Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Help needed for a simple laser

Adeon

0
Joined
Feb 14, 2014
Messages
1
Points
0
Hi, I`m new to this, and I`ve recently started buildin my own laser, but hit a dead end with something, and hoping that one of you can help me.

I`ve picked a 5.6 mm red laser diode from a dvd burner, and built the circuit using this youtube link:

https://www.youtube.com/watch?v=dsWbqP6z-X4

I`ve bought a laser housing unit:

Carcasa modul laser diode 5.6mm tip TO-18 aluminiu,kit cu lentila acrilica, set complet

but after mounting it it works, but even when a turn the variable resistor to a minimum (max curent) the light is not as powerful and it only shoes a dot at very close range (a distance of 20 cm max), it`s like it`s not focused (I`ve tried focusing it, it doesen`t do much).

I`ve measured the output curent and voltage at the end of the circuit, right were the diode connects to the driver circuit: The voltage is 9 volts constant...and the curent depending were I set the variable resistor is betwen 10mA and 240mA. My question...is the voltage to high ? I don't know exactly what type of diode it is...I only now it's 5.6mm dimensions, closed can...and I think it's TO18 package. Cand someone please help me ?
 





Joined
Jan 7, 2007
Messages
6,309
Points
83
That voltage looks too high for a red diode. Do you have
a heat sink -- I see your pictures but does it have a tight
diode fit? Where did you measure the diode voltage?
Drivers vary on + or - ground and how you meter them.
Also that big capacitor across the LD can be a problem.
Is it soldered together?
HMike
 
Last edited:




Top