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

IR/green laser diodes' regulated power

Joined
Feb 19, 2008
Messages
17
Points
0
What is the spec for input voltage of the diode itself? I understand that an entire pen assembly probably has some kind of voltage divider circuit at the least, if not some voltage regulation built in.

Just wondering if the end product of the pen is built for best performance with 3.0 volts and that using 2.4 volts is underpowering them. If so itd be great if these manufacturers built 2 models, one spec'ed for 2x 1.5v cells, and another spec'ed for 2 1.2v cells. But I guess that would only be possible if the diodes thenselves work at 2.4 volts or lower.
 





Joined
Feb 26, 2008
Messages
31
Points
0
For the most part, the limiting factor on any light emitting diode is current, not voltage (Excluding static sensitive stuff like blue LEDs)

The "gist" of a laser diode driver does the following...

*Limit absolute maximum current to the diode through a resistor in series with the laser diode.

*Control running current with a transistor/op amp based drive, controlled by the internal photodiode, external one, or both.

*Soft start the diode with a cap across the diode leads. (Nanoseconds, not much. Just enough to reduce peaks, and prevent static damage.)


Thats it. Increasing voltage to the laser driver will have no effect on laser brightness or output, until the driver loses control (transistor saturation/avalanche, thermal run away, complete die failure, etc), then POOF. Dark emitting laser diode.
 




Top