650nm 4W C mount

[logsquared]

When I put a 100mm FL lens about 100mm from the diode the beam is about 9mm wide and the spot @ 28M is about 50mm wide. When I put a 50mm lens in about 50 mm from the diode, the beam is about 6mm wide and the far field is about 60mm wide.

That truly is very odd. You would expect a linear reciprocal relationship.

[DTR]

So, it looks as though the raw divergence is vastly different between diodes. At least I know I am not losing my mind.

Is it possible the FAC got knocked out of place or off completely on it either before or after receiving? I have a customer that has bought over 50 units over the last couple months and have not heard about any inconsistency issues with them. Maybe yours was an fluke. If this were the case and it was some kind of defect I would have swapped it out for you. That is the only thing I can think of other than a testing issue but I believe you would be pretty thorough in your measurements.

[planters]

This is what turned me off. If I had 9mm I would have been jumping for joy. These were to be used with the 9.5mm eye magics. I could have knifed 4 of them on the mirrors or 8 with pbs.

Of course you ...could use a PBS as well. Then, well then a SS laser module with Laserscope power smaller than a laptop!

[logsquared]

Is it possible the FAC got knocked out of place or off completely on it either before or after receiving? I have a customer that has bought over 50 units over the last couple months and have not heard about any inconsistency issues with them. Maybe yours was an fluke. If this were the case and it was some kind of defect I would have swapped it out for you. That is the only thing I can think of other than a testing issue but I believe you would be pretty thorough in your measurements.

The beam in the FAC'ed axis was great. I looked at the FAC with a microscope just cause i was curious... It looked fine. Everything focused well and looked great. It made the power it should. If I had thought it was off spec I would have asked for a "trade in". I believe this diode must have been the odd guy out so to speak. Good news really.

Just for information sake.... here is how I measured the SA divergence: I shone the diode at a flat wall 79" away from the emitter. I then measured and recorded the dimensions of the spot on the wall at different currents. I used these dimensions to calculate the full angle of the beam.

Out of curiosity, its been a few months since I looked at these, what is the latest recommended safe drive current?

[DTR]

Probably recommend 4A and suggesting the use of a lasorb. I drive the one I use to 5A the max of my supply all the time and have not seen any degradation or issues yet and if I remember correctly Angelos killed one on purpose at about 7A. A power graph may be good to see where efficiency is the highest.

[badger1666]

Has anyone tried a prism pair after the diode but before collimating lens ?

[absolom7691]

Do I have to be the one to say that this thread is WORTHLESS WITHOUT PICTURES? Actually, knowing Eric, I am sure he will put together a really awesome video.

[LightningStalker]

What is a good place to get a lasorb for my poor little defenseless diode?

[mixedgas]

Call Pangolin, I've had no problem ordering a few pieces of Lasorb from them.
Steve

[LightningStalker]

Okay, thanks. Will do