How can i connect Laser Diode to Arduino?

Hi everyone, I have a question how can i connect laser diode to arduino please ?

What type of laser diode? In what package? That's about the same as asking "how do I open a computer case?".

Hmm… i dont know the reference of the Laser diode because i recover it from a CD Driver, but it’s like the image below

You probably need a resistor to provide the diode with the correct current. Then by connecting the diode to a pin, and setting that pin high or low, you can control it. Keep in mind that for an Arduino Uno, you should not draw more than 20mA. If the diode takes more than 20mA, you should use a transistor.

You will need to know the diodes forward voltage and current to determine resistor size.

Edit: I just looked it up and found that a 115mW diode needs a 1KOhm resistor, so you shouldn’t go much below that

Circuit to give you an idea on powering it

ah okay, thanks for your comment, i found this schematic on the internet what do you think ?

where can i put the arduino ?

Thats pretty good. You would need a lot of power for that, and definitely need a good transistor and power supply of some sort (USB is probably not enough, if you hook up much else to the Arduino).

Transistors are kind of like relays, functioning as an electrical switch. You would wire one to one end of the circuit, in series with the power supply. Then the trigger wire goes to the Arduino. It might also be possible to use 2 separate power sources if needed.

Hopefully someone with better knowledge might be able to offer a more viable solution

The circuit you posted is called a DDL driver, after the fellow who originally posted it on It is a modified constant current regulator, based upon a linear voltage regulator IC configured as a current regulator. Not real efficient (%power in vs. %power out), but perfectly servicable for the diodes in question, IF, you know the threshold current of your LASER Diode, and, the Maximum Rated current of your diode, and how to set the current limit of the driver to a value somewhere in between, and, of course, what kind of diode you have.

You said you recovered it from a CD driver (what is that?), If you got it out of a CD-ROM reader, it is a useless I.R. Useless, to low power to really do any burning, and hazardous to play with because it is invisible emission. If you got it out of a CD Read/Write Drive, it could be the READ diode (which is a useless I.R.), or the WRITE diode ( a moderate to low power RED diode). If you got it out of a DVR writer, it gould be the same as a CD-ROM drive (except the RED will be a little more powerful). Then there’s BlueRay,

I.R. LDs are mostly 2.2v fwd, case positive
RED, and BLUES, are about 4-5v fwd and case negative.

You need the diode, a mounting with a heatsink, a driver and a power source. A Arduino ain’t gonna cut it as a power source, and the DDL does not have an added Modulation circuit. You COULD use the arduino to drive a power MOSFET or HEXFET as a power switch between the power source and the driver positive feed (pretty expensive switch). You would need to set the driver current limit with a test load, turn off power, disconnect test load, short the driver’s output cap to discharge, THEN connect the diode.
Observe Static Electricity precautions.

Anybody who suggests that you use a resistor as a current limitter is uninformed or a fool. Your diode won’t survive long in that configuration (especially if you try to run it close to max current).

Go to LaserPointerForum, or some other laser forum, and do a lot of reading before you proceed with this project.

Then again, free advice is worth every penny you pay for it. Do your research first, or suffer the consequences. Your choice.