Flexmod and 445

[gottaluvlasers]

hey-

any ideas why in only getting ~450mW-550mW out of my flexmod3? I just put together a (what i hoped would be) 1W/445. No matter what i set the Flexmod to i only gett about max. 500mW out of it.

At one point, i potted it up and it got up to ~750-800mW but then backed off and DRASTICALLY diminished power to <100mW.

its just roughy set up now. HEatsinked and clamped to a block of aluminum. so, i dont think its getting too hot. The diode is brand new also with a lasorb on it.

any ideas?

-Marc

[allthatwhichis]

Are you sure you are giving the flexmod enough voltage? Enough blanking voltage?

[swamidog]

if you're using the older N2 version, make sure the low/high solder bridge connection is electrically connected.

hey-

any ideas why in only getting ~450mW-550mW out of my flexmod3? I just put together a (what i hoped would be) 1W/445. No matter what i set the Flexmod to i only gett about max. 500mW out of it.

At one point, i potted it up and it got up to ~750-800mW but then backed off and DRASTICALLY diminished power to <100mW.

its just roughy set up now. HEatsinked and clamped to a block of aluminum. so, i dont think its getting too hot. The diode is brand new also with a lasorb on it.

any ideas?

-Marc

[gottaluvlasers]

@aaron-

yeah, its on a bench top supply with a set 5V in. if i lower the input mod. signal to about 4.8 volts the power actually goes up but then drifts back down.

@ swami -

How do i know if its an "N2?" I just got them about 1 month ago.

-Marc

[swamidog]

if it looks like this, it's the N2:

http://hacylon.case.edu/ebay/FlexMod/driver.jpg

@aaron-

yeah, its on a bench top supply with a set 5V in. if i lower the input mod. signal to about 4.8 volts the power actually goes up but then drifts back down.

@ swami -

How do i know if its an "N2?" I just got them about 1 month ago.

-Marc

[drlava]

Hi Marc, what current are you setting the Bias to, and what current are you setting the gain to? The FlexMod is a current driver device, it doesn't produce light itself so the best way to isolate the troubleshooting to your driver setup is to speak in terms of current. A multimeter in amps mode in series with a dummy load is a good setting tool.

[300EVIL]

It's most likely a FlexMod3 then. Turn down the gain pot about ten turns CCW then try applying 8-12V. 5V is just too low.

[gottaluvlasers]

@dr lava-

1) i just ordered a few of these from you. they in stock?

2) The driver that i have now is one of your new ones and it arrived to me from someone else with the wires already soldered on, so i did not set the bias or anytihng. The guy who sent it to me said he already set it. At "0V" the laser is completely off though. i know most people have a lsight glow.

should i unsolder the wires already on it and set this from scratch?

3) What is the average current setting for about 800mW of output?

4) for the bias setting, am i looking for a current reading on this? or am i just adjuting the bias to *JUST* barely keep the diode glowing at a "0V" input mod signal?

@300evil-

I amusing a 7V input actually. I may try a 12V input just for shits and giggles though. i think i should set this from scratch.

if i unsolder all the existing wires that already came on this, what type of load should i have on the output to set the current? do i just attach the meter directly to the output of the driver and no dummy load needed?

Sorry...these prob seem like stupid questions, but i am in a stupid rush and need to get this done ASAP.

-Marc

[300EVIL]

@300evil-

I amusing a 7V input actually. I may try a 12V input just for shits and giggles though. i think i should set this from scratch.

if i unsolder all the existing wires that already came on this, what type of load should i have on the output to set the current? do i just attach the meter directly to the output of the driver and no dummy load needed?

Sorry...these prob seem like stupid questions, but i am in a stupid rush and need to get this done ASAP.

-Marc

Hmmm, 7V should be good enough. I personally use 12V on the FlexMod 3's when powering 445 diodes though. Your PS should be able to make at least 1.5A in order to power the FM3 and diode.

I personally do not use a dummy load.... For 445nm diodes, I put my Fluke meter directly across the output without diode or dummy load installed and adjust to 300mA at 5V at the modulation input. From there, I connect the diode and adjust my output with a power meter.

[drlava]

@dr lava-

1) i just ordered a few of these from you. they in stock?

Thank you! They are in stock and I'll be processing it tomorrow.

2) The driver that i have now is one of your new ones and it arrived to me from someone else with the wires already soldered on, so i did not set the bias or anytihng. The guy who sent it to me said he already set it. At "0V" the laser is completely off though. i know most people have a lsight glow.

should i unsolder the wires already on it and set this from scratch?

If he didn't tell you what he set it at (and it sounds like you have adjusted it without knowing what current you adjusted it to) yes I'd start from scratch setting up the bias and gain. Here are the setup instructions:
http://hacylon.case.edu/laser/FlexMo...dP3_Manual.pdf

3) What is the average current setting for about 800mW of output?

I follow the formula I = 0.2 + W/1.3 when you are using a good short lens so for 800mW target 815mA. Diode efficiency varies.

4) for the bias setting, am i looking for a current reading on this? or am i just adjuting the bias to *JUST* barely keep the diode glowing at a "0V" input mod signal?

you'll want to keep the diode just glowing with a lasorb attached via the bias current setting. 7V input is plenty. No dummy load is really needed unless you are wanting to test for dropout at low power supply voltages.