engraving everithing i can, for cutting gears, cases, 123D kits... It would be totally awsome!

Feel free to ask me anything you didn't understand or propose upgrades.
Bye.

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    105 Comments

    http://www.taringa.net/post/info/18742491/Como-hacer-un-puntero-laser-paso-a-paso.html#comment-1433690

    Bien ahí los taringueros!

    Vamos los taringeros! por fin algo de inteligencia colectiva

    It's ok if they use it, they have icluded the link to the source.

    Thanks. Now I see why I thought it was too simple: you simply drive the diode with no feedback. That's what normally the 3rd pin is for (as you asked). From this pin you can read back the laserpower.
    Think of it like a small solar cell inside the laserdiode which gives you voltage in a function of laserpower.

    Honestly I think you don't need that here since you don't need to compensate the few microwatts dropped in laserpower due to heating and such...

    Hi guys, I got a laser diode from my DVD writter drive.before making the driver circuit I just want to check the laser diode is working or not .so I checked with a multimeter using diode mode.there is no light rays multimeter shows the value 1702 but no beep sound.is that spoiled? Plz help me

    Hi guys, I got a laser diode from my DVD writter drive.before making the circuit I just want to check the laser diode is working or not .so I checked with a multimeter using diode mode.there is no light rays multimeter shows the value 1702 but no beep sound.is that spoiled? Plz help me

    What materials do you need to have to make it run on a 3.7 battery?

    No, it uses a 5mw diode.

    would it burn if i had used a diode from lets say a dvd burner

    Yo,I have a lens used in laser and a really powerful bulb.Will you folks help me in making a laser outta it?

    1 reply

    It would not work because a laser diode does not produce light light a bulb, it concentrates light into a beam which is why they are dangerous and powerful. On the other hand, a bulb will produce light waves in a scatter and not a beam.

    Do I need a potentiometer if I am going to keep it on max current? I want to make this I just don't want to spend an extra $3 for 20 100Ω trimpots (yes i know my schematic will be different) and have an extra 19. Can i substitute it with a jumper wire or make the connection solid?

    According to my understanding of the LM317, the other end of the potentiometer should be connected to ground.

    2 replies

    I'm not using it as a voltage regulator, but as a current source.