divindavid said:hey i have another question i know that this circut you guys posted is to make the laser last a long time and i know that theres an easer way with out the LM317 capassaters and resisters. because i saw a video on youtube
does any have the circuit diograhm that goes from the diode to the pot and then the power sourse if so can you please post it
the reson why i am not looking for the hard way to do it is becuase this is my first time builting one and i have two of everything i need (i accidentally ordered two)
soo
D.
If the laser diode had a fixed resistance then yes, you could just use another resistor to limit the current. But a laser diode, like any other semiconductor, changes it's resistance depending on how much current is flowing through it and on the junction temperature.
This is why you need a laser diode driver.
As for the Youtube video, Youtube is for entertainment and nothing more. Anything you see on Youtube is crap. Never ever trust it. (unless you believe that there are 1500 AAs and a unicorn inside every car battery. LOL, I hope you've seen that video or else I'll look like even more an ass.)