Problem with my LM317 driver + Test Load

[sinner]

Sorry if this has been mentioned before but after a lot of reading , what i gather is very confusing for me, i just wanted to ask if i am doing it right or not..
Now my question is,
- will it kill the diode, the +0.46V difference (Close Can diode from 16x DVD)
- Is there any problem in the circuit?
- Am i using the multimeter wrong? (i know how to use it , but just in case)
Thanks for your patience
P.S: Sorry for the crappy circuits , i made it just to demonstrate in the images, my soldering iron has not yet arrived and also the aixiz modules are taking me too long, so my learning is yet in test-mode :S

 

[jimdt7]

I am 99% sure that 0.49V wont damage your diode !

 

[sinner]

Now , its getting more complicated, now i tried with another resistor ,
the Voltage is 3.71V @400mA with 3Ohm + Lm317..
It should be 3.71V what do i need to do to drop the Voltage closer to 3.00V while current remains the same !

 

[Cyparagon]

It's quite simple, really - It's a constant current driver. It will supply 320mA no matter the load (within reason)

 

[Ghostchrome]

You just need constant current. The voltage regulator will take care of the rest. Voltage will vary depending on the demand. Remember that your test load is not going to demand the exact same amount of voltage that your diode will due to component tolerances, heat, etc. Your laser diode should be fine as long as your circuit is correct.

edit: Cyparagon beat me to it.

 

[sinner]

Thanks Ghostchrome, the current i needed is perfect, And you have cleared the confusion about the voltage increase too.. so i am very glad, and will post the photos of my first build soon

 

[Ghostchrome]

Right on. Looking forward to your build!