make a laser pointer

[chri$]

Hi everyone,

I'm about to make a laser pointer (red laser 1mW, alimentation min 3Vdc and current <60mA). So, here's my question. Can I just put 2 resistors ( the both are 10 ohm) and potentiometer (100 ohm) ? or I should add components like diodes and voltage regulator ?

 

[betwixt]

You can just use resistors but most laser diodes also have a sensor in them to read the light level. With a simple external circuit you can control the current to ensure the diode says in it's laser mode regardless of battery voltage, as long at there is enough voltage of course!

Brian.

 

[jiripolivka]

Low-cost laser pointers use the simple dropping resistor circuit. Open one and see for yourself. The more complex circuits are not designed for laser pointers but for optical fiber communication systems, need a higher supply voltage than 3 V.

 

[chri$]

Thanks for your replies.

I'll try with what I have.